Skip to main content

Full text of "Philosophical transactions of the Royal Society of London"

See other formats 


PHILOSOPHICAL 


TRANSACTIONS 

OF  THE 

ROYAL  SOCIETY 

OF 

LONDON. 


FOR  THE  YEAR  MDCCCXLIX. 


PART  L 


LONDON: 

PRINTED  BY  RICHARD  AND  JOHN  E.  TAYLOR,  RED  LION  COURT,  FLEET  STREET. 


MDCCCXLIX. 


ADVERTISEMENT. 


The  Committee  appointed  by  the  Royal  Society  to  direct  the  publication  of  the 
Philosophical  Transactions take  this  opportunity  to  acquaint  the  Public,  that  it  fully 
appears,  as  well  from  the  Council-books  and  Journals  of  the  Society,  as  from  repeated 
declarations  which  have  been  made  in  several  former  Transactions,  that  the  printing 
of  them  was  always,  from  time  to  time,  the  single  act  of  the  respective  Secretaries 
till  the  Forty-seventh  Volume ; the  Society,  as  a Body,  never  interesting  themselves 
any  further  in  their  publication,  than  by  occasionally  recommending  the  revival  of 
them  to  some  of  their  Secretaries,  when,  from  the  particular  circumstances  of  their 
alfairs,  the  Transactions  had  happened  for  any  length  of  time  to  be  intermitted.  And 
this  seems  piincipally  to  have  been  done  with  a view  to  satisfy  the  Public,  that  their 
usual  meetings  were  then  continued,  for  the  improvement  of  knowledge,  and  benefit 
of  mankind,  the  great  ends  of  their  fii’st  institution  by  the  Royal  Charters,  and  which 
they  have  ever  since  steadily  pursued. 

But  the  Society  being  of  late  years  greatly  enlarged,  and  their  communications 
more  numerous,  it  was  thought  advisable  that  a Committee  of  their  members  should 
be  appointed,  to  reconsider  the  papers  read  before  them,  and  select  out  of  them  such 
as  they  should  judge  most  proper  for  publication  in  the  future  Transactions ; which 
was  accordingly  done  upon  the  26th  of  March  1752.  And  the  grounds  of  their 
choice  are,  and  will  continue  to  be,  the  importance  and  singularity  of  the  subjects,  or 
the  advantageous  manner  of  treating  them ; without  pretending  to  answer  for  the 
certainty  of  the  facts,  or  propriety  of  the  reasonings,  contained  in  the  several  papers 
so  published,  which  must  still  rest  on  the  credit  or  judgement  of  their  respective 
authors. 

It  is  likewise  necessary  on  this  occasion  to  remark,  that  it  is  an  established  rule  of 
the  Society,  to  which  they  will  always  adhere,  never  to  give  their  opinion,  as  a Body, 

a 2 


[ iv  ] 

upon  any  subject,  either  of  Nature  or  Art,  that  comes  before  them.  And  therefore 
the  thanks,  which  are  frequently  proposed  from  the  Chair,  to  be  given  to  the  authors 
of  such  papers  as  are  read  at  their  accustomed  meetings,  or  to  the  persons  through 
whose  hands  they  received  them,  are  to  be  considered  in  no  other  light  than  as  a 
matter  of  civility,  in  return  for  the  respect  shown  to  the  Society  by  those  communi- 
cations. The  like  also  is  to  be  said  with  regard  to  the  several  projects,  inventions, 
and  curiosities  of  various  kinds,  which  are  often  exhibited  to  the  Society  ; the  authors 
whereof,  or  those  who  exhibit  them,  frequently  take  the  liberty  to  report  and  even  to 
certify  in  the  public  newspapers,  that  they  have  met  with  the  highest  applause  and 
approbation.  And  therefore  it  is  hoped  that  no  regard  will  hereafter  be  paid  to  such 
reports  and  public  notices ; which  in  some  instances  have  been  too  lightly  credited, 
to  the  dishonour  of  the  Society. 


The  Meteorological  Journal  hitherto  kept  by  the  Assistant  Secretary  at  the  Apart- 
ments of  the  Royal  Society,  by  order  of  the  President  and  Council,  and  published  in 
the  Pliilosophical  Transactions,  has  been  discontinued.  The  Government,  on  the 
recommendation  of  the  President  and  Council,  has  established  at  the  Royal  Obser- 
vatory at  Greenwich,  under  the  superintendence  of  the  Astronomer  Royal,  a Magnet- 
ical  and  Meteorological  Observatory,  where  observations  are  made  on  an  extended 
scale,  which  are  regularly  published.  These,  which  correspond  with  the  grand 
scheme  of  observations  now  carrying  out  in  different  parts  of  the  globe,  supersede 
the  necessity  of  a continuance  of  the  observations  made  at  the  Apartments  of  the 
Royal  Society,  which  could  not  be  rendered  so  perfect  as  was  desirable,  on  account 
of  the  imperfections  of  the  locality  and  the  multiplied  duties  of  the  observer. 


A List  of  Public  Institutions  and  Individuals,  entitled  to  receive  a copy  of  the 
Philosophical  Transactions  of  each  year,  on  making  application  for  the  same 
directly  or  through  their  respective  agents,  within  five  years  of  the  date  of  pub- 
lication. 


In  the  British  Dominions. 

The  Queen’s  Library. 

The  Admiralty  Library. 

The  Ashmolean  Society,  Oxford. 

The  RadclifFe  Library,  Oxford. 

The  Royal  Geographical  Society. 

The  United  Service  Museum. 

The  Royal  College  of  Physicians. 

The  Society  of  Antiquaries. 

The  Linnean  Society. 

The  Royal  Institution  of  Great  Britain. 

The  Society  for  the  Encouragement  of  Arts. 

The  Geological  Society. 

The  Geological  Survey  of  Great  Britain. 

The  Horticultural  Society. 

The  Royal  Astronomical  Society. 

The  Royal  Asiatic  Society. 

The  Royal  Society  of  Literature. 

The  Medical  and  Chirurgical  Society. 

The  London  Institution. 

The  Entomological  Society  of  London. 

The  Zoological  Society  of  London. 

The  Institute  of  British  Architects. 

The  Institution  of  Civil  Engineers. 

The  Cambridge  University  Philosophical  Society. 
The  Literary  and  Philosophical  Society,  Man- 
chester. 

The  Royal  Society  of  Edinburgh. 

The  Royal  Irish  Academy. 

The  Royal  Dublin  Society. 

The  Royal  Institution,  Swansea. 

The  Asiatic  Society  at  Calcutta. 

The  Royal  Artillery  Library  at  Woolwich. 

The  Royal  Observatory  at  Greenwich. 

The  Observatory  at  Dublin. 

The  Observatory  at  Armagh. 

The  Library  and  Museum,  Barbadoes. 

The  Observatory  at  the  Cape  of  Good  Hope. 

The  Observatory  at  Madras. 

The  Observatory  at  Paramatta. 

The  Observatory  at  Edinburgh. 

Denmark. 

The  Royal  Society  of  Sciences  at  Copenhagen. 
The  Royal  Observatory  at  Altona. 

France. 

The  Royal  Academy  of  Sciences  at  Paris. 

The  Royal  Academy  of  Sciences  at  Toulouse. 
The  Ecole  des  Mines  at  Paris. 


The  Geographical  Society  at  Paris. 

The  Entomological  Society  of  France. 

The  Depot  de  la  Marine,  Paris. 

The  Geological  Society  of  France. 

The  Jardin  des  Plantes,  Paris. 

Germany. 

The  University  at  Gottingen. 

The  Caesarean  Academy  of  Naturalists  at  Bonn. 
The  Observatory  at  Mannheim. 

The  Royal  Academy  of  Sciences  at  Munich. 
Italy. 

The  Institute  of  Sciences  at  Naples. 

The  Institute  of  Sciences,  Letters  and  Arts,  at 
Milan. 

The  Italian  Society  of  Sciences  at  Modena. 

The  Royal  Academy  of  Sciences  at  Turin. 

Switzerland. 

The  Societe  de  Phys.  et  d’Hist.  Nat.  at  Geneva. 
Belgium. 

The  Royal  Academy  of  Sciences  at  Brussels. 
Netherlands. 

The  Royal  Institute  of  Amsterdam. 

The  Batavian  Society  of  Experimental  Philosophy 
at  Rotterdam. 

Spain. 

The  Royal  Observatory  at  Cadiz. 

Portugal. 

The  Royal  Academy  of  Sciences  at  Lisbon. 
Prussia. 

The  Royal  Academy  of  Sciences  at  Berlin. 

The  Society  of  Experimental  Philosophy,  Berlin. 

Russia. 

The  Imperial  Academy  of  Sciences  at  St.  Peters- 
burgh. 

The  Imperial  Observatory  at  Pulkowa. 

Sweden  and  Norway. 

The  Royal  Academy  of  Sciences  at  Stockholm. 
The  Royal  Society  of  Sciences  at  Drontheim. 

United  States. 

The  American  Philosophical  Society  at  Phila- 
delphia. 

The  American  Academy  of  Sciences  at  Boston. 
The  Library  of  Harvard  College. 

The  Observatory  at  Washington. 

The  ffty  Foreign  Members  of  the  Royal  Society. 


A List  of  Public  Institutions  and  Individuals,  entitled  to  receive  a copy  of  the 
Astronomical  Observations  made  at  the  Royal  Observatory  at  Greenwich,  on 
making  application  for  the  same  directly  or  through  their  respective  agents,  within 
two  years  of  the  date  of  publication. 


In  the  British  Dominions. 

The  Queen’s  Library. 

The  Board  of  Ordnance. 

The  Royal  Society. 

The  Savilian  Library,  Oxford. 

The  Library  of  Trinity  College,  Cambridge. 

The  University  of  Aberdeen. 

The  University  of  St.  Andrews. 

The  University  of  Dublin. 

The  University  of  Edinburgh. 

The  University  of  Glasgow. 

The  Observatory  at  Oxford. 

The  Observatory  at  Cambridge. 

The  Observatory  at  Dublin. 

The  Observatory  at  Armagh. 

The  Observatory  at  the  Cape  of  Good  Hope. 

The  Observatory  at  Paramatta. 

The  Observatory  at  Madras. 

The  Royal  Institution  of  Great  Britain. 

The  Royal  Society,  Edinburgh. 

The  Observatory,  Trevandrum,  East  Indies. 

The  Astronomical  Institution,  Edinburgh. 

The  President  of  the  Royal  Society. 

The  Lowndes  Professor  of  Astronomy,  Cambridge. 
The  Plumian  Professor  of  Astronomy,  Cambridge. 
L.  Holland,  Esq.,  London. 

Sir  John  William  Lubbock,  Bart. 

Captain  W.  H.  Smyth,  R.N.,  Chelsea. 

Sir  James  South,  Observatory,  Kensington. 


In  Foreign  Countries. 

The  Royal  Academy  of  Sciences  at  Berlin. 

The  Royal  Academy  of  Sciences  at  Paris. 

The  Imperial  Academy  ofSciences  at  St.  Peters- 
burgh. 

The  Royal  Academy  of  Sciences  at  Stockholm. 
The  Royal  Society  of  Sciences  at  Upsal. 

The  Board  of  Longitude  of  France. 

The  University  of  Gottingen. 

The  University  of  Leyden. 

The  Academy  of  Bologna. 

The  American  Academy  ofSciences  at  Boston. 
The  American  Philosophical  Society  at  Phila 
delphia. 

The  Observatory  at  Altona. 

The  Observatory  at  Berlin. 

The  Observatory  at  Breslau. 

The  Observatory  at  Brussels. 

The  Observatory  at  Cadiz. 

The  Observatory  at  Coimbra. 

The  Observatory  at  Copenhagen. 

The  Observatory  at  Dorpat. 

The  Observatory  at  Helsingfors. 

The  Observatory  at  Konigsberg. 

The  Observatory  at  Mannheim. 

The  Observatory  at  Marseilles. 

The  Observatory  at  Milan. 

The  Observatory  at  Munich. 

The  Observatory  at  Palermo. 

The  Observatory  at  Paris. 

The  Observatory  at  Seeberg. 

The  Observatory  at  Vienna. 

The  Observatory  at  Tubingen. 

The  Observatory  at  Turin. 

The  Observatory  at  Wilna. 

The  Depot  de  la  Marine,  Paris. 

The  Bowdoin  College,  United  States. 

The  Library  of  Harvard  College. 

The  Waterville  College,  United  States. 


List  of  Observatories,  Institutions  and  Individuals,  entitled  to  receive  a Copy  of  tiie 
Magnetical  and  Meteorological  Observations  made  at  the  Royal  Observatory,  Green- 
wich. 


Observatories. 

Altona 

Armagh 

. Rev.  Dr.  Robinson. 

Berlin 

Bombay 

. Dr.  Buist. 

Bamaoul 

. M.  Prang,  1st. 

Breslau 

. Prof.  Boguslawski. 

Brussels 

Cadiz 

Cairo 

Cambridge 

. Prof.  Challis. 

Cambridge,  United  States 

. Prof.  Lovering. 

Cape  of  Good  Hope  . . 

. T.  Maclear,  Esq. 

Catherineburgh  .... 

. M.  RoehkofF. 

Christiania 

Cincinnati 

. Dr.  Locke. 

Copenhagen  

Dublin 

. Sir  W.  R.  Hamilton. 

Gotha 

Hammerfest 

Heidelberg 

Helsingfors 

Hobarton 

. Lieut.  Kay,  R.N. 

Kasan 

Kew 

Kdnigsberg 

Kremsmiinster  .... 

. Prof.  Koller. 

Leipsic 

. Prof.  Weber. 

Madras 

Mannheim 

Marburg 

. Prof.  Gerling. 

Milan 

Munich 

. Dr.  Lamont. 

Nertchinsk 

. M.  Prang,  2nd. 

NikolaiefF 

. Dr.  Knorre. 

Oxford 

Paris 

Pekin 

Prague  

. M.  Kreil. 

Pulkowa 

St.  Helena 

St.  Petersburgh  . . . . 

. M.  KuplFer. 

Seeberg  

Singapore  

Sitka 

IvanofF. 

Stockholm Prof.  Selander. 

Teflis M.  Philadelphine. 

Toronto Captain  Lefroy,  R.A. 

Trevandrum J.  Caldecott,  Esq. 

Tubingen 

Upsal Prof.  Svanberg. 

Vienna C.  L.  von  Littrow. 

Warsaw Col.  G.  Du  Plat  (British 

Consul). 

Washington Lt.  Maury,  U.S.  Navy. 

Wilna 


Institutions. 


Aberdeen  

Berlin 

Bologna 

Bombay 

Bonn 

Boston 

Bowdoin  College  .... 
Bowditch  Library  .... 

Cambridge 

Cherkow 

Dorpat 

Dublin 

Edinburgh 

Edinburgh 

Edinburgh 

Glasgow 

Gottingen 

Harvard,  U.S 

Kiew 

Leyden 

House  of  Lords,  Library  . . 

House  of  Commons,  Library . 
London  


Moscow  . 
Oxford 
Paris  . . 

Paris  . . 

Paris  . . 

Philadelphia 


University. 

Academy  of  Sciences. 
Academy. 

Geographical  Society. 
University. 

Academy  of  Sciences. 
United  States. 

United  States. 

Trinity  College  Library. 
University. 

University. 

University. 

Observatory. 

Royal  Society. 
University. 

University. 

University. 

College. 

University. 

University. 

London. 

>»  >f 

King’s  College. 

Royal  Institution. 

Royal  Society. 
University. 

University. 

Savilian  Library. 
Aeademy  of  Sciences. 
Board  of  Longitude. 
Depot  de  la  Marine. 
Philosophical  Society. 


[ viii  ] 


Queen’s  Library 

London. 

Royal  Cornwall  Polytechnic 

Society 

Falmouth. 

St.  Andrew’s 

University. 

St.  Bernard 

Convent. 

St.  Petersburgh 

Academy  of  Sciences. 

St.  Petersburgh 

Geographical  Society 

Stockholm 

Academy  of  Sciences. 

Upsal 

Society  of  Sciences. 

Waterville,  U.S 

College  Library. 

Individuals. 

Bache,  Dr.  A.  D,  . . . . 

Washington. 

Barlow,  P.  W.,  Esq.  . . 

Woolwich. 

Birt,  W.  H.,  Esq 

London. 

Christie,  S.  H.,  Esq.  . . . 

Woolwich. 

Colebrooke,  Sir  W.  . . . 

Guiana. 

DemidofF,  Prince  Anatole  de 

Florence. 

Dove,  Prof. 

Berlin. 

Erman,  Dr.  Adolph  . . . 

Berlin. 

Fox,  R.  W.,  Esq 

Falmouth. 

Gauss,  Prof 

Gottingen. 

Gilliss,  Lt.  J.  M.,  U.S.  Navy 

Washington. 

Harris,  Sir  W.  Snow  . . . 

Plymouth. 

HoUand,  L.,  Esq 

London. 

Howard,  Luke,  Esq.  . . . 

Tottenham. 

Humboldt,  Baron  von  . 

Kaemtz,  M 

KupfFer,  A.  T.  . . . 

Lawson,  Henry  G.,  Esq. 
Lloyd,  Rev.  Dr.  . . . 

Loomis,  Prof.  . . . 

Lowndes  Prof,  of  Astronomy 
Lubbock,  Sir  John  W.,  Bart. 
Liitke,  Vice-Admiral  . . . 

Melvill,  J.  C.,  Esq.  . . . 

MentchikofF,  Prince  . . . 

Phillips,  John,  Esq.  . . . 

Plumian  Prof,  of  Astronomy 
President  of  the  Royal  Society 

Quetelet,  A 

Redfield,  W.  C.,  Esq.  . . . 

Reid,  Lieutenant- Colonel 
Riddell,  Capt.,  R.A.  . . . 
Roget,  P.  M.,  M.D.  . . . 
Sabine,  Lieut. -Col.,  R.A.  . . 

Senftenberg,  Baron  von  . . 

Smyth,  W.  H.,  Captain  R.N. 
South,  Sir  James  .... 
Wartmann,  Prof.  Elie  . . . 

Wrangell,  Vice-Admiral  . . 

Youngbusband,  Capt.,  R.A.  . 


Berlin. 

Halle. 

St.  Petersburgh. 
Bath. 

Dublin. 

Princeton,  N.I. 

Cambridge. 

London. 

St.  Petersburgh. 
East  India  House. 
St.  Petersburgh. 
York. 

Cambridge. 

London. 

Brussels. 

New  York. 

London. 

Edinburgh. 

London. 

Woolwich. 

Prague. 

London. 

Lausanne. 

St.  Petersburgh. 
Woolwich. 


Adjudication  of  the  Medals  of  the  Royal  Society  for  the  year  1849  by 

the  President  and  Council. 


The  Copley  Medal  to  Sir  Roderick  Impey  Murchison,  F.R.S.,  “for  the  eminent 
services  he  has  rendered  to  geological  science  during  many  years  of  active  observa- 
tion in  several  parts  of  Europe ; and  especially  for  the  establishment  of  that  classifi- 
cation of  the  older  palseozoic  deposits,  designated  the  Silurian  System,  as  set  forth  in 
the  two  works  entitled  ‘The  Silurian  System  founded  on  Geological  researches  in 
England,’  and  ‘ The  Geology  of  Russia  in  Europe,  and  the  Ural  Mountains.’” 

The  Royal  Medal  in  the  department  of  Physics,  to  Lieut.-Col.  Edward  Sabine, 
Foreign  Secretary  R.S.,  for  his  “ Contributions  to  Terrestrial  Magnetism,”  published 
in  the  Philosophical  Transactions  for  1846,  Parts  VII.  and  VIII.,  and  his  Memoir 
“On  the  Diurnal  Variation  of  the  Magnetic  Declination  at  St.  Helena,”  Part  I., 
published  in  the  Philosophical  Transactions  for  1847. 

The  Royal  Medal  in  the  department  of  Geology,  to  Gideon  Algernon  Mantell, 
Esq.,  LL.D.,  F.R.S.,  for  his  paper  “ On  the  Iguanodon,”  published  in  the  Philoso- 
phical Transactions  for  1848,  being  a continuation  of  a series  of  papers  by  him  on 
the  same  fossil  animal,  by  which  he  has  rendered  eminent  services  to  geology. 


The  Bakerian  Lecture  for  1849  was  delivered  by  Michael  Faraday,  Esq.,  F.R.S., 
and  entitled  “ Experimental  Researches  in  Electricity. — Twenty-second  Series.  On 
the  crystalline  polarity  of  bismuth  and  other  bodies,  and  on  its  relation  to  the  mag- 
netic form  of  force.” 


V 


CONTENTS, 


I.  The  Bakerian  Lecture. — Experimental  Researches  in  Electricity. — Twenty-second 

Series.  By  Michael  Faraday,  Esq.,  D.C.L.,  F.R.S.,  Fullerian  Prof.  Chem. 
Royal  Institution,  Foreign  Associate  of  the  Acad.  Sciences,  Paris,  Ord.  Boruss. 
Pour  le  Mdrite,  Eq.,  Memh.  Royal  and  Imp.  Acadd.  of  Sciences,  Petershurgh, 
Florence,  Copenhagen,  Berlin,  Gottingen,  Modena,  Stockholm,  Munich, Bruxelles, 
Henna,  Bologna,  &;c.  8^c . . page  1 

II.  Experimental  Researches  in  Electricity. — Twenty-second  Series  {continued).  By 

Michael  Faraday,  Esq.,  D.C.L.,  F.R.S.,  Fullerian  Prof.  Chem.  Royal  Insti- 
tution, Foreign  Associate  of  the  Acad.  Sciences,  Paris,  Ord.  Boruss.  Pour  le 
Mdrite,  Eq.,  Memh.  Pwyal  and  Imp.  Acadd.  of  Sciences,  Petershurgh,  Florence, 
Copenhagen,  BerUn,G6ttingen,  Modena,  Stockholm,  Munich,  Bruxelles,  Vienna, 
Bologna,  8fc.  8fc 19 

III.  On  the  Ganglia  and  Nerves  of  the  Heart.  By  Robert  Lee,  M.D.,  F.R.S.,  Fellow 

of  the  Royal  College  of  Physicians,  London 43 

IV.  Postscript  to  a Paper  ‘‘  On  the  Ganglia  and  Nerves  of  the  Heart."  By  Robert 

Lee,  M.D.,  F.R.S 47 

V.  On  the  Effect  of  surrounding  Media  on  Voltaic  Ignition.  By  W.  R.  Grove,  Esq., 

M.A.,  V.P.R.S 49 

VI.  On  the  Spontaneous  Electrical  Currents  observed  in  the  Wires  of  the  Electric 

Telegraph.  By  W.  H.  Barlow,  Esq.,  M.  Inst.  C.E.  Communicated  hy  Peter 
Barlow,  Esq.,  F.R.S. 61 

VII.  On  the  Meteorology  of  the  Lake  District  of  Cumberland  and  Westmorelaiid ; 

including  the  results  of  Experiments  on  the  fall  of  Rain  at  various  heights  above 
the  EartJis  surface,  up  3 166  feet  above  the  mean  sea  level.  5?/  John  Fletcher 
Miller,  £’,55'.  Communicated  hy  Lieut.-Col.  SA.Bm'K,  For.  Sec.  R.S.  . . 73 

VIII.  An  Investigation  on  the  Chemical  Nature  of  Wax.  By  Benjamin  Collins 

Brodie,  Esq.  Communicated  hy  Sir  Benjamin  C,  Brodie,  Bart.,  F.R.S.  8^c.  91 

IX.  On  the  Structure  and  Development  of  the  Liver.  By  C.  Handfield  Jones,  M.D. 

Communicated  by  Sir  Benjamin  Collins  Brodie,  Bart.,  F.R.S.  . . . 109 

X.  Minute  Structure  of  the  Papillae  and  Nerves  of  the  Tongue  of  the  Frog  and  Toad. 

By  Augustus  Waller,  M.D.  Communicated  by  Richard  Owen,  Esq.,  F.R.S., 
Sfc 139 

XL  On  the  Development  and  Homologies  of  the  Carapace  and  Plastron  of  the  Chelo- 
nian  Reptiles.  By  Professor  Owen,  F.R.S.  <^c 151 


CONTENTS 


XII.  Contributions  to  Terrestrial  Magnetism. — No.  IX.  By  Lieut. -Colon el  Edward 

Sabine,  R.A.,  For.  Sec.  R.S page  173 

XIII.  Contributions  to  the  Chemistry  of  the  Urine. — Paper  III.  Part  I.  On  the  Va- 

riations of  the  Acidity  of  the  Urine  in  the  state  of  Health.  Part  II.  On  the 
simultaneous  Variations  of  the  amount  of  Uric  Acid,  and  the  Acidity  of  the 
Urine  in  the  state  of  Health.  Part  III.  On  the  Fariations  of  the  Sulphates  in 
the  state  of  Health,  and  on  the  infuence  of  Sulphuric  Acid,  Sulphur  and  Sul- 
phates, on  the  amount  of  Sulphates  in  the  Urine.  By  Henry  Bence  Jones, 
M.D.,  M.A.  Cantab. F.R.S.,  Physician  to  St.  George's  Hospital  . . . 235 

XIV.  Appendix  to  a paper  on  the  Variations  of  the  Acidity  of  the  Urine  in  the  state 

of  Health.  By  Henry  Bence  Jones,  M.D.,  31. A.  Cantab.,  F.R.S.,  Physician 
to  St.  George's  Hospital 261 

XV.  Additional  Observations  on  the  Osteology  of  the  Iguanodon  and  Hylceosaurus. 

By  Gideon  Algernon  Mantell,  Esq.,  LL.D.,  F.R.S.,  F.L.S.,  Vice-President 
of  the  Geological  Society,  8§c 271 

XVI.  On  the  Reduction  of  the  Thermometrical  Observations  made  at  the  Apartments  of 

the  Royal  Society,  from  the  years  1774  to  1781,  and  from  the  years  1787  to  1843. 
By  James  Glaisher,  Esq.,  F.R.S.,  of  the  Royal  Observatory,  Greenwich.  Com- 
municated by  John  Lee,  Esq.,  LL.D.,  F.R.S.  ^c 307 

XVII.  On  the  Meteorology  of  the  Lake  District  of  Cumberland  and  Westmoreland ; 

including  the  results  of  Experiments  on  the  full  of  Rain  at  various  heights,  up  to 
3166  feet  above  the  sea  level.  By  John  Fletcher  Miller,  Esq.,  F.R.A.S. 
Communicated  by  Lieut. -Col.  Sabine,  For.  Sec.  R.S 319 

XVIII.  Description  of  an  Infusory  Animalcule  allied  to  the  Genus  Notommata  of 
Ehrenberg,  hitherto  undescribed.  By  John  Dalrymple,  F.R.C.S.  Commu- 
nicated by  Thomas  Bell,  Sec.  R.S 331 

XIX.  On  the  Motion  of  Gases. — Part  II.  By  Thomas  Graham,  Esq.,  F.R.S. , F.C.S., 
Professorof  Chemistry  in  University  College,  London  ; Hon.  Fellow  of  the  Royal 
Society  of  Edinburgh  ; Corresponding  Member  of  the  Institute  of  France,  of  the 
Royal  Academies  of  Sciences  of  Berlin  and  Munich,  of  the  National  Institute  of 
Washington,  8^c 349 


[ viii  ] 

XX.  Examination  of  the  proximate  Principles  of  some  of  the  Lichens. — Part  II.  Bp 

John  Stenhouse,  F.R.S 393 

XXI.  On  the  Structure  of  the  Dental  Tissues  of  Marsupial  Animals,  and  more  espe- 

cially of  the  Enamel.  By  John  Tomes,  Surgeon-Dentist  to  the  Middlesex 
Hospital.  Communicated  by  R.  E.  Grant,  M.D.,  F.R.S.,  Professor  of  Com- 
parative Anatomy  and  Zoology  at  University  College 403 

XXII.  On  the  Anatomy  and  the  Affinities  of  the  Family  of  the  Medusae.  By  Thomas 

Henry  Huxley,  Esq.,  Assistant -Surgeon  of  H.M.S.  Rattlesnake,  now  engaged 
in  a Surveying  Voyage  conducted  by  Capt.  Stanley  on  the  Coasts  of  Australia 
and  New  Guinea.  Communicated  by  the  Bishop  of  Norwich,  F.R.S.  . 413 

XXIII.  On  the  Microscopic  Structure  of  the  Scales  and  Dermal  Teeth  of  some  Ganoid 
and  Placoid  Fish.  By  W.  C.  Williamson,  Esq.  Communicated  by  Dr.  Lan- 
kester,  F.R.S 435 

XXIV.  On  theNitroprussides,  a New  Class  of  Salts.  By  Dr.  Lyon  Playfair,  F.  R.S.  477 

Index 519 

Appendix. 

L J ] 


Presents 


PHILOSOPHICAL  TRANSACTIONS. 


I.  The  Bakerian  Lecture. — Experimental  Researches  in  Electricity. — Twenty-second 
Series.  By  Michael  Faraday,  Esq.,D. C.L., F.R.S., Fullerian  Prof.  Chem. Royal 
Institution,  Foreign  Associate  of  the  Acad.  Sciences,  Paris,  Ord.  Boruss.  Pour  le 
M6rite,  Fq.,  Memh.  Royal  and  Imp.  Acadd.  of  Sciences,  Petershurgh,  Florence, 
Copenhagen,  Berlin,  Gottingen,  Modena,  Stoehholni,  Munich,  Bruxelles,  Vienna, 
Bologna,  8)C.  ^c. 

Received  October  4, — Read  December  7,  1848. 

28.  On  the  cry^aUine  polarity  of  bismuth  and  other  bodies,  and  on  its  relation  to  the 

magnetic  foirn  of  force. 

^ i.  Crystalline  polarity  of  bismuth.  ^ li.  Crystalline  polarity  of  antimony. 

V ^ iii.  Crystalline  polarity  of  arsenic. 

2454.  Many  results  obtained  by  subjecting  bismuth  to  the  action  of  the  magnet 
have  at  various  times  embarrassed  me,  and  I have  eitiier  been  contented  with  an  im- 
perfect explanation,  or  have  left  them  for  a future  examination : that  examination  I 
have  now  taken  up,  and  it  has  led  to  the  discovery  of  the  following  results.  I 
cannot,  however,  better  enter  upon  the  subject  than  by  a brief  description  of  the  ano- 
malies which  occurred,  and  which  may  be  obtained  at  pleasure. 

2455.  If  a small  open  glass  tube  have  a bulb  formed  in  its  middle  part  and  some 
clean  good  bismuth  be  placed  in  the  bulb  and  melted  by  a spirit-lamp,  it  is  easy 
afterward,  by  turning  the  metal  into  the  tubular  part  of  the  arrangement,  to  cast  it 
into  long  cylinders : these  are  very  clean,  and  when  broken  are  seen  to  be  crystal- 
lized, usually  giving  cleavage  planes,  which  run  across  the  metal.  I prepare  them 
from  0'05  to  OT  of  an  inch  in  diameter,  and,  if  the  glass  be  thin,  usually  break  both 
it  and  the  bismuth  together,  and  then  keep  the  little  cylinders  in  their  vitreous  cases. 

2456.  Taking  some  of  these  cylinders  at  random  and  suspending  them  horizontally 
between  the  poles  of  the  electro-magnet  (2247.),  they  presented  the  following  phe- 


MDCCCXLIX. 


B 


2 DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

nomena.  The  first  pointed  axially ; the  second,  equatorially ; the  third,  equatorial 
in  one  position,  and  obliquely  equatorial  if  turned  round  on  its  axis  50°  or  60° ; the 
fourth,  equatorially  and  axially  under  the  same  treatment ; and  all  of  them,  if 
suspended  perpendicularly,  pointed  well,  vibrating  about  a final  fixed  position  which 
seemed  to  have  no  reference  to  the  form  of  the  cylinders.  In  all  these  cases  the  bis- 
muth was  strongly  diamagnetic  (2295,  &c.),  being  repelled  by  a single  magnetic 
pole,  or  passing  off  on  either  side  from  the  axial  line  between  two  poles.  A similar 
piece  of  finely-grained  or  granular  bismuth  was,  under  the  same  circumstances  and 
at  the  same  time,  affected  in  a perfectly  regular  manner,  taking  up  the  equatorial 
position  (2253.),  as  a body  simply  diamagnetic  ought  to  do.  The  cause  of  these 
variations  was  finally  traced  to  the  regularly  crystalline  condition  of  the  metallic 
cylinders. 

^ i.  CrystalUne  polarity  of  bismuth. 

2457.  Some  bismuth  was  crystallized  in  the  usual  manner  by  melting  it  in  a clean 
iron  ladle,  allowing  it  partly  to  congeal,  and  then  pouring  away  the  internal  fluid 
portion.  Pieces  so  obtained  were  then  broken  up  by  copper  hammers  and  tools,  and 
groups  of  the  crystals  separated,  each  group  or  piece  consisting  only  of  those  crystals 
which  were  symmetrically  arranged,  and  therefore  likely  to  act  in  one  direction.  If 
any  part  of  the  fragments  had  been  in  contact  with  the  iron  ladle,  it  was  cleared 
away  by  rubbing  on  sandstone  and  sand-paper.  Pieces  weighing  from  18  grains  to 
100  grains  were  thus  easily  obtained. 

2458.  The  electro-magnet  employed  in  the  first  instance  was  that  already  described 
(2247-),  having  moveable  terminations  which  supplied  either  conical,  round,  or  flat- 
faced poles.  That  the  suspension  of  the  bismuth  might  be  readily  effected  and  un- 
objectionable as  to  magnetic  influence,  the  following  arrangement  was  generally 
adopted.  A single  fibre  of  cocoon  silk,  from  12  to  24  inches  in  length,  was  attached 
to  a fit  support  above,  and  made  fast  below  to  the  end  of  a piece  of  fine,  straight, 
well-cleaned  copper  wire,  about  2 inches  in  length  ; the  lower  end  of  this  wire  was 
twisted  up  into  a little  head,  and  then  furnished  with  a pellat  of  cement,  made  by 
melting  together  a portion  of  pure  white  wax,  with  about  one-fourth  its  weight  of 
Canada  balsam.  The  cement  was  soft  enough  to  adhere  by  pressure  to  any  dry  sub- 
stance, and  sufficiently  hard  to  sustain  weights  up  to  300  grains,  or  even  more. 
When  prepared,  the  suspender  was  subjected  by  itself  to  the  action  of  the  magnet,  to 
ascertain  that  it  was  free  from  any  tendency  to  point,  or  be  affected ; without  which 
precaution  no  confidence  could  be  reposed  in  the  results  of  the  experiments. 

2459.  A piece  of  selected  bismuth  (2457.),  weighing  25  grains,  was  hung  up  between 
the  poles  of  the  magnet,  and  moved  with  great  freedom.  The  constituent  cubes 
were  associated  in  the  usual  manner,  being  attached  to  each  other  chiefly  in  the  line 
joining  two  opposite  solid  angles ; and  this  line  was  in  the  greatest  length  of  the 
piece.  The  instant  that  the  magnetic  force  was  on,  the  bismuth  vibrated  strongly 


CRYSTALLINE  POLARITY  AND  MAGNECRYSTALLIC  CONDITION  OF  BISMUTH.  3 


about  a given  line,  in  which,  at  last,  it  settled ; and  if  moved  out  of  that  position  it 
returned,  when  at  liberty,  into  it ; pointing  with  considerable  force,  and  having  its 
greatest  length  axial. 

2460.  Another  piece  was  then  selected,  having  a flatter  form,  which  when  subjected 
to  the  magnetic  power,  pointed  with  the  same  facility  and  force,  but  its  greatest 
length  was  equatorial : still  the  line  according  to  which  the  cubes  tended  to  associate 
diametrally,  was,  as  before,  in  the  axial  direction.  Other  pieces  were  then  taken  of 
different  forms,  or  shaped  into  various  forms  by  rubbing  them  down  on  stone,  but 
they  all  pointed  well ; and  took  up  a final  position,  which  had  no  reference  to  the 
shape,  but  was  manifestly  dependent  on  the  crystalline  condition  of  the  substance. 

2461.  In  all  these  cases  the  bismuth  was  diamagnetic,  and  strongly  repelled  by 
either  magnetic  pole,  or  from  the  axial  line.  It  was  affected  only  whilst  the  magnetic 
force  was  present.  It  set  in  a given  constant  position  perfectly  determinate  ; and,  if 
moved,  always  returned  to  it,  unless  the  extent  of  motion  was  above  90°,  and  then 
the  piece  moved  further  round  and  took  up  a new  position  diametrically  opposed  to 
the  former,  which  it  then  retained  with  equal  force,  and  in  the  same  manner.  This 
phenomenon  is  general  in  all  the  results  I have  to  refer  to,  and  I will  express  it  by 
the  word  diametral : — diametral  set  or  position. 

2462.  The  effect  occurs  with  a single  magnetic  pole,  and  it  is  then  striking  to  ob- 
serve a long  piece  of  a substance,  so  diamagnetic  as  bismuth,  repelled,  and  yet  at  the 
same  moment  set  round  with  force,  axially  or  end  on,  as  a piece  of  magnetic  substance 
would  do. 

2463.  Whether  the  magnetic  poles  employed  (2458.)  are  pointed,  round,  or  flat- 
faced, still  the  effect  on  the  bismuth  is  the  same : nevertheless,  the  form  of  the  poles 
has  an  important  influence  of  a subordinate  kind ; and  some  forms  are  much  more 
fitted  for  these  investigations  than  others.  When  pointed  poles  are  employed,  the 
lines  of  magnetic  force  (2149.)  rapidly  diverge,  and  the  force  itself  diminishes  in  in- 
tensity to  the  middle  distance  from  each  pole.  But  when  flat-faced  poles  are  used, 
though  the  lines  of  power  are  curved  and  vary  in  intensity  at  and  towards  the  edges 
of  the  flat  faces,  yet  there  is  a space  at  the  middle  of  the  magnetic  field  where  they 
may  be  considered  as  parallel  to  the  magnetic  axes,  and  of  equal  force  throughout. 
If  the  flat  faces  of  the  poles  be  square  or  circular,  and  their  distance  apart  about 
one-third  of  their  diameter,  this  space  of  uniform  power  is  of  considerable  extent. 
In  my  experience  the  central  or  axial  portion  of  the  magnetic  field  is  sensibly  weaker 
than  the  eircumjacent  parts ; but,  then,  there  is  a small  screw-hole  in  the  middle  of 
each  pole  face,  for  the  attachment  of  other  forms  of  termination. 

2464.  Now  the  law  of  action  of  bismuth,  as  a diamagnetic  body,  is,  that  it  tends  to 
go  from  stronger  to  weaker  places  of  magnetic  force  (2267.  2418.) ; but  as  a magne- 
crystallic  body  it  is  subject  to  no  effect  of  the  kind  ; and  is  as  powerfully  affected  by 
lines  of  equal  force  as  by  any  other.  So  a piece  of  amorphous  bismuth,  suspended 
in  a magnetic  field  of  uniform  power,  seems  to  have  lost  its  diamagnetic  force  alto- 

B 2 


4 DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


g-ether,  and  tends  to  acquire  no  motion  but  what  is  due  to  torsion  of  the  suspending 
fibre,  or  currents  of  air : but  a piece  of  regularly  crystallized  bismuth  is,  in  the  same 
situation,  very  powerfully  affected  by  virtue  of  its  magnecrystallic  condition. 

2465.  Hence  the  great  value  of  a magnetic  field  of  uniform  force;  and,  if,  here- 
after, in  the  extension  of  these  investigations  to  bodies  having  only  a small  degree  of 
crystalline  power,  a perfectly  uniform  field  should  be  required,  it  could  easily  be 
given  by  making  the  form  of  the  pole  face  somewhat  convex,  and  rounded  at  the 
edges  more  or  less.  The  required  shape  could  be  ascertained  by  calculation,  or 
perhaps  better  in  practice,  by  the  use  of  a little  test  cylinder  of  bismuth  in  the  gra- 
nular or  amorphous  state,  or  of  phosphorus. 

2466.  In  addition  to  these  observations  it  may  be  remarked,  that  small  crystals, 
or  masses  of  crystals,  and  such  as  approach  in  their  general  shape  to  that  of  a cube 
or  a sphere,  are  better  than  large  or  elongated  pieces  ; inasmuch,  as  if  there  be  irre- 
gularities in  the  force  of  a magnetic  field,  such  pieces  are  less  likely  to  be  affected  by 
them. 

2467-  When  the  crystal  of  bismuth  is*  in  a magnetic  field  of  equal  strength,  it  is 
equally  affected  whether- it  be  in  the  middle  of  the  field  or  close  up  to  one  or  the 
other  magnetic  pole  ; i.  e.  the  number  of  vibrations  in  equal  times  appears  to  be  equal. 
Much  care,  however,  is  required  in  estimating  it  by  such  means,  because,  from  the 
occurrence  of  two  positions  of  unstable  equilibrium  in  the  equatorial  direction,  the 
vibrations  in  large  arcs  are  much  Slower  than  those  in  small  arcs ; and  it  is  difficult 
in  different  eases  to  adjust  them  to  the  same  extent  of  vibration. 

2468.  Whether  the  bismuth  be  in  a field  of  intense  magnetic  force  or  one  of  feeble 
powers  ; whether  the  magnetic  poles  are  close  up  to  the  piece,  or  are  opened  out  until 
they  are  five  or  six  inches  or  even  a foot  asunder;  whether  the  bismuth  be  in  the 
line  of  maximum  force,  or  raised  above,  or  lowered  beneath  it;  whether  the  electric 
current  be  strong  or  weak,  and  the  magnetic  force,  therefore,  more  or  less  in  that 
respect ; if  the  bismuth  be  affected  at  all  it  is  always  affected  in  the  same  manner. 

2469.  The  results  are,  altogether,  very  different  from  those  produced  by  diamag- 
netic action  (2418).  They  are  equally  distinct  from  those  dependent  on  ordinary 
magnetic  action.  They  are  also  distinct  from  those  discovered  and  described  by 
Plucker,  in  his  beautifid  researches  into  the  relation  of  the  optic  axis  to  magnetic 
action ; for  there  the  force  is  equatorial,  whereas  here  it  is  axial.  So  they  appear  to 
present  to  us  a new  force,  or  a new  form  of  force  in  the  molecules  of  matter,  which, 
for  convenience  sake,  I will  conventionally  designate  by  a new  word,  as  the  magne- 
crystallic force. 

2470.  The  direction  of  tliis  force  is,  in  relation  to  the  magnetic  field,  axial  and  not 
equatorial-,  this  is  proved  by  several  considerations.  Thus,  when  a piece  of  re- 
gularly crystallized  bismuth  was  suspended  in  the  magnetic  field,  it  pointed  ; keep- 
ing it  in  this  position,  the  point  of  suspension  was  removed  90°  in  the  equatorial 
plane  (2252.),  so  that  when  again  freely  suspended,  the  line  through  the  crystal. 


3IAGNECRYSTALL1C  CONDITION  OF  BISMUTH — AXIALITY. 


O 


which  was  before  horizontal  in  the  equatorial  plane,  was  now  vertical;  the  piece 
again  pointed,  and  generally  with  more  force  than  before.  The  line  passing  through 
the  crystal,  coincident  with  the  magnetic  axis,  may  now  be  taken  as  the  line  of  force  ; 
and  if  the  process  of  a quarter  revolution  in  the  equatorial  plane  be  repeated,  how- 
ever often,  the  crystal  still  continues  to  point  with  the  assumed  line  of  force  in  the 
magnetic  axis,  and  with  a maximum  degree  of  power.  But  now,  if  the  point  of 
suspension  be  removed  90°  in  the  plane  of  the  axis,  i.  e.  to  the  end  of  the  assumed 
line  of  force,  so,  that  when  the  crystal  is  again  freely  suspended  this  line  is  vertical ; 
then,  the  crystal  presents  its  peculiar  effect  at  a minimum,  being  almost  or  entirely 
devoid  of  pointing  power,  and  exhibits  in  relation  to  the  magnet,  only  the  ordinary 
diamagnetic  force  (2418.). 

2471.  Now  if  the  power  had  been  equatorial  and  polar,  its  maximum  effect  would 
not  have  been  produced  by  a change  of  the  point  of  suspension  through  90°  in  the 
equatorial  plane,  but  by  the  same  change  in  the  axial  plane,  and  any  similar  change 
after  that  in  the  axial  plane,  would  not  have  disturbed  the  maximum  force  ; whereas 
a single  change  of  90°  in  the  equatorial  plane,  would  have  brought  the  line  of  force 
vertical  (as  in  Plucker’s  case  of  Iceland  spar),  and  reduced  the  results  to  a mini- 
mum or  zero. 

2472.  The  directing  force,  therefore,  and  the  set  of  the  crystal  are  in  the  axial  di- 
rection. This  force  is,  doubtless,  resident  in  the  particles  of  the  crystal.  It  is  such, 
that,  the  crystal  can  set  with  equal  readiness  and  permanence  in  two  diametral  po- 
sitions : and  that  between  these  there  are  two  positions  of  equatorial  equilibrium, 
which  are,  of  course,  unstable  in  their  nature.  Either  end  of  the  mass  or  of  its  mole- 
cules, is  to  all  intents  and  purposes,  both  in  these  phenomena,  and  in  the  ordinary 
results  of  crystallization,  like  the  other  end  ; and  in  many  cases,  therefore,  the  words 
axial  and  axiality  would  seem  more  expressive  than  the  words  polar  and  polarity. 
In  presenting  the  ideas  to  my  own  mind,  I have  found  the  meaning  belonging  to  the 
former  words  the  most  useful. 

2473.  On  placing  the  metal  in  other  positions,  and  therefore  in  a constrained  con- 
dition, no  alteration  of  the  state  or  power  of  the  bismuth,  either  in  force  or  direction, 
is  produced  by  the  power  of  the  magnet,  however  strong  its  enforcement  or  long  its 
continuance. 

2474.  It  is  difficult  readily  to  describe  the  position  of  this  force  in  relation  to  the 
crystal,  though  most  easy  to  ascertain  it  experimentally.  The  form  of  the  bismuth 
crystals  is  said  to  be  that  of  a cube,  and  of  its  primitive  particle  a regular  octohedron. 
To  me  the  crystals  do  not  seem  to  be  cubes,  but  either  rhomboids  or  rhombic  prisms, 
approaching  very  nearly  to  cubes.  My  measurements  were  very  imperfect  and  the 
crystals  not  regular ; but  as  an  average  of  several  observations,  the  planes  were  in- 
clined to  each  other  at  angles  of  91^°  and  88^°;  and  the  boundary  lines  of  a plane 
at  87^°  and  92-g°.  Whatever  be  the  true  form,  it  is  manifest  upon  inspection,  that  the 
aggregating  force  tends  to  produce  crystals  having  more  or  less  of  the  rhomboidal 


6 DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


shape  and  rhombic  planes  ; and  that  these  crystals  run  together  in  symmetric  groups, 
generally  in  the  direction  of  their  longest  diameters.  Now  the  line  of  magnecrystalUc 
force  almost  always  coincides  with  this  direction  where  the  latter  is  apparent. 

2475.  The  cleavage  of  bismuth  crystals  removes  the  solid  angles  and  replaces  them 
by  planes ; so  that  there  are  four  directions  producing  the  octohedron.  These  clea- 
vages are  not  (in  my  experience)  made  with  equal  facility,  nor  do  they  produce  planes 
equally  bright  and  perfect.  Two,  and  more  frequently  one,  of  these  planes  is  more 
perfect  than  the  others  ; and  this,  the  most  perfect  plane,  is  that  which  is  produced  at 
the  most  acute  solid  angle  (2474.) ; and  is  generally  easily  recognized.  When  a 
bismuth  crystal  presents  many  planes  of  cleavage  and  is  suspended  in  the  magnetic 
field,  one  of  these  planes  faces  towards  one  of  the  magnetic  poles,  and  its  corre- 
sponding plane,  if  it  be  there,  towards  the  other ; so  that  the  line  of  magnecrystallic 
force  is  perpendicular  to  this  plane:  and  this  plane  corresponds  to  the  one  which  I 
have  already  described  as  being,  generally,  the  most  perfect,  and  replacing  the  acute 
angle  of  the  crystal. 

2476.  A single  crystal  of  bismuth  was  selected  and  cut  out  from  the  mass  by 
copper  tools,  and  the  places  where  it  had  adhered  were  rubbed  down  on  sand-paper, 
so  as  to  give  the  fragment  a cube-like  form  with  six  planes ; four  of  these  planes 
were  natural.  One  of  the  solid  angles,  expected  to  be  that  terminating  or  in  the  di- 
rection of  the  line  of  magnecrystallic  force,  was  removed,  so  as  to  expose  a small 
cleavage  plane,  which  was  bright  and  perfect,  as  also  was  expected.  When  suspended 
in  the  magnetic  field  with  this  plane  vertical,  the  crystal  instantly  pointed  with  con- 
siderable force,  and  with  the  plane  towards  either  one  or  the  other  magnetic  pole ; 
so  that  the  magnecrystallic  axis  appeared  now  to  be  horizontal  and  acting  with  its 
greatest  power.  When  this  axial  line  was  made  vertical,  and  the  plane  therefore 
horizontal,  the  position  being  carefully  adjusted,  the  crystal  did  not  point  at  all. 
Being  now  suspended  in  succession  at  all  the  angles  and  faces  of  the  cube,  it  always 
pointed  with  more  or  less  force ; but  always  so  that  a line  drawn  perpendicularly 
through  the  indicating  cleavage  plane  (representing  therefore  the  line  of  force)  was  in 
the  same  vertical  plane  as  that  including  the  magnetic  axis : and,  finally,  when  the 
bright  cleavage  plane  was  horizontal  and  the  line  of  directive  force  therefore  vertical, 
inclining  it  a little  in  a given  direction,  would  make  any  given  part  of  the  crystal 
point  to  the  magnetic  poles. 

2477-  A group  of  bismuth  crystals,  the  apex  of  which  was  terminated  by  a single 
small  cleavage  facet,  was  found  to  give  the  same  results. 

2478.  Occasionally  groups  of  crystals  (2457.)  occurred  which  did  not  seem  capable 
of  being  placed  in  some  one  position  in  which  they  lost  all  directive  power,  but 
seemed  to  retain  a minimum  degree  of  force.  It  is  very  unlikely,  however,  that  all 
the  groups  should  be  perfectly  symmetric  in  the  arrangement  of  their  parts.  It  is 
more  surprising  that  they  should  be  so  distinct  in  their  action  as  they  are.  In 
reference  to  bismuth,  and  many  other  bodies,  it  is  probable  that  magnetic  force  will 


LAW  OF  MAGNECRYSTALLIC  ACTION. 


7 


give  a more  important  indication  in  relation  to  the  essential  and  real  crystalline 
structure  of  the  mass  than  its  form  can  do. 

24/9.  I have  already  stated  that  the  magnecrystaUic  force  does  not  manifest  itself 
by  attraction  or  repulsion,  or,  at  least,  does  not  cause  approach  or  recession,  but 
gives  position  only.  The  law  of  action  appears  to  be,  that,  the  line  or  axis  of  magne- 
CRVSTALLic  fovce  (being  the  resultant  of  the  action  of  all  the  molecules),  tends  to  place 
itself  parallel,  or  as  a tangent,  to  the  magnetic  curve  or  line  of  magnetic  force,  passing 
through  the  place  where  the  crystal  is  situated. 


2480.  I now  broke  up  masses  of  bismuth  which  had  been  melted  and  solidified  in 
the  ordinary  way,  and,  selecting  those  fragments  which  appeared  to  be  most  regularly 
crystallized,  submitted  them  to  experiment.  It  was  almost  impossible  to  take  a small 
piece  which  did  not  obey  the  magnet  and  point  more  or  less  readily.  By  selecting 
the  thin  plates  with  perfect  cleavage  planes,  I readily  obtained  specimens  which  cor- 
responded in  all  respects  with  the  crystals  ; but  thicker  plates  or  angular  pieces  often 
proved  complicated  in  the  results,  though  apparently  simple  and  regular  as  to  form. 
Occasionally,  the  cleavage  plane,  which  I have  beforehand  taken  for  that  perpendi- 
cular to  the  line  of  force  (2475.),  has  proved  not  to  be  the  plane  supposed;  but,  after 
observing  experimentally  the  direction  of  the  magnecrystaUic  power,  I have  always 
either  found,  or  else  obtained  by  cleavage,  a plane  corresponding  to  it,  possessing 
the  appearance  and  character  before  described  (2475.).  Bismuth  plates  from  the 
one-twentieth  to  the  one-tenth  of  an  inch  in  thickness,  and  bounded  by  parallel  and 
similar  planes,  when  broken  up  often  proved,  upon  ocular  examination,  to  be  com- 
pounded and  irregular. 

2481.  When  a well-selected  plate  of  bismuth  (mine  are  about  0-3  of  an  inch  in 
length  and  breadth,  and  0‘05,  more  or  less,  in  thickness)  is  hung  up  by  the  edge  in  the 
magnetic  field,  it  vibrates  and  points,  presenting  its  faces  to  the  magnetic  poles,  and 
setting  diametrally  (2461.).  By  whatever  part  of  the  edge  it  is  suspended,  the 
same  results  follow.  But  if  it  be  suspended  horizontally,  the  cleavage  planes  of  the 
fragment  and  of  the  magnetic  axis  being  parallel  to  the  plane  of  motion  of  the  plate, 
then  it  is  perfectly  indifferent ; for  then  the  line  of  magnecrystaUic  force  is  perpen- 
dicular to  the  line  of  magnetic  force  in  every  position  that  it  can  take. 

2482.  But  if  the  plate  be  inclined  only  a very  small  quantity  from  this  position,  it 
points,  and  that  with  more  force  as  the  planes  become  more  nearly  vertical  (2475.) ; 
and  the  phenomena  before  described  with  a crystal  (2476.),  can  here  be  obtained 
with  a fragment  from  a mass,  and  any  part  of  the  edge  of  the  plate  made  to  point 
axially,  by  elevating  or  depressing  it  above  or  below  the  horizontal  plane. 

2483.  If  a number  of  these  crystalline  plates  be  selected  at  the  magnet,  they  may 
afterwards  be  built  up  together,  with  a little  good  cement  (2458.),  into  a mass  which 
has  perfectly  regular  magnecrystaUic  action ; and  in  that  respect  resembles  the 


8 DR.  FARADAY’S  EXPERhMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


crystals  before  spoken  of  (2459.  2468.  2476.).  In  this  manner,  also,  the  diamagnetic 
effect  of  the  bismuth  may  be  neutralized  ; for  it  is  easy  to  build  up  a prism  whose 
breadth  and  thickness  is  equal,  and  this  being-  hung  with  the  length  vertical,  points 
well  and  without  any  interference  of  diamagnetic  action. 

2484.  By  placing  three  equal  plates  at  right  angles  to  each  other,  a system  is  ob- 
tained, which  has  lost  all  power  of  pointing  under  the  influenee  of  the  magnet,  the 
force  being,  in  every  direction,  neutralized.  This  represents  the  case  of  finely 
ciystallized  or  amorphous  bismuth.  The  same  result  (having  the  same  nature)  may 
be  obtained  by  taking  a selected  uniform  mass  of  crystals  (2457.)?  melting  it  in  a 
glass  tube  and  resolidifying  it ; unless  the  crystallization  is  large  and  distinct,  which 
rarely  happens,  the  piece  obtained  is  apparently  without  magnecrystallic  force.  A 
like  result  is  also  obtained  by  breaking  up  the  crystal  and  putting  the  small  frag- 
ments or  powder  into  a tube,  and  submitting  the  whole  to  tlie  force  of  the  magnet. 


2485.  These  experiments  on  bismuth  are  not  difficult  of  repetition  ; for,  except 
those  which  require  the  sudden  production  or  cessation  of  the  magnetic  force,  the 
whole  may  be  repeated  with  an  ordinary  horse-shoe  magnet.  A magnet,  with  which 
I have  wrought  considerably,  consists  of  seven  bars  placed  side  by  side,  and  being 
fixed  in  a box  with  the  poles  upwards,  presents  two  magnet  cheeks,  an  inch  and  a 
quarter  apart,  between  which  is  the  magnetic  field,  having  the  lines  of  force  in  a 
horizontal  direction.  The  poles  of  the  magnet  should  be  covered,  each  with  paper, 
to  prevent  communication  of  particles  of  iron  or  rust.  The  best  place  for  the  piece 
of  bismuth  is,  of  course,  between  the  poles;  not  level  however  with  their  tops,  but 
from  0'4  to  TO  inch  lower  down  (2463.),  that  the  effect  of  flat-faced  poles  may  be 
obtained.  If  it  be  desired  to  strengthen  the  lines  of  magnetic  force,  this  may  be  done 
by  introducing  a piece  of  iron  between  the  poles  of  the  magnet,  and  so,  by  virtually 
causing  them  to  approach,  lessen  the  width  of  the  magnetic  field  between  them, 

2486.  The  magnet  I used  would  sustain  30  lbs.  at  the  keeper ; but  employing 
small  pieces  of  bismuth,  I have  easily  obtained  the  effects  with  magnets  weighing 
themselves  not  more  than  7 ounces,  and  able  to  sustain  only  22  ounces  ; so  that  the 
experiments  are  within  the  reach  of  every  one. 


2487.  Whilst  the  crystal  of  bismuth  is  in  the  magnetic  field,  it  is  affected  very  di- 
stinctly, and  even  strongly,  by  the  near  approximation  of  soft  iron  or  magnets,  and 
after  the  following  manner.  Let  fig.  1 represent  in  plan  the  Fig-  T 

position  of  the  two  chief  magnetic  poles,  and  of  a piece  of 
crystallized  bismuth  between  them,  which,  by  its  magne- 
crystallic condition,  points  axially.  Then,  if  a piece  of  soft 
iron  be  applied  against  the  cheek  of  the  pole,  as  at  e,  and 
also  near  to  the  bismuth,  as  at  a,  it  will  affect  the  latter  and 


INFLUENCE  OF  IRON  IN  THE  MAGNETIC  FIELD. 


9 


cause  its  approach  to  the  iron.  If  the  iron  be  applied  in  a similar  manner  at  f,  g, 
or  h,  it  will  have  a like  result  in  causing'  motion  of  the  bismuth  ; and  the  parts 
marked  h,  c and  d,  will  in  turn  approach  it,  seeming'  to  be  attracted.  If  the  soft 
iron  do  not  touch  the  magnetic  pole,  but  be  held  between  it  and  the  bismuth  so  as 
to  represent  generally  the  same  positions,  the  same  effects,  but  in  a weaker  degree, 
are  produced. 

2488.  Though  these  motions  seem  to  indicate  an  effect  of  attraction,  I do  not 
believe  them  to  be  due  to  any  such  cause,  but  simply  to  the  influence  of  the  law  of 
action  (2479.)  before  expressed.  The  previously  uniform  condition  of  the  magnetic 
field  is  destroyed  by  the  presence  of  the  iron ; lines  of  magnetic  force,  of  greater  in- 
tensity than  the  others,  proceed  from  the  angle  a of  the  iron  in  the  position  repre 
sented,  or  from  the  corresponding  angles  in  the  other  positions  (the  shape  of  the  pole 
now  approximating  more  or  less  to  the  conical  or  pointed  form),  and  therefore  the 
crystal  of  bismuth  moves  round  on  the  axis  of  suspension,  that  it  may  place  the  line 
of  magnecrystallic  force  parallel  or  as  a tangent  to  the  resultant  of  the  magnetic 
forces  which  pass  through  its  mass. 

2489.  When  in  place  of  the  group  of  crystals  a crystalline  plate  of  bismuth  (2481.) 

is  employed,  the  appearances  produced  under  similar  circumstances,  are  those  of 
repulsion  ; for  if  fig.  2 be  allowed  to  represent  this  state  of  Fig.  2. 

things,  the  piece  of  iron  applied  at  e causes  the  plate  to 
recede  from  it  at  a,  or  if  applied  at  f,  g,  or  A,  it  causes  re- 
cession of  the  bismuth  from  it  at  the  points  A,  c,  and  d. 

Now  though  these  effects  look  like  repulsion,  they  are,  as  I 
conclude,  nothing  more  than  the  consequences  of  the  en- 
deavour which  the  bismuth  makes,  under  the  law  before  expressed  (2479.),  to  place 
the  magnecrystallic  line  of  force  parallel  to,  or  as  a tangent  to  the  resultant  of  mag- 
netic force  passing  through  the  bismuth. 

2490.  A piece  of  iron  wire  about  inch  long,  and  O'l  or  0'2  of  an  inch  thick, 
being  held  in  the  equatorial  plane  to  the  edge  of  the  plate 
(fig.  3),  did  not  alter  its  position;  but  if  the  end  e were  in- 
clined to  either  pole,  the  plate  began  to  move,  and  moved 
most  when  the  iron  touched  the  pole  as  in  the  figure. 

When  it  approached  or  touched  the  N pole,  the  inclina- 
tion of  the  crystal  plate  of  bismuth  was  as  indicated  by 
the  dotted  figure.  When  it  touched  the  S,  the  inclina- 
tion was  the  contrary  way.  If  the  end  e were  kept  in 
contact  with  the  N pole,  and  the  other  end  of  the  soft  iron  rod  placed  in  the  position 
m,  the  bismuth  was  not  affected ; but  if  then  this  subsidiary  pole  were  moved  the 
one  way  or  the  other  towards  the  edge  of  the  plate,  the  latter  turned  as  the  pole 
moved,  always  tending  to  keep  its  face  towards  it,  and  evidently  by  the  tendency  of 
the  magnecrystallic  axis  to  place  itself  parallel  to  the  resultant  of  magnetic  force 


MDCCCXLTX. 


c 


10  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

passing  through  the  bismuth.  The  same  results  were  obtained  with  the  crystal 
(2487.)  under  similar  circumstances,  and  corresponding  results  were  obtained  when 
the  soft  iron  rod  was  applied  betvveen  the  S cheek  of  the  magnet  and  the  bismuth. 
The  like  effects  were  also  obtained  with  plates  of  arsenic  and  antimony. 

2491.  When  a magnet  is  used  instead  of  soft  iron,  corresponding  effects  are  pro- 
duced ; only,  it  must  be  remembered,  that  if  the  chief  magnet  be  very  powerful,  it 
may  often  neutralize,  and  even  change,  the  magnetism  of  the  small  approximated 
magnet ; and  this  can  happen  with  the  latter  (as  to  external  influence)  whilst 
in  the  magnetic  field,  even  though  when  withdrawn  it  may  appear  to  remain  un- 
altered. 

2492.  Thus,  when  the  plate  of  bismuth  was  suspenfled  between  the  cheeks  of  the 
horse-shoe  magnet  (2485.),  fig.  2,  and  the  north  pole  of  a small  magnet  (the  blade  of 
a pocket-knife)  was  placed  at  a or  6,  it  caused  recession  of  the  part  of  the  bismuth 
near  it,  and  precisely  for  the  same  reasons  as  those  that  existed  when  the  soft  iron 
was  there.  When  the  extra  pole  was  placed  at  c or  d,  the  action  was  more  feeble 
than  in  the  former  case,  and  consisted  in 'an  approximation  of  that  part  of  the  bismuth 
to  the  pole.  As  this  position  of  the  subordinate  pole  would  terminate  and  neutralize 
certain  of  the  lines  of  magnetic  force  proceeding  from  the  south  pole  of  the  horse-shoe 
magnet,  so  the  resultant  of  the  lines  of  force  passing  through  the  bismuth  would  be 
changed  in  direction,  being  rendered  oblique  to  their  former  course,  and  precisely 
in  the  manner  represented  by  the  motion  of  the  bismuth,  in  its  tendency  to  place  its 
line  of  force  parallel  with  them  in  their  new  position. 

2493.  An  approximated  south  pole  caused  motions  in  the  contrary  direction. 

2494.  When  the  subordinate  pole  was  applied  to  the  edge  of  the  plate,  the  little 
magnet  being  in  the  equatorial  position  (fig.  3),  then  instead  of  being  neutral,  as  the 
iron  was,  it  caused  the  plate  to  move  in  a tangential  direction,  either  to  the  right  or 
the  left,  according  as  it  was  either  a south  or  a north  pole,  just  indeed  as  the  iron  did 
when,  by  inclining  it,  the  approximated  end  became  a pole  (2490.).  This  effect  was 
shown  in  a still  more  striking  degree  by  using  the  crystal  of  bismuth  (2487-),  because, 
from  its  form  and  position  the  magnetic  curves  most  affected  by  the  extra  pole  were 
more  included  in  the  bismuth  than  when  the  plate  was  used. 

2495.  Innumerable  variations  of  these  motions  may  be  caused,  and  appearances 
of  attraction  or  repulsion,  or  tangential  action  be  obtained  at  pleasure  by  the  use  of 
crystals  having  the  magnecrystallic  axis  corresponding  with  their  length,  or  plates 
where  it  accords  with  their  thickness ; and  either  permanent  or  temporary  subsidiary 
magnetic  poles.  By  making  the  moveable  pole  travel  slowly  round  the  bismuth 
from  the  neutral  point  m to  the  other  neutral  point  7i,  fig.  3,  a summary  of  the  whole 
can  be  obtained,  and  it  is  found  that  they  all  resolve  themselves  into  the  general 
law  before  expressed  (2479.) : the  magnecrystallic  axis  and  the  resultant  of  magnetic 
force  passing  through  the  bismuth,  tending  to  become  parallel. 

2496.  Hence  a small  crystal  or  plate  of  bismuth  (or  arsenic  (2532.))  may  become 


CRYSTALS  OF  BISMUTH  IN  VARIOUS  MEDIA. 


11 


a very  useful  and  important  indicator  of  the  direction  of  the  lines  of  force  in  a mag- 
netic field,  for  at  the  same  time  that  it  takes  up  a position  showing  their  course,  it 
does  not  by  its  own  action  tend  sensibly  to  disturb  them. 

249/ . Many  of  these  motions  are  similar  to,  and  have  relation  with,  those  described 
by  Plucker,  Reich,  and  others,  as  obtained  by  the  action  of  iron  and  magnets  on 
bismuth,  in  its  simple  diamagnetic  condition.  These  results  are  by  them  and  others 
considered  as  indicating  that  the  bismuth,  as  I had  originally  supposed  (2429,  &c.), 
has  really  in  its  diamagnetic  state,  a magnetic  condition  the  reverse  of  that  of  iron. 
I am  not  acquainted  with  all  of  them,  or  with  the  reasoning  thereon  (being  in  the 
German  language) ; but  such  as  I am  aware  of,  and  have  reobtained,  seem  to  me  to 
be  simple  results  of  the  law  I formerly  laid  down  (2267.  2418.),  namely,  that  diamag- 
netic bodies  tend  to  proceed  from  stronger  to  weaker  places  of  magnetic  force : and 
give  no  additional  or  other  proof  of  the  assumed  reverse  polarity  of  bismuth  than  the 
former  cases  of  action  which  1 had  given,  coming  under  that  law. 


2498.  Supposing  that  the  intervening  or  surrounding  matter  might,  in  some 
manner,  affect  the  magnecrystallic  action  of  bismuth  and  other  bodies,  I fixed  the 
magnetic  poles  at  a given  distance  (about  two  inches)  asunder,  suspended  a crystal 
of  bismuth  in  the  middle  of  the  magnetic  field,  and  observed  its  vibrations  and  set. 
Then,  without  any  other  change,  I introduced  screens  of  bismuth,  being  blocks  about 
two  inches  square  and  0'7o  of  an  inch  in  thickness,  between  the  poles  and  the  crystal, 
but  I could  not  perceive  that  any  change  in  the  phenomena  was  produced  by  their 
presence. 

2499.  The  bismuth  crystal  (2459.)  was  suspended  in  water  between  the  magnetic 
poles  of  the  horse-shoe  magnet.  It  set  well  in  accordance  with  the  general  law  (2479.), 
and  it  took  five  revolutions  of  the  torsion  index  at  the  upper  end  of  the  suspending 
silk  filament  to  displace  it,  and  cause  it  to  turn  into  the  diametral  position.  This  is, 
as  well  as  I could  observe  the  results,  the  same  amount  of  torsion  force  required  to 
effect  its  displacement  when  the  crystal  was  placed  in  the  same  position,  but  sur- 
rounded with  air  only. 

2500.  The  same  bismuth  was  then  suspended  in  a saturated  solution  of  proto- 
sulphate of  iron  (adapted  as  a magnetic  medium),  it  set  as  before  with  apparently  no 
change  of  any  kind  ; and  when  the  torsion  force  was  put  on,  it  still  required  five 
turns  of  the  index,  as  before,  to  cause  the  displacement  of  the  crystal,  and  its  passage 
into  the  diametral  position. 

2501.  Whether  therefore  crystals  of  bismuth  be  immersed  in  air,  or  water,  or  solu- 
tion of  sulphate  of  iron,  or  placed  between  thick  masses  of  bismuth,  if  they  be  subject 
to  the  same  magnetic  force,  the  magnecrystallic  force  exerted  by  them  is  the  same 
both  in  nature,  direction  and  amount. 


12  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


2502.  It  seemed  possible  and  probable  that  magnetic  force  might  affect  the  cry- 
stallization of  bismuth,  if  not  of  other  bodies.  For,  as  the  force  affects  the  mass  of 
a crystal  by  that  power  which  its  particles  possess,  and  which  they  give  to  the  crystal 
as  a whole  by  their  polar  (or  axial  (2472.))  and  symmetric  condition  ; and,  as  the 
final  position  of  the  crystalline  mass  in  the  magnetic  field  may  be  considered  as  that 
of  the  least  constraint,  so  it  was  likely  enough  that,  if  the  bismuth  in  a fluid  state 
were  placed  under  the  influence  of  the  magnetism,  the  individual  particles  would 
tend  to  assume  one  and  the  same  axial  condition,  and  the  crystalline  arrangement 
and  direction  of  the  mass  upon  its  solidification,  be  in  some  degree  determined  and 
under  government. 

2503.  Some  bismuth,  therefore,  was  fuzed  in  a glass  tube  and  held  in  a fixed  posi- 
tion in  the  strong  magnetic  field  until  it  had  become  solid  ; then,  being  removed  from 
the  glass,  it  was  suspended  so  that  it  might  assume  the  same  position  under  the  in- 
fluence of  the  magnet ; but  no  signs  of  magnecrystallic  force  were  evident.  It  was 
not  expected  that  the  whole  would  become  regularly  crystallized,  but  that  a difference 
between  one  direction  and  another  might  appear.  Nothing  of  the  kind  however 
occurred,  whatever  the  direction  in  which  the  piece  was  suspended ; and  when  it 
was  broken  open,  the  crystallization  within  was  found  to  be  small,  confused,  and  in 
all  directions.  Perhaps  if  longer  time  were  allowed,  and  a permanent  magnet  used, 
a better  result  might  be  obtained.  I had  built  many  hopes  upon  the  process,  in  re- 
ference to  the  crystalline  condition  of  gold,  silver,  platina,  and  the  metals  generally, 
and  also  in  respect  of  other  bodies. 


2504.  I cannot  find  that  crystals  of  bismuth  acquire  any  power,  either  tempo- 
rary or  permanent,  which  they  can  bring  away  from  the  magnetic  field.  I held 
crystals  in  different  positions  in  the  field  of  intense  action  of  a powerful  electro- 
magnet, having  conical  terminations  very  near  to  each  other  ; and,  after  some  time, 
removed  them  and  applied  them  instantly  to  a very  delicate  astatic  magnetic  needle  ; 
but  I could  not  perceive  that  they  had  the  least  extra  effect  upon  it,  because  of  such 
treatment. 

2505.  As  a crystal  of  bismuth  is  subject  to,  and  obeys  the  influence  of,  the  lines  of 
magnetic  force  (24/9.),  so  it  follows  that  it  ought  to  obey  even  the  earth’s  action,  and 
point,  though  with  a very  feeble  degree  of  power.  I have  suspended  a good  crystal 
by  a single  long  filament  of  cocoon  silk,  and  sheltered  it  as  well  as  1 could  from 
currents  of  air  by  concentric  glass  tubes,  and  I think  have  observed  indications  of  a 
set  or  pointing.  The  crystal  was  so  hung  that  the  magnecrystallic  axis  made  the 
same  angle  with  the  horizontal  plane  (about  70°)  as  the  magnetic  dip,  and  the  indi- 
cation was,  that  the  axis  and  the  dip  tended  to  coincide  : but  the  experiments  require 
careful  repetition. 

2506.  A more  important  point,  as  to  the  nature  of  the  polar  or  axial  forces  of  bis- 


MAGNECRYSTALLIC  CONDITION  OF  ANTIMONY. 


13 


muth,  is  to  know  whether  two  crystals,  or  uniformly  crystallized  masses  of  bismuth, 
can  mutually  affect  each  other  ; and  if  so,  what  the  nature  of  these  affections  are  ? 
what  is  the  relation  of  the  equatorial  and  terminal  parts?  and  what,  the  direction  of 
the  forces  ? I have  made  many  experiments,  in  relation  to  this  subject,  both  in  and 
out  of  the  magnetic  field,  but  obtained  only  negative  results.  I employed  however 
small  masses  of  bismuth,  and  it  is  my  purpose  to  repeat  and  extend  them  at  a more 
convenient  season  with  larger  masses,  built  up,  if  necessary,  in  the  manner  already 
described  (2483.). 

250/.  I need  hardly  say  that  a crystal  of  bismuth  ought  to  point  in  a helix  or  ring 
of  wire  carrying  an  electric  current,  and  so  that  its  magnecrystrallic  axis  should  be 
parallel  to  the  axis  of  the  ring  or  helix.  This  I find  experimentally  to  be  the  case. 

^ ii.  Crystalline  Polarity  of  Antimony. 

2508.  Antimony  is  a magnecrystallic  body.  Some  crystalline  masses,  procured  in 
the  manner  before  described  (2457.)?  were  broken  up  with  copper  tools,  and  some 
excellent  groups  of  crystals  were  obtained,  weighing  from  ten  to  twenty  g'rains  each, 
in  which  all  the  constituent  crystals  appeared  to  be  uniformly  placed.  The  individual 
crystals  were  very  good  on  the  whole,  and  much  more  frequently  full  at  the  faces 
and  complete  than  those  of  bismuth.  They  were  very  bright,  having  a steel-gray  or 
silvery  appearance,  and  to  the  eye  appeared  more  surely  as  cubes  than  bismuth, 
though  here  and  there  distinctly  rhomboidal  faces  presented  themselves.  Planes  of 
cleavage  can  be  made  to  replace  the  solid  angles  ; and,  as  with  bismuth,  there  is  one 
plane  generally  brighter  and  more  perfect  than  the  others. 

2509.  In  the  first  place,  it  was  ascertained  that  all  these  crystals  were  diamagnetic? 
and  strongly  so. 

2510.  In  the  next  it  was  ascertained,  as  with  bismuth,  that  all  of  them  exhibited 
the  magnecrystallic  phenomena  with  considerable  power,  showing  the  existence  of  a 
line  of  force  (2470.),  vvhich,  when  placed  vertically,  left  the  crystal  free  to  move  in 
any  direction  (2476.)  ; but  when  placed  horizontally,  caused  the  crystal  to  point,  and 
in  so  doing  took  up  its  own  position  parallel  to  the  resultant  of  magnetic  force  pass- 
ing through  the  crystal  (2479.).  This  line  proceeded,  as  in  bismuth,  from  one  of  the 
solid  angles  to  the  opposite  one,  and  was  perpendicular  to  the  bright  cleavage  plane 
just  spoken  of  (2508.). 

2511.  So,  generally,  the  action  of  the  magnet  upon  these  crystals  was  the  same  as 
upon  the  crystals  of  bismuth  ; but  there  are  some  points  of  variation  which  require 
to  be  more  distinctly  stated  and  distinguished. 

2512.  In  the  first  place,  when  the  magnecrystallic  axis  was  horizontal,  and  a certain 
crystal  used,  upon  the  evolution  of  the  magnetic  force,  the  crystal  went  up  to  its  posi- 
tion slowly,  and  pointed  as  with  a dead  set.  If  the  crystal  were  moved  from  this 
position  on  either  side,  it  returned  to  it  at  once  : there  was  no  vibration.  Other 
crystals  did  the  same  imperfectly ; and  others  again  made  one  or  perhaps  two  vibra- 


14  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

tions,  but  all  appeared  as  if  they  were  moving  in  a thick  fluid,  and  were,  in  that 
respect,  utterly  unlike  bismuth,  in  the  freedom  and  mobility  with  which  it  vibrated 
(2459.). 

2513.  In  the  next  place,  when  the  crystals  were  so  suspended  as  to  have  the  mag- 
necrystallic  axis  vertical,  there  was  no  pointing  nor  any  other  signs  of  magnecrystallic 
force ; but  other  appearances  presented  themselves.  For,  if  the  crystalline  mass  was 
revolving  when  the  magnetic  force  was  excited,  it  suddenly  stopped,  and  was  caught 
in  a position  which  might,  as  was  found  by  experience,  be  any  position  ; but  if  the 
greatest  length  was  out  of  the  axial  or  equatorial  position,  the  arrest  was  followed  by 
a revulsive  motion  on  the  discontinuance  of  the  electric  current  (2315.).  This  revul- 
sive motion  was  never  great,  but  was  most  when  the  length  of  the  mass  formed  about 
an  angle  of  45°  with  the  axis  of  the  magnetic  field. 

2514.  On  further  examination  it  appeared  that  this  arresting  and  revulsive  effect 
was  precisely  the  same  in  kind  as  that  observed  on  a former  occasion  with  copper  and 
other  metals  (2309.),  and  due  to  the  same  cause,  namely,  the  production  of  circular 
electric  currents  in  the  metal  under  the  inductive  force  of  the  magnet.  Now,  the 
reason  appeared  why,  in  the  former  case,  the  crystals  of  antimony  did  not  oscillate 
(2512.)  ; and  why,  also,  they  went  up  to  their  position  of  rest  with  a dead  set ; for  the 
currents  produced  by  the  motion  are  just  those  which  tend  to  stop  the  motion 
(2329.)*  ; and  though  the  magnecrystallic  force  was  sufficient  to  make  the  crystal 
move  and  point,  yet  the  very  motion  so  produced  generated  the  current  which  reacted 
upon  the  tendency  to  motion,  and  so  caused  the  mass  to  advance  towards  its  position 
of  rest  as  if  it  moved  in  a thick  fluid. 

2515.  Having  this  additional  knowledge  respecting  the  arrest  and  revulsion  of  the 
antimony  (effects  dependent  upon  its  superior  conducting  power,  in  this  compact 
crystalline  state,  as  compared  with  bismuth),  one  has  no  difficulty  in  identifying  the 
magnecrystallic  force  of  this  metal  with  that  of  the  former,  and  the  correspondence 
of  the  results  in  all  essential  characters  and  particulars.  In  most  of  the  pieces  of 
crystals  of  antimony  the  force  seemed  less  than  in  bismuth,  but  the  fact  may  not 
really  be  so,  for  the  inductive  current  action  just  described,  tends  to  hide  the  mag- 
necrystallic phenomena. 

2516.  Different  pieces  of  antimony  also  seem  to  differ  from  each  other  in  their 
setting  force,  and  also  in  their  tendency  to  exhibit  revulsive  effects ; but  these  dif- 
ferences are  either  only  apparent,  or  may  easily  be  explained.  The  arresting  and 
revulsive  action  depends  much  upon  the  continuity  of  the  mass,  so  that  one  large 
piece  shows  it  much  better  than  several  small  pieces,  and  these  again  better  than  a 

* Any  one  who  wishes  to  form  a sufScient  idea  of  the  arresting  powers  of  these  induced  currents,  should 
take  a lump  of  solid  copper,  approaching  to  the  cubical  or  globular  form,  weighing  from  a quarter  to  half  a 
pound ; should  suspend  it  by  a long  thread,  give  it  a rapid  rotation,  and  then  introduce  it,  spinning,  into  the 
magnetic  field  of  the  electro-magnet ; he  will  find  its  motion  to  be  instantly  stopped  ; and  if  he  further  tries  to 
spin  it,  whilst  in  the  field,  will  find  it  impossible  to  do  so. 


PLATES  OF  ANTIMONY — PECULIAR  EFFECTS. 


15 


powdered  substance.  Even  the  revulsive  action  of  copper  may  be  entirely  destroyed 
by  reducing  the  single  lump  to  filings.  It  is  easy  to  perceive,  therefore,  that  of  two 
groups  of  antimony  crystals,  each  symmetrically  disposed  within  itself,  the  one  may 
have  larger  crystals  well  connected  together,  as  regards  the  induction  of  currents 
through  the  whole  mass,  and  the  other  smaller  crystals  less  favourably  united. 
These  would  present  very  different  appearances,  as  regards  the  arrest  of  motion  and 
succeeding  revulsive  action  ; and  further,  on  that  very  account,  would  differ  in  their 
readiness  to  present  the  magnecrystallic  phenomena,  though  they  might  possess  pre- 
cisely equal  degrees  of  that  force. 

251/.  On  proceeding  to  experiment  with  plates  of  antimony,  further  illustrations 
of  the  effects  resulting  from  the  causes  just  described  were  obtained,  with  abundant 
accompanying  evidence  of  the  existence  of  the  magnecrystallic  condition  in  the  metal. 
The  plates  were  selected  from  broken  masses,  as  with  bismuth  (2480.).  Some  were 
soon  found  which  acted  simply,  instantly,  and  well;  their  large  surfaces  were  bright 
cleavage  planes.  When  suspended  by  any  part  of  the  edge,  these  planes  faced  towards 
the  magnetic  poles ; and  the  plate  oscillated  on  each  side  of  its  final  position,  gradually- 
acquiring  its  state  of  rest. 

2518.  When  these  plates  were  suspended  with  their  planes  horizontal,  they  had  no 
pov/er  of  pointing  in  the  magnetic  field.  When  they  were  inclined,  the  points  which 
were  most  depressed  below  and  raised  above  the  horizontal  plane,  were  those  which 
took  up  their  plaees  nearest  the  magnetic  poles  (2482.). 

2519.  When  several  plates  were  arranged  together  into  a consistent  bundle  (2483.), 
the  diamagnetic  effect  was  removed,  and  the  magnecrystallic  oscillation  and  pointing 
became  very  ready  and  characteristic. 

2520.  Thus  it  is  evident  that,  in  all  these  cases,  there  was  a line  of  magnecrystallic 
force  perpendicular  to  the  planes  of  the  plates,  and  perfectly  consistent  in  its  position 
and  action  with  the  force  before  found  in  the  solid  crystals  of  antimony. 

2521.  But  another  plate  of  antimony  was  now  selected,  which  had  every  appear- 
ance of  being  able  to  present  all  the  phenomena  of  the  former  plates  ; and  yet,  when 
hung  up  by  its  edge,  it  showed  no  signs  of  magnecrystallic  results  ; for  it  first  ad- 
vanced a little  (23 1 0.),  then  was  arrested  and  kept  in  its  place,  and  if  standing  between 
the  axial  and  equatorial  positions,  was  revulsed  when  the  battery  current  was  inter- 
rupted, exhibiting  effects  equal  to  those  of  copper  (2315.).  Many  other  plates  were 
tried  with  precisely  the  same  result. 

2522.  When  this  plate  (2521.)  was  placed  in  the  field  of  intense  power  between 
two  conical  magnetic  poles,  it  exhibited  the  same  phenomena  ; but  notwithstanding 
the  arresting  action,  it  moved  slowly  until  it  stood  in  the  equatorial  position ; a 
result  which  was  probably  due  to  the  exertion  of  both  magnecrystallic  and  diamag- 
netic force.  When  the  plate  was  suspended  with  its  planes  horizontal,  the  arresting 
and  revulsive  actions  were  gone  ; for  the  induced  currents  which  before  caused  them 
could  not  now  exist  in  the  necessary  vertical  plane ; further,  it  had  no  setting  power. 


16  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

which  showed  that  there  was  no  axis  of  magnecrystallic  force  in  the  length  or  breadth 
of  the  plates. 

2523.  Other  plates  were  then  found  able  to  produce  mixed  effects,  and  those  in 
different  degrees.  Thus,  some,  like  the  first,  vibrated  freely,  pointed  well,  and  pre- 
sented no  indication  of  the  arrest  and  revulsive  phenomena.  Others  vibrated  slug- 
gishly, set  well,  and  showed  a tendency  to  be  arrested.  Others  pointed  well,  going 
up  to  their  place  with  a dead  set,  but  moving  as  if  in  a fluid  ;.or,  if  the  magnetic  force 
were  taken  off  before  the  piece  had  settled,  it  was  revulsed  feebly : and  others  were 
caught  at  once,  did  not  set  (within  the  time  of  my  observation),  and  were  strongly 
revulsed. 

2524.  Finally,  a careful  investigation,  carried  on  by  means  both  of  the  horse-shoe 
(2485.)  and  the  great  electro-magnet  (2247.),  made  the  cause  of  these  differences  in 
the  effects  apparent. 

2525.  It  may  be  observed,  in  the  first  place,  that  sometimes  a plate  of  antimony 
being  selected  (2517.),  having  planes  very  bright  and  perfect  in  their  appearance, 
and,  therefore,  giving  reason  to  think  that  it  may  point  well  in  the  magnetic  field, 
when  submitted  to  the  horse-shoe  magnet  does  not  do  so ; but  points  obliquely, 
feebly,  and  perhaps  in  two  undiametral  positions.  This  is,  I have  no  doubt,  because 
the  crystallization  is  complicated  and  confused.  Such  a plate,  if  it  be  sufficiently 
broad  and  long  (i.  e.  not  less  than  a quarter  or  one-third  of  an  inch),  when  submitted 
to  the  electro-magnet,  will  show  the  arresting  (2310.)  and  revulsive  (2315.)  action 
well. 

2526.  In  the  next  place,  we  have  to  remember  that,  for  the  development  of  the 
induced  currents  that  cause  the  arresting  and  revulsive  action,  the  plate  must  have 
certain  sufficient  dimensions  in  a vertical  plane  (2329.).  The  currents  occur  in  the 
mass  and  not  round  the  separate  particles  (2329.),  and  the  resultant  of  the  magnetic 
lines  of  force  passing  through  the  substance,  is  the  axis  round  which  these  currents 
are  produced.  Hence  the  reason  why  the  effect  does  not  occur  with  plates  suspended 
in  the  horizontal  position,  which  yet  produce  it  well  in  the  vertical  position  ; a result 
which  a disc  half  an  inch  in  diameter  of  thin  foil  or  plate,  being  copper,  silver,  gold, 
tin,  or  almost  any  malleable  metal  will  show;  though  the  best  conductors  are  the 
fittest  for  the  purpose.  Now  this  condition  is  of  no  consequence  in  respect  of  mag- 
necrystaUic  action,  and  a narrow  plate  has  as  much  force  as  a broad  one,  having  the 
same  mass.  The  first  plate  that  I happened  to  select  (2517.)  was  well  crystallized, 
thick  and  narrow  ; hence  it  was  favourable  for  magnecrystallic  action,  unfavourable 
to  the  arresting  and  revulsive  action,  and  showed  no  signs,  comparatively,  of  the 
latter. 

2527.  When  a broad  and  well-crystallized  plate  is  obtained,  then  both  sets  of 
effects  appear : thus,  if  the  plate  is  revolving  when  the  magnetic  force  is  brought 
into  action,  it  quickens  its  velocity  for  an  instant,  then  is  stopped  ; and  if  the  mag- 
netic force  is  at  once  taken  off,  it  is  revulsed,  exactly  as  a piece  of  copper  would  be 


MAGNECRYSTALLIC  CONDITION  OF  ANTIMONY — OF  ARSENIC. 


17 


(2315.).  But  if  the  magnetic  force  be  continued,  it  will  then  be  perceived  that  the 
stop  is  only  apparent ; for  the  plate  moves,  though  with  a greatly  reduced  velocity, 
and  continues  to  move  until  it  has  taken  up  its  magnecrystallic  position.  It  moves  as 
if  in  a thick  fluid.  Hence  the  magnecrystallic  force  is  there  and  produces  its  full  effect; 
and  the  reason  why  the  appearances  have  changed  is,  that  the  very  motion  which  the 
force  tends  to  give,  and  does  give  to  the  mass,  causes  those  magneto-electric  cur- 
rents (2329.)  which  by  their  mutual  action  with  the  magnet  tends  to  stop  the  motion  ; 
and  therefore  its  slowness  and  the  final  dead  set  (2512.  2523.). 

2528.  A magnet  which  is  weaker  (as  the  horse-shoe  instrument  described  (2485.)) 
produces  the  currents  by  induction  in  a much  weaker  degree,  and  yet  manifests  the 
magnecrystallic  power  well ; hence  it  is  more  favourable,  under  certain  circum- 
stances, for  such  investigations ; as  it  helps  to  distinguish  the  one  effect  from  the 
other. 

2529.  It  will  readily  be  seen  that  plates,  whether  of  the  same  metal  or  of  different 
metals,  cannot,  even  roughly,  be  compared  with  each  other  as  to  magnecrystallic 
force  by  their  vibrations  ; for  under  the  influence  of  these  induced  currents,  plates 
of  the  same  magnecrystallic  force  oscillate  in  very  different  manners.  I took  a plate, 
and  by  cement  (2458.)  attached  selected  paper  to  its  faces,  and  then  observed  how 
it  acted  in  the  magnetic  field  ; it  set  slowly,  and  it  showed  the  arresting  and  revulsive 
effects  (2521.).  I then  pressed  it  in  a mortar,  so  as  to  break  it  up  into  many  parts, 
which  still  kept  their  place  ; and  now  it  set  more  freely  and  quickly,  and  showed 
very  little  of  the  revulsing  action. 

2530.  Though  the  indication  by  vibration  is  thus  uncertain,  the  torsion  force  still 
remains  to  us,  I believe,  a very  accurate  indication  of  the  strength  of  the  set  (2500.) ; 
and,  therefore,  of  the  degree  of  the  magnecrystallic  force  ; and  though  the  suspending 
silk  fibre  may  give  way  a little,  a glass  thread,  according  to  Ritchie’s  suggestion, 
would  answer  perfectly. 

2531.  Antimony  must  be  a good  conductor  of  electricity  in  the  direction  of  the 
plates  of  the  crystals,  or  it  would  not  give,  so  freely,  these  indications  of  revulsive 
action.  The  groups  of  crystals  of  antimony  (2508.)  showed  the  effect  in  such  a de- 
gree, as  to  make  me  think  that  the  constituent  cubes  possessed  the  power  nearly 
equally  in  all  directions.  A piece  of  finely  crystallized  or  granular  antimony  does 
not,  however,  show  it  in  the  same  proportion ; from  which  it  would  seem  as  if  an 
effect  equivalent  in  some  degree  to  that  of  division  occurs,  either  at  the  meeting  of 
two  incongruous  crystals,  or  between  the  contiguous  plates  of  the  crystals,  and  affects 
the  conducting  power  in  these  directions. 

^ iii.  Crystalline  Polarity  of  Arsenic. 

2532.  A mass  of  the  metal  arsenic  exhibiting  crystalline  structure  (2480.),  was 
broken  up,  and  several  plates  selected  from  the  fragments,  having  good  cleavage 
plane  surfaces,  about  0 3 of  an  inch  in  length,  0*1  inch  in  width,  and  0‘03  in  thick- 

MDCCCXLIX.  D 


18  DR.  FARi^DAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

ness.  These,  when  suspended  opposite  one  conical  pole,  proved  to  be  perfectly  dia- 
magnetic ; and  when  before  it  or  between  two  poles  strongly  magnecrystallic.  I have 
a pair  of  flat-faced  poles  with  screw-holes  in  the  centre  of  the  faces,  and  these  so 
much  weaken  the  intensity  of  the  lines  of  magnetic  force  about  the  middle  of  the 
field,  when  the  faces  are  within  half  an  inch  of  each  other,  that  a cylinder  of  gra- 
nular bismuth  0'3  in  length  sets  axially,  or  from  pole  to  pole  (2384.).  But  with 
the  plates  of  arsenic  between  the  same  poles  there  was  no  tendency  of  this  kind ; so 
much  was  the  magnecrystallic  force  predominant  over  the  diamagnetic  force  of  the 
substance. 

2533.  When  the  plates  of  arsenic  were  suspended  with  their  planes  horizontal, 
then  they  did  not  point  at  all  between  the  flat-faced  poles.  Any  inclination  of  the 
planes  to  the  horizontal  line  produced  pointing,  with  more  or  less  force  as  the  planes 
approached  more  or  less  to  the  vertical  position,  exactly  in  the  manner  already  de- 
scribed in  relation  to  bismuth  and  antimony  (2482.  2518.). 

2534.  Thus,  arsenic  with  bismuth  and  antimony  are  found  to  possess  the  magne- 
crystallic force  or  condition. 


Royal  Institution, 
September  23,  1848. 


[ 19  ] 


II.  Experimental  Researches  in  Electricity. — Twenty-second  Series  {continued). 

By  Michael  Faraday,  Esq.,  D.C.L.,  F.R.S.,  Fullerian  Prof.  Chem.  Royal  Insti- 
tution, Foreign  Associate  of  the  Acad.  Sciences,  Paris,  Ord.  Boruss.  Pour  le  Mdrite, 
Eq.,  Memh.  Royal  and  Imp.  Acadd.  of  Sciences,  Petersburgh,  Florence,  Copenhagen, 
Berlin,  Gottingen,  Modena,  Stockholm,  Munich,  Bruxelles,  Vienna,  Bologna,  8fc.  Sfc. 

' Received  October  31, — Read  December  7,  1848. 


§ 28.  On  the  crystalline  polarity  of  bismuth  and  other  bodies,  and  on  its  relation  to 
the  magnetic  and  electric  form  of  force  {continued). 

^ iv.  Crystalline  condition  of  various  bodies.  ^ v.  Nature  of  the  magnecrystallic 
force,  and  general  observations. 

^ iv.  Crystalline  condition  of  various  bodies. 

2535.  Zinc. — Plates  of  zinc  broken  out  of  crystallized  masses  gave  irregular 
indications,  and,  being  magnetic  from  the  impurity  in  them,  the  effects  might  be  due 
entirely  to  that  circumstance.  Pure  zinc  was  thrown  down  electro-chemically  on 
platina  from  solutions  of  the  chloride  and  the  sulphate.  The  former  occurred  in 
ramifying  dendritic  associations  of  small  crystal;  the  latter  in  a compact  close  form. 
Both  were  free  from  magnetic  action  and  freely  diamagnetic,  but  neither  showed 
any  trace  of  the  magnecrystallic  action. 

2536.  Titanium*. — Some  good  crystals  of  titanium  obtained  from  the  bottom  of 
an  iron  furnace,  were  cleansed  by  the  alternate  action  of  acids  and  fluxes  until  as 
clear  from  iron  as  I could  procure  them.  They  were  bright,  well-formed  and  mag- 
netic (2371),  and  contained  iron,  I think,  diffused  through  their  whole  mass,  for 
nitro-muriatic  acid,  by  long  boiling,  continually  removed  titanium  and  iron  from 
them.  These  crystals  had  a certain  magnetic  property  which  I am  inclined  to  refer 
to  their  crystalline  condition.  When  between  the  poles  of  the  electro-magnet,  they 
set ; and  when  the  electric  current  was  discontinued,  they  still  set  between  the  poles 
of  the  enfeebled  magnet  as  they  did  before.  If  left  to  itself  a crystal  always  took  the 
same  position,  showing  that  it  was  constantly  rendered  magnetic  in  the  same  direc- 
tion. But  if  a crystal  was  placed  and  kept  in  another  position  between  the  magnetic 
poles  whilst  the  electric  current  was  on,  and  afterwards  the  current  suspended,  and 
then  the  crystal  set  free,  it  pointed  between  the  poles  of  the  enfeebled  magnet  in  this 
new  direction  ; showing  that  the  magnetism  was  in  a different  direction  in  the  body 

* For  these  and  many  other  crystals  I am  indebted  to  the  kindness  of  Sir  Henry  T.  De  la  Beche  and 
Mr.  Tennant. 

D 2 


20  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


of  the  crystal  to  that  which  it  had  before.  If  now  the  magnet  were  reinvigorated 
by  the  electric  current,  the  crystal  instantly  spun  round  and  took  a magnetic  state 
in  the  first  or  original  direction.  The  crystals  could  in  fact  become  magnetized  in 
any  direction,  but  there  was  one  direction  in  which  they  could  be  magnetized  with  a 
facility  and  force  greater  than  in  any  other.  From  the  appearances  I am  inclined  to 
refer  this  to  the  crystalline  condition,  but  it  may  be  due  to  an  irregular  diffusion  of 
iron  in  the  masses  of  titanium.  The  crystals  were  too  small  for  me  to  make  out  the 
point  clearly. 

2537.  Copper. — I selected  some  good  crystals  of  native  copper,  and,  having  care- 
fully separated  them  from  the  mass,  examined  them  in  respect  of  their  magnecrystallic 
force.  At  the  horse-shoe  magnet  (2486.)  they  gave  no  signs  of  such  power,  what- 
ever the  direction  in  which  they  were  suspended,  but  stood  in  any  position ; and  any 
degree  of  torsion,  however  small,  applied  at  the  upper  extremity  of  the  suspending 
filament  was  obeyed  at  once,  and  to  the  full  extent,  by  the  crystal  beneath.  When 
subjected  to  the  electro-magnet,  the  phenomena  of  arrest  and  revulsion  were  produced 
(2513.  2310.),  as  was  to  be  expected.  Tf  after  the  arrest  the  magnetic  force  were 
continued,  there  was  no  slow  advance  of  the  crystal  up  to  a distinct  pointing  position 
(2512.)  ; it  stood  perfectly  still  in  any  position.  So  there  is  no  evidence  of  magne- 
crystallic action  in  this  case. 

2538.  Tin. — 1 selected  from  block  and  grain  tin  some  pieces  which  appeared,  by 
their  external  forms  and  the  surface  produced  under  the  action  of  acids,  to  have  a 
regular  crystalline  structure  internally ; and,  cutting  off  portions,  carefully  submitted 
them  to  the  power  of  the  magnets,  but  there  was  no  appearance  of  any  magnecrystallic 
phenomena.  Indications  of  the  arresting  and  revulsive  actions  were  presented,  and 
also  of  diamagnetic  force,  but  nothing  else.  I also  examined  some  crystals  of  tin 
obtained  by  electro-chemical  deposition.  They  were  pure  and  diamagnetic  : they 
were  arrested  and  revulsed,  but  they  showed  no  signs  of  magnecrystallic  action. 

2539.  Lead. — Lead  was  crystallized  by  fusion,  partial  solidification,  and  pouring 
off  (2457.),  and  some  very  fair  crystals,  having  the  general  form  of  octohedra, 
obtained.  Observed  at  the  magnets,  these  were  arrested  and  revulsed  feebly,  but 
presented  no  magnecrystallic  phenomena.  Some  fine  crystalline  plates  of  lead  ob- 
tained electro-chemically  from  the  decomposition  of  the  acetate  by  zinc,  were  sub- 
mitted to  the  magnet : they  were  pure,  diamagnetic,  and  were  arrested  and  revulsed, 
but  presented  no  appearance  of  magnecrystallic  action. 

2540.  Gold. — Three  fine  large  crystals  of  gold  were  examined.  They  were 
diamagnetic,  and  easily  arrested  (2310.  2340.) ; the  revulsion  did  not  take  place, 
because  of  their  octohedral  or  orbicular  form.  They  presented  no  magnecrystallic 
indications. 

2541.  Tellurium. — Two  fractured  pieces  of  this  substance,  presenting  large  and 
parallel  planes  of  cleavage,  were  examined : both  pointed,  and  the  greatest  length 
was  across  the  axial  line  between  flat-faced  poles  (2463.).  I think  the  effects  w^ere 


MAGNECRYSTALLIC  CONDITION  OF  SULPHATE  OF  IRON,  ETC. 


21 


in  part,  if  not  altogether,  due  to  the  magnecrystallic  state  of  the  substance  ; but  I 
do  not  think  the  evidence  was  quite  conclusive. 

2542.  Iridium  and  Osmium  alloy. — The  native  grains  of  iridium  and  osmium  are 
often  flat,  presenting  two  planes  looking  like  crystal  planes,  which  are  parallel  to 
each  other  even  when  the  grains  are  thick.  Some  of  the  largest  and  most  crystalline 
were  selected,  and,  after  ignition  with  flux  and  digestion  in  nitromuriatic  acid,  were 
examined  at  the  magnet.  Some  were  more  magnetic  than  others,  being  attracted  ; 
others  were  very  little  magnetic  : the  latter  were  selected  and  examined  more  carefully. 
These  all  pointed  with  great  readiness  and  force,  comparatively  speaking ; for  they 
were  not  above  one-fifteenth  of  an  inch  long,  and  yet  they  set  freely  when  the  mag- 
netic poles  were  three  or  four  inches  apart.  The  faces  of  the  crystalline  particles 
were  always  towards  the  poles,  and  their  length  consequently  not  in  but  across  the 
axial  line  ; and  this  was  true  whether  the  distance  between  the  poles  was  small  or 
great,  or  whether  flat-faced  or  conical  poles  were  used.  I believe  they  were  magne- 
crystallic. 

2543.  Fusible  metal. — Crystals  of  fusible  metal  (24570  pointed,  but  the  crystals, 
which  were  apparently  quadrangular  plates  or  prisms,  were  not  good,  and  the 
evidence  not  clear  and  distinct. 

2544.  Wires. — I thought  it  possible  that  thin  wires,  which  by  the  action  of  acids 
exhibited  fibrous  arrangements,  might  have  their  particles  in  a state  approaching  to 
the  crystalline  condition,  and  therefore  submitted  bundles  of  platinum,  copper,  and 
tin  wire  to  the  action  of  the  magnet ; but  no  indications  of  magnecrystallic  action 
appeared. 

2545.  I submitted  several  metallic  compounds  to  the  power  of  the  magnet,  applied 
so  as  to  develope  any  indication  of  the  magnecrystallic  phenomena.  Galena,  native 
cinnabar,  oxide  of  tin,  sulphuret  of  tin,  native  red  oxide  of  copper,  Brookite  or  oxide 
of  titanium,  iron  pyrites,  and  also  diamond,  fluor  spar,  rock-salt  and  boracite,  being 
all  well-crystallized  and  diamagnetic,  presented  no  evidence  of  the  magnecrystallic 
force.  Native  and  well -crystallized  sulphuret  of  copper,  sulphuret  of  zinc,  cobalt 
glance  and  leucites  were  magnetic.  Arsenical  iron,  specular  iron  and  magnetic  oxide 
of  iron  were  still  more  so.  I could  not  in  any  of  them  distinguish  any  magnetic 
results  due  to  crystallization. 

2546.  On  examining  magnetic  salts,  several  of  them  presented  very  striking  mag- 
necrystallic phenomena.  Thus,  with  sulphate  of  iron,  the  first  crystal  which  J 
employed  was  suspended  with  the  magnecrystallic  axis  vertical,  and  it  presented  no 
particular  appearances ; only  the  longest  horizontal  direction  went  into  the  magnetic- 
axis  pointing  feebly.  But  on  turning  the  piece  90°  (2470.),  instantly  it  pointed  with 
much  force,  and  the  greatest  length  went  equatorially.  The  crystal  was  compounded 
of  superposed  flat  crystals  or  plates,  and  the  magnecrystallic  axis  went  directly  across 
these  ; it  was  easy,  therefore,  after  one  or  two  experiments,  to  tell  beforehand  how  the 
crystal  should  be  suspended,  and  how  it  would  point.  Whether  the  crystals  were 


22  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

long,  or  oblique,  or  irregular,  still  the  magnecrystallic  force  predominated  and  deter- 
mined the  position  of  the  crystal,  and  this  happened  whether  pointed  or  flat  poles 
were  used,  and  whether  they  were  near  together  or  far  asunder.  The  magnecrystallic 
axis  is  perpendicular,  or  nearly  so,  to  two  of  the  sides  of  the  rhomboidal  prism.  I 
have  some  small  prismatic  crystals  of  which  the  length  is  nearly  three  times  the  width 
of  the  prism  ; but  when  both  the  length  and  the  magnecrystallic  axis  are  horizontal, 
no  power  of  the  magnet,  or  shape,  or  position  of  the  poles,  will  cause  the  length  to 
take  the  axial  direction,  for  that  is  constantly  retained  by  the  magnecrystallic  axis, 
so  greatly  does  it  predominate  in  power  over  the  mere  magnetic  force  of  the  crystal. 
Yet  this  latter  is  so  great  as  at  times  to  pull  the  suspending  fibre  asunder  when  the 
crystal  is  above  the  poles  (2615.). 

2547.  Sulphate  of  nichel. — When  a crystal  of  sulphate  of  nickel  was  suspended  in 
the  magnetic  field,  its  length  set  axially.  This  might  be  due,  either  to  mere  mag- 
netic force,  or  partly  to  magnecrystallic  force.  Therefore  I cut  a cube  out  of  the 
crystal,  two  faces  of  which  were  perpendicular  to  the  length  of  the  original  prism. 
This  cube  pointed  well  in  the  magnetic  field,  and  the  line  coincident  with  the  axis  of 
the  prism  was  that  which  pointed  axially,  and  represented  the  magnecrystallic  axis. 
Even  when  the  cube  was  reduced  in  this  direction  and  converted  into  a square  plate 
whose  thickness  coincided  with  the  magnecrystallic  axis,  it  pointed  as  well  as  before, 
though  the  shortest  dimensions  of  the  piece  was  now  axial. 

2548.  The  persulphate  of  ammonia  and  iron,  and  the  sulphate  of  manganese,  did  not 
give  any  indication  of  magnecrystallic  phenomena  ; the  sulphate  of  ammonia  and 
manganese  I think  did,  but  the  crystals  were  not  good.  The  sulphate  of  potassa  and 
nickel  is  magnecrystallic.  All  three  salts  were  magnetic. 

2549.  Thus  it  seems  that  other  bodies  besides  bismuth,  antimony  and  arsenic, 
present  magnecrystallic  effects.  Amongst  these  are  the  alloy  of  iridium  and  osmium, 
probably  tellurium  and  titanium,  and  certainly  the  sulphates  of  iron  and  nickel. 
Before  leaving  this  part  of  the  subject,  I may  remark  that  this  property  has  probably 
led  me  into  error  at  times  on  a former  occasion  (2290.).  A mistake  with  arsenic 
(2383.)  might  very  easily  arise  from  this  cause. 

^ V.  On  the  nature  of  the  magnecrystallic  force,  and  general  observations. 

2550.  The  magnecrystallic  force  appears  to  be  very  clearly  distinguished  from 
either  the  magnetic  or  diamagnetic  forces,  in  that  it  causes  neither  approach  nor 
recession ; consisting  not  in  attraction  or  repulsion,  but  in  its  giving  a certain  de- 
terminate position  to  the  mass  under  its  influence,  so  that  a given  line  in  relation  to 
the  mass  is  brought  by  it  into  a given  relation  with  the  direction  of  the  external 
magnetic  power. 

2551.  I thought  it  right  very  carefully  to  examine  and  prove  the  conclusion,  that 
there  was  no  connection  of  the  force  with  either  attractive  or  repulsive  influences. 
For  this  purpose  I constructed  a torsion-balance,  with  a bifilar  suspension  of  cocoon 


MAGNECRYSTALLIC  FORCE — NOT  ATTRACTIVE  NOR  REPULSIVE. 


23 


silkj  consisting  of  two  bundles  of  seven  filaments  each^  four  inches  long  and  one- 
twelfth  of  an  inch  apart ; and  suspended  a crystal  of  bismuth  (2457.)  ffom  one  end  of 
the  lever,  so  that  it  might  be  fixed  and  retained  in  any  position.  This  balance  was 
protected  by  a glass  case,  outside  of  which  the  conical  terminal  of  one  pole  of  the 
great  electro-magnet  (2247.)  was  adjusted,  so  as  to  be  horizontal,  at  right  angles  to 
the  lever  of  the  torsion-balance,  and  in  such  a position  that  the  bismuth  crystal  was 
in  the  prolongation  of  the  axis  of  the  pole,  and  about  half  an  inch  from  its  extremity 
when  all  was  at  rest.  The  other  pole,  four  inches  off,  was  left  large  so  that  the  lines 
of  magnetic  force  should  diverge,  as  it  were,  and  rapidly  diminish  in  strength  from 
the  end  of  the  conical  pole.  The  object  was  to  observe  the  degree  of  repulsion  ex- 
erted by  the  magnet  on  the  bismuth,  as  a diamagnetic  body,  either  by  the  distance 
to  which  it  was  repelled,  or  by  the  torsion  required  to  bring  it  back  to  its  first  posi- 
tion ; and  to  do  this  with  the  bismuth,  having  its  magnecrystallic  axis  at  one  time 
axial  or  parallel  to  the  lines  of  magnetic  force,  at  another  equatorial,  observing  whether 
any  difference  was  produced. 

2552.  The  crystal  was  therefore  placed  with  its  magnecrystallic  axis  first  parallel 
to  the  lines  of  magnetic  force,  and  then  turned  four  times  in  succession  90°  in  a 
horizontal  plane,  so  as  to  observe  it  under  all  positions  of  the  magnecrystallic  axis ; 
but  in  no  case  could  any  difference  in  the  amount  of  the  repulsion  be  observed.  In 
other  experiments  the  axis  was  placed  oblique,  but  still  with  the  same  result.  If 
there  be  therefore  any  difference  it  must  be  exceedingly  small. 

2553.  A corresponding  experiment  was  made,  hanging  the  crystal  as  a pendulum 
by  a bifilar  suspension  of  cocoon  silk  thirty  feet  in  length,  with  the  same  result. 

2554.  Another  very  striking  series  of  proofs  that  the  effect  is  not  due  to  attraction 
or  repulsion,  was  obtained  in  the  following  manner.  A skein  of  fifteen  filaments  of 
cocoon  silk,  about  fourteen  inches  long,  was  made  fast  above,  and  then  a weight  of 
an  ounce  or  more  hung  to  the  lower  end ; the  middle  of  this  skein  was  about  the 
middle  of  the  magnetic  field  of  the  electro-magnet,  and  the  square  weight  below 
rested  against  the  side  of  a block  of  wood,  so  as  to  give  a steady,  silken,  vertical  axis, 
without  swing  or  revolution.  A small  strip  of  card,  about  half  an  inch  long,  and 
the  tenth  of  an  inch  broad,  was  fastened  across  the  middle  of  this  axis  by  cement ; 
and  then  a small  prismatic  crystal  of  sulphate  of  iron  about  0‘3  of  an  inch  long,  and 
0*1  in  thickness,  was  attached  to  the  card,  so  that  the  length,  and  also  the  magne- 
crystallic axis,  were  in  the  horizontal  plane  ; all  the  length  was  on  one  side  of  the 
silken  axis,  so  that  as  the  crystal  swung  round,  the  length  was  radius  to  the  circle 
described,  and  the  magnecrystallic  axis  parallel  to  the  tangent. 

2555.  This  crystal  took  a position  of  rest  due  to  the  torsion  force  of  the  suspending 
skein  of  silk  ; and  the  position  could  be  made  any  one  that  was  desired,  by  turning 
the  weight  below.  The  torsion  force  was  such,  that,  when  the  crystal  was  made  to 
vibrate  on  its  silken  axis,  forty  complete  (or  to  and  fro)  vibrations  were  performed 
in  a minute. 


24  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

2556.  When  the  crystal  was  made  to  stand  between  the  flat-  Fig.  4. 

faced  poles  (2463.)  obliquely,  as  in  fi^.  4,  the  moment  the  magnet 
was  excited  it  moved,  tending  to  stand  with  its  length  equatorial 
or  its  magnecrystallic  axis  parallel  to  the  lines  of  magnetic  force. 

When  the  N pole  was  removed,  and  the  experiment  repeated,  the 
same  effect  took  place,  but  not  as  strongly  as  before ; and  when,  finally,  the  pole  S 
was  brought  as  near  to  the  crystal  as  it  could  be,  without  touching  it,  the  same  result 
occurred,  and  with  more  strength  than  in  the  last  case. 

2557.  In  the  two  latter  experiments,  therefore,  the  crystal  of  sulphate  of  iron,  though 
a magnetic  body  and  strongly  attracted  by  such  a magnet  as  that  used,  actually  re- 
ceded from  the  pole  of  the  magnet  under  the  infiuence  of  the  magnecrystallic  condition. 

2558.  If  the  pole  S be  removed  and  that  marked  N be  retained  for  action  on 
the  crystal,  then  the  latter  approaches  the  pole,  urged  by  both  the  magnetic  and 
magnecrystallic  forces  ; but  if  the  crystal  be  revolved  90°  to  the  left,  or  180°  to  the 
right,  round  the  silken  axis,  so  as  to  come  into  the  contrary  or  opposite  position, 
then  this  pole  repels  or  rather  causes  the  removal  to  a distance  of  the  crystal,  just  as 
the  former  did.  The  experiment  requires  care,  and  I find  that  conical  poles  are  not 
good  ; but  Avith  attention  I could  obtain  the  results  with  the  uttnost  readiness. 

2559.  The  sulphate  of  iron  was  then  replaced  by  a crystalline  plate  (2480.)  of 
bismuth,  placed  as  before  on  one  side  of  the  silk  suspender,  and  with  its  magnecry- 
stallic axis  horizontal.  Making  the  position  the  same  as  that  which  the  crystal  had 
in  relation  to  the  N pole  in  the  former  experiment  (2556.),  so  that  to  place  its  axis 
parallel  to  the  lines  of  magnetic  force  it  must  approach  this  magnetic  pole,  and  then 
throwing  the  magnet  into  an  active  state,  the  bismuth  moved  accordingly,  and  did 
approach  the  pole,  against  its  diamagnetic  tendency,  but  under  the  infiuence  of  the 
magnecrystallic  force.  The  effect  was  small  but  distinct. 

2560.  Anticipating,  for  a short  time,  the  result  of  the  reasoning  to  be  given  further 
on  (26O7.),  I will  describe  a corresponding  effect  obtained  with  the  red  ferro-prussiate 
of  potassa.  A crystal  of  this  salt  had  its  acute  linear  angles  ground  away,  so  as  to 
convert  it  into  a plate  with  faces  parallel  to  the  plane  of  the  optic  axis,  and  was  then 
made  to  replace  the  plate  of  bismuth.  Being  in  the  position  before  represented 
(2556.),  and  the  magnet  rendered  active,  it  moved,  placing  the  plane  of  the  optic  axes 
eqnatorially,  as  Plucker  describes.  When  the  pole  N was  removed  and  S brought 
up  to  the  crystal,  the  same  motion  occurred,  the  crystal  retreating  from  the  pole  ; 
and  when  S pole  was  removed  and  N brought  towards  the  crystal,  it  moved  as  be- 
fore, the  whole  body  now  approaching  towards  the  pole.  On  inclining  the  crystal 
the  other  way,  i.  e.  making  its  place  on  the  other  side  of  the  equatorial  line,  the  S 
pole  caused  it  to  approach  and  the  N pole  to  recede.  So  that  the  same  pole  seemed 
able  either  to  attract  or  repel  the  same  side  of  the  crystal ; and  either  pole  could  be 
made  to  show  this  apparent  attractive  and  repulsive  force. 

2561.  Hence  a proof  that  neither  attraction  nor  repulsion  causes  the  set,  or 


MAGNECRYSTALLIC  FORCE— ITS  NATURE  AND  PECULIARITIES. 


25 


governs  the  final  position  of  the  body,  or  of  any  of  the  bodies  whose  movements  are 
due  to  the  same  cause  (260/.). 

2562.  This  force  then  is  distinct  in  its  character  and  effects  from  the  magnetic 
and  diamagnetic  forms  of  force.  On  the  other  hand,  it  has  a most  manifest  relation 
to  the  crystalline  structure  of  the  bismuth  and  other  bodies  ; and  therefore  to  the 
molecules,  and  to  the  power  by  which  these  molecules  are  able  to  build  up  the  crys- 
talline masses.  It  appears  to  me  impossible  to  conceive  of  the  results  in  any  other 
way  than  by  a njutual  reaction  of  the  magnetic  force,  and  the  force  of  the  particles 
of  the  crystal  on  each  other : and  this  leads  the  mind  to  another  conclusion,  namely, 
that  as  far  as  they  can  act  on  each  other  they  partake  of  a like  nature ; and  brings, 
I think,  fresh  help  for  the  solution  of  that  great  problem  in  the  philosophy  of  mole- 
cular forces,  which  assumes  that  they  all  have  one  common  origin  (2146.). 

2563.  Whether  we  consider  a crystal  or  a particle  of  bismuth,  its  polarity  has  a 
very  extraordinary  character,  as  compared  with  the  polarity  of  a particle  in  the  ordi- 
nary magnetic  state,  or  when  compared  with  any  other  of  the  dual  conditions  cf 
physical  force ; for  the  opposite  poles  have  like  characters ; as  is  shown  first  of  all 
by  the  diametral  pointing  of  the  masses  (2461.),  and  also  by  the  physical  characters 
and  relations  of  crystals  generally.  As  the  molecules  lie  in  the  mass  of  a crystal, 
therefore,  they  can  in  no  way  represent,  or  be  represented  by,  the  condition  of  a 
parcel  of  iron  filings  between  the  poles  of  a magnet,  or  the  particles  of  iron  in  the 
keeper  when  in  its  place  ; for  these  have  poles  of  dijferent  names  and  quality  adhering 
together,  and  so  giving  a sort  of  structure ; whereas,  in  the  crystal,  the  mole- 
cules have  poles  of  like  nature  towards  each  other,  for,  so  to  say,  all  the  poles  are 
alike. 

2564.  As  made  manifest  by  the  phenomena,  the  magnecrystallic  force  is  a force 
acting  at  a distance;  for  the  crystal  is  moved  by  the  magnet  at  a distance  (2556. 
2574.),  and  the  crystal  also  can  move  the  magnet  at  a distance.  To  produce  the 
latter  result,  I converted  a steel  bodkin,  about  three  inches  long,  into  a magnet ; and 
then  suspended  it  perpendicularly  by  a single  cocoon  filament  four  inches  long,  from  a 
small  horizontal  rod,  which  again  was  suspended  by  its  centre  and  another  length  of 
cocoon  filament,  from  a fixed  point  of  support.  In  this  manner  the  bodkin  was  free 
to  move  on  its  own  axis,  and  could  also  describe  a circle  about  IJ  inch  in  diameter; 
and  the  latter  motion  was  not  hindered  by  any  tendency  of  the  needle  to  point  under 
the  earth’s  influence,  because  it  could  take  any  position  in  the  circle  and  yet  remain 
parallel  to  itself. 

2565.  A support  perfectly  free  from  magnetic  action  was  constructed  of  glass  rod 
and  copper  wire,  which  passing  through  the  bottom  of  the  stand,  and  being  in  the 
prolongation  of  the  upper  axis  of  motion,  was  concentric  with  the  circle  which  the 
little  magnet  could  describe ; its  height  was  such  that  it  could  sustain  a crystal  or 
any  other  substance  level  with  the  pole  at  the  lower  end  of  the  needle,  and  in  the 
centre  of  the  small  circle  in  which  the  latter  could  revolve  around  it.  By  moving 
the  lower  end  of  the  support,  the  upper  end  also  could  be  made  to  approach  to  or 

MDCCCXLIX.  E 


26  DPt.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


recede  from  the  magnet.  The  whole  was  covered  with  a glass  shade,  and  when  left 
to  become  of  uniform  temperature,  and  at  rest,  the  needle  magnet  was  found  to  take 
up  a constant  position  under  the  torsion  force  of  the  susperiding  filaments.  Further, 
any  rotation  of  the  glass  and  copper  wire  support  did  not  produce  a final  change  in 
the  position  of  the  magnet ; for  though  the  motion  of  the  air  would  carry  the  magnet 
away,  it  returned,  ultimately,  to  the  same  spot.  When  removed  from  this  spot,  the 
torsion  force  of  the  silk  susj)ension  made  the  system  oscillate;  the  time  of  a half 
oscillation,  or  a passage  in  one  direction,  w'as  about  tliree  minutes,  and  of  a whole 
oscillation  therefore  six  minutes. 

2566.  When  a crystal  bismuth  was  fixed  on  the  support  with  the  magnecrystallic 
axis  in  a horizontal  direction,  it  could  be  placed  near  the  lower  pole  of  the  magnet 
in  any  position,  and  being  then  left  for  two  or  three  hours,  or  until  by  repeated  exa- 
mination the  magnetic  pole  was  found  to  be  stationary,  the  place  of  the  latter  could 
be  examined  and  the  degree  and  direction  in  which  it  was  affected  by  the  bismuth 
ascertained.  Extreme  precaution  was  required  in  these  observations,  and  all  steel 
or  iron  things,  as  spectacles,  knives,  keys,  &c.,  had  to  be  dismissed  from  the  ob- 
server before  he  entered  the  place  of  experiment ; and  glass  candlesticks  were  used. 
The  effect  produced  was  but  small,  but  the  result  was,  that  if  the  direction  of  the 
magnecrystallic  axis  made  an  angle  of  10°,  20°,  or  30°  with  the  line  from  the  mag- 
netic pole  to  the  middle  of  the  bismuth  crystal,  then  the  pole  followed  it,  tending 
to  bring  the  two  lines  into  parallelism  ; and  this  it  did  whichever  end  of  the  magne- 
crystallic axis  was  towards  the  pole,  or  whiehever  side  it  was  inclined  to.  By 
moving  the  bismuth  at  successive  times,  the  deviation  of  the  magnetic  pole  could  be 
carried  up  to  60°. 

2567.  The  crystal  of  bismuth  therefore  is  able  to  react  upon  and  affect  the  magnet 
at  a distance. 

2568.  But  though  it  thus  take  up  the  character  of  a force  acting  at  a distance, 
still  it  is  due  to  that  power  of  the  particles  which  makes  them  cohere  in  regular  order, 
and  gives  the  mass  its  crystalline  aggregation  ; which  we  call  at  other  times  the  attrac- 
tion of  aggregation,  and  so  often  speak  of  as  acting  at  insensible  distances. 

2569.  For  the  further  explication  of  the  nature  of  this  force,  I proceeded  to  examine 
the  effect  of  heat  on  crystals  of  bismuth  when  in  the  magnetic  field.  The  crystals 
were  suspended  either  by  platina  or  fine  copper  wire,  and  heated,  sometimes  by  a 
small  spirit-lamp  flame  applied  directly,  sometimes  in  an  oil-bath  placed  between 
the  magnetic  poles ; and  though  the  upward  currents  of  air  and  fluid  were  strong  in 
these  cases,  they  were  far  too  weak  to  overcome  the  set  caused  by  magnecrystallic 
action,  and  helped  rather  to  show  when  that  action  was  weakened  or  ceased. 

2570.  When  the  temperature  was  gradually  raised  in  the  air  the  bismuth  crystal 
continued  to  point,  until  of  a sudden  it  became  indifferent  in  that  respect,  and  turned 
in  any  direction  under  the  influence  of  the  rising  currents  of  air.  Instantly  removing 
the  lamp  flame  the  bismuth  revolved  slowly  and  regularly,  as  if  there  were  no  ten- 
dency to  take  up  one  position  more  than  another,  or  no  remains  of  magnecrystallic 


MAGNECRYSTALLIC  FORCE — AFFECTED  BY  HEAT. 


27 


action ; but  in  a few  seconds,  as  the  temperature  fell,  it  resumed  its  power  of  point- 
ing; and,  apparently,  in  an  instant  and  with  full  force,  and  the  pointing  was  pre- 
cisely in  the  same  direction  as  at  first.  On  examining  the  crystal  carefully,  its  ex- 
ternal shape  and  its  cleavage  showed  that,  as  a crystal,  it  was  unchanged ; but  the 
appearance  of  a minute  globule  of  bismuth,  which  had  exuded  upon  the  surface  in 
one  place,  showed  that  the  temperature  had  been  close  upon  the  point  of  fusion. 

2571.  The  same  result  occurred  in  the  oil-bath,  except  that  as  removing  the  lamp 
from  the  oil-bath  did  not  immediately  stop  the  addition  of  heat  to  the  bismuth,  so 
more  of  the  latter  was  melted;  and  about  one-fourth  of  the  metal  appeared  as  a drop 
hanging  at  the  lower  part.  Still  the  whole  mass  lost  its  power  at  the  high  tempera- 
ture, and  the  power  was  regained  in  the  same  direction,  but  in  a less  degree  on  cool- 
ing. The  diminished  force  was  accounted  for  on  breaking  up  the  crystal ; for  the 
parts  which  had  been  liquefied  were  now  crystallized  irregularly,  and  therefore, 
though  active  at  the  beginning  of  the  experiment,  were  neutral  at  the  end. 

2572.  As  heat  has  this  effect,  the  expectation  entertained  (2502.)  of  crystallizing 
bismuth  regularly  in  the  magnetic  Jield  is  of  course  unfounded  ; for  the  metal  must 
acquire  the  solid  state,  and  be  lowered  through  several  degrees  probably,  before  it 
can  exhibit  the  magnecrystallic  phenomena.  If  heat  has  the  same  effect  on  all  bodies 
prior  to  their  liquefaction,  then,  of  course,  such  a process  can  be  applied  to  none  of 
them. 

2573.  A crystallized  piece  of  antimony  was  subjected  to  the  same  experiment,  and 
it  also  lost  its  magnecrystallic  power  below  a dull  red  heat,  and  just  as  it  was  soften- 
ing so  as  to  take  the  impression  of  the  copper  loop  in  which  it  was  hung.  On  being 
cooled  it  did  not  resume  its  former  state,  but  then  became  ordinarily  magnetic  and 
pointed.  This  I conclude  arose  from  iron  affected  by  the  flame  and  heat  of  the  spirit- 
lamp  ; for,  as  the  heat  was  high  enough  to  burn  off  part  of  the  antimony  and  make  it 
rise  in  fumes  of  oxide  of  antimony,  so  this  might  set  a certain  portion  of  iron  free  which 
the  carbon  and  hydrogen  of  the  flame  would  leave  in  a very  magnetic  state  (2608.). 

2574.  In  further  elucidation  of  the  mutual  action  of  the  bismuth  and  the  magnet, 
the  bismuth  was  suspended,  as  already  described  (2551.),  on  the  bifilar  balance,  but 
so  turned  that  its  magnecrystallic  axis,  being  horizontal,  was  not  parallel  or  perpen- 
dicular to  the  arm  of  the  lever,  but  a little  inclined,  as  in  the 
figure  (5.),  where  1 represents  the  crystal  of  bismuth  attached 
to  the  balance  arm  h,  the  axis  of  which  is  so  placed  that  the 
crystal  can  swing  through  the  various  positions  1,  2,  3,  4 ; S 
is  the  pole  of  the  magnet  separated  only  by  the  glass  of  the 
shade.  It  is  manifest  that  in  position  1 the  magnecrystallic 
axes  and  the  lines  of  magnetic  force  are  parallel  to  each  other ; 
whereas  in  the  positions  2,  3,  4,  they  are  oblique.  When  the  apparatus  was  so 
arranged  that  the  crystal  of  bismuth  rested  at  1,  the  superinduction  of  the  full  mag- 
netic force  sent  it  towards  4 ; a result  of  diamagnetic  action.  When  however  the 

E 2 


Fig.  5. 


28  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


bismuth  had  its  place  of  rest  at  2,  the  development  of  the  magnetic  force  did  not  make 
it  pass  towards  3,  in  accordance  with  the  former  result,  but  towards  1,  which  it 
usually  attained  and  often  passed,  going  a little  towards  4.  In  this  case  the  magne- 
crystallic  and  the  diamagnetic  forces  were  opposed  to  each  other,  and  the  former 
gained  the  advantage  up  to  position  1. 

2573.  But  though  the  crystal  of  bismuth  in  these  cases  moves  across  the  lines  of 
force  in  the  magnetic  field,  it  cannot  he  expected  to  do  so  in  a field  where  the  lines 
are  parallel  and  of  equal  force,  as  between  flat-faced  poles  ; the  crystal  being  re- 
strained so  as  to  move  only  parallel  to  itself ; for  under  such  circumstances  the  forces 
are  equal  in  both  directions  and  on  both  sides  of  the  mass,  and  the  only  tendency 
the  crystal  has,  in  relation  to  its  magnecrystallic  condition,  is  to  turn  round  a ver- 
tical axis  until  it  is  in  its  natural  position  in  the  magnetic  field. 


2576.  A most  important  question  next  arises  in  relation  to  the  magnecrystallic 
force,  namely,  whether  it  is  an  original  force  inherent  in  the  crystal  of  bismuth,  &c., 
or  whether  it  is  induced  under  the  magnetic  and  electric  influences.  When  a piece 
of  soft  iron  is  held  in  the  vicinity  of  a magnet  it  acquires  new  powers  and  properties  ; 
some  persons  assume  this  to  depend  upon  the  development  by  induction  of  a new  force 
in  the  iron  and  its  particles,  like  in  nature  to  that  in  the  inducing  magnet : by  others 
it  is  considered  that  the  force  originally  existed  in  the  particles  of  the  iron,  and  that 
the  inductive  action  consisted  only  in  the  arrangement  of  all  the  elementary  forces  in 
one  general  direction.  Applying  this  to  the  crystal  of  bismuth,  we  cannot  make  use 
of  the  latter  supposition  in  the  same  manner;  for  all  the  particles  are  arranged  be- 
forehand, and  it  is  that  very  arrangement  of  them  and  their  forces  which  gives  the 
bismuth  its  power.  If  the  particles  of  a substance  be  in  the  heterogeneous  condition 
possessed  by  those  of  the  iron  in  its  unmagnetic  state,  then  the  magnetic  force  may 
develope  the  magnetic,  and  also  the  diamagnetic  condition,  which  probably  is  a 
condition  of  induction ; but  it  does  not  appear  at  once,  that  it  can  develope  a state 
of  the  kind  now  under  consideration. 

2577-  That  the  particles  hold  their  own  to  a great  extent  in  all  the  results  is  mani- 
fest, by  the  consideration  that  they  have  an  inherent  power  or  force,  the  crystalline 
force,  which  is  so  unchangeable  that  no  treatment  to  which  they  can  be  subjected 
can  alter  it;  that  it  is  this  very  force  which,  placing  the  particles  in  a regular  po- 
sition in  the  mass,  enables  them  to  act  jointly  on  the  magnet  or  the  electric  current, 
and  affect  or  be  affected  by  them  ; and  that  if  the  particles  are  not  so  arranged,  but 
are  in  all  directions  in  the  mass,  then  the  sum  of  their  forces  externally  is  nothing, 
and  no  inductive  exertion  of  the  magnet  or  current  can  develope  the  slightest  trace  of 
the  phenomena. 

2578.  And  that  particles  even  before  crystallization  can  act  in  some  degree  at  a 
distance,  by  virtue  of  their  crystallizing  force,  is,  I think,  shown  by  the  following 


AIAGNECRYSTALLIC  FORCE — INDUCED  OR  INHERENT? 


29 


fact.  A jar  containing  about  a quart  of  solution  of  sulphate  of  soda,  of  such  strength 
as  to  crystallize  when  cold  by  the  touch  of  a crystal  of  the  salt  or  an  extraneous  body, 
was  left,  accidentally,  for  a week  or  more  unattended  to  and  undisturbed.  The  solution 
remained  fluid  ; but  on  the  jar  being  touched,  crystallization  took  place  throughout 
the  whole  mass  at  once,  producing  clear,  distinet,  transparent  plates,  which  were  an 
inch  or  more  in  length,  up  to  half  an  ineh  in  breadth  ; and  very  thin,  perhaps  about 
the  one-fiftieth  or  one-sixtieth  of  an  inch.  These  were  all  horizontal,  and  of  course 
parallel  to  each  other ; and  I think,  if  I remember  rightly,  had  their  length  in  the  same 
direction  ; and  they  were  alike  in  character,  and,  apparently,  in  quantity  in  every 
part  of  the  jar.  They  almost  held  the  fluid  in  its  place  when  the  jar  was  tilted  ; and 
when  the  liquid  was  poured  off  presented  a beautiful  and  uniform  assemblage  of 
crystals.  The  result  persuaded  me,  at  the  time,  that,  though  the  influence  of  a pai- 
ticle  in  solution  and  about  to  crystallize,  must  be  immediately  and  essentially  upon 
its  neighbours,  yet  that  it  could  exert  an  influence  beyond  these,  without  which  in- 
fluence, the  whole  mass  of  solution  could  hardly  have  been  brought  into  such  a uni- 
form crystallizing  state.  Whether  the  horizontality  of  the  plates  can  have  any  rela- 
tion to  the  almost  vertical  lines  of  magnetic  force,  which  from  the  earth’s  magnetism 
was  pervading  the  solution  during  the  whole  time  of  its  rest,  is  more  than  I will  ven- 
ture to  say. 

2579.  The  following  are  considerations  which  bear  upon  this  great  question  (2576.) 
of  an  original  or  an  induced  state. 

2580.  In  the  first  place,  the  bismuth  carries  off  no  power  or  particular  state  from 
the  magnetic  field,  able  to  make  it  affect  a magnet  (2504.) ; so  that  if  the  condition 
acquired  by  the  crystal  be  an  induced  condition,  it  is  probably  a transient  one,  and 
continues  only  v/hilst  under  induction.  The  fact  therefore,  though  negative  in  its 
evidence,  agrees,  as  far  as  it  tells,  with  that  supposition. 

2581.  In  the  next  place,  if  the  effect  were  wholly  due,  as  far  as  the  crystal  is  con- 
cerned, to  an  original  power  inherent  in  the  mass,  we  might  expect  to  find  the  earth’s 
magnetism,  or  any  weak  magnet,  affecting  the  crystal.  It  is  true  that  a weak  mag- 
netie  force  ought  to  induce  any  given  condition  in  a crystal  of  bismuth  just  as  well 
as  a stronger,  only  proportionally.  But  if  the  given  condition  were  inherent  in  the 
crystal,  and  did  not  change  in  its  amount  by  the  degree  of  magnetic  force  to  which 
it  was  subjected,  then  a weak  magnetic  force  ought  to  act  more  decidedly  on  the 
bismuth  than  it  would  do  if  the  condition  were  induced  in  the  bismuth,  and  only  in 
proportion  to  its  own  force.  Whatever  the  value  of  the  argument,  I was  induced  to 
repeat  the  experiment  of  the  earth’s  influence  (2505.)  very  carefully,  and  by  shelter- 
ing the  suspended  crystals  in  small  flasks  or  jar  contained  within  the  larger  covering 
jar,  and  making  the  experiment  in  an  underground  plaee  of  uniform  and  constant 
temperature,  I was  able  to  exclude  every  effect  of  currents  of  air,  so  that  the  crystals 
obeyed  the  slightest  degree  of  torsion  given  to  the  suspending  fibre  by  the  index 
above.  Under  these  circumstances  I could  obtain  no  indications  of  pointing  by 


30  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

the  earth’s  action,  either  with  crystals  of  bismuth  or  of  sulphate  of  iron.  Perhaps  at 
the  equator,  where  the  lines  of  force  are  horizontal,  they  might  be  rendered  sensible. 

2582.  In  the  third  place,  assuming  that  there  is  an  original  force  in  the  crystals 
and  their  molecules,  it  might  be  expected  that  they  would  show  some  direct  influence 
upon  each  other,  independent  of  the  magnetic  force,  and  if  so  the  best  possible  argu- 
ment would  be  thus  obtained  that  the  force  which  is  rendered  manifest  in  the  mag- 
netic field  was  inherent  in  them.  But  on  placing  a large  crystal  with  its  magnecry- 
stallic  axis  horizontal  under  a smaller  and  suspended  one,  or  side  by  side  with  it,  I 
could  procure  no  signs  of  mutual  action;  even  when  the  approximated  parts  of  the 
crystals  were  ground  or  dissolved  away,  so  as  to  let  the  two  masses  come  as  near  as 
possible  to  each  other,  having  large  surfaces  at  the  smallest  possible  distance.  Ex- 
treme care  is  required  in  such  experiments  (2581.),  or  else  many  results  are  produced 
which  seem  to  show  a mutual  affection  of  the  bodies. 

2583.  Neither  could  I find  any  trace  of  mutual  action  between  crystals  of  bismuth, 
or  of  sulphate  of  iron,  when  they  were  both  in  the  magnetic  field,  the  one  being  freely 
suspended  and  the  other  brought  in  various  positions  near  to  it. 

2584.  From  the  absence  therefore  or  extreme  weakness  of  any  power  in  the  crystals 
to  affect  each  other,  and  also  from  the  action  of  heat  which  can  take  away  the  power 
of  the  crystal  before  it  has  lost  its  mere  crystalline  condition  (2570.),  I am  induced 
to  believe  that  the  force  manifested  in  the  crystal  when  in  the  magnetic  field,  which 
appears  by  external  actions,  and  causes  the  motion  of  the  mass,  is  chiefly  and  almost 
entirely  induced,  in  a manner,  subject  indeed  to  the  crystalline  force,  and  finally  ad- 
ditive to  it ; but  at  the  same  time  exalting  the  force  and  the  effects  to  a degree  which 
they  could  not  have  approached  without  the  induction. 

2585.  In  that  case  the  word  magnetocrystallic  ought  probably  to  be  applied  to 
this  force,  as  it  is  generated  or  developed  under  the  influence  of  the  magnet.  The 
word  magnecrystallic  I used  purposely  to  indicate  that  whieh  I believed  belonged  to 
the  crystal  itself,  and  I shall  still  speak  of  the  magnecrystallic  axis,  &c.  in  that 
sense. 

2586.  This  force  appears  to  me  to  be  very  strange  and  striking  in  its  character. 
It  is  not  polar,  for  there  is  no  attraction  or  repulsion.  Then  what  is  the  nature  of  the 
mechanieal  force  which  turns  the  crystal  round  (2460.),  or  makes  it  affect  a magnet 
(2564.)  ? It  is  not  like  a turning*  helix  of  wire  acted  on  by  the  lines  of  magnetic  force  ; 
for  there,  there  is  a current  of  electricity  required,  and  the  ring  has  polarity  all  the 
time  and  is  powerfully  attracted  or  repelled*. 

2587-  If  we  suppose  for  a moment  that  the  axial  position  is  that  in  which  the 
crystal  is  unaffected,  and  that  it  is  in  the  oblique  position  that  the  magneerystallic 
axial  direction  is  affected  and  rendered  polar,  giving  two  tensions  pulling  the 
crystal  round,  then  there  ought  to  be  attractions  at  these  times,  and  an  obliquely 

* Perhaps  these  points  may  find  their  exphcation  hereafter  in  the  action  of  contiguous  particles  (ItifiS.  1710. 
1729.  1735.  2443.). 


MAGNECRYSTALLIC  FORCE — SUPPOSITIONS  AS  TO  ITS  NATURE. 


31 


presented  crystal  ought  to  be  attracted  by  a single  pole,  or  the  nearest  of  two  poles  ; 
but  no  action  of  this  kind  appears. 

2588.  Or  we  might  suppose  that  the  crystal  is  a little  more  apt  for  magnetic  in- 
duction, or  a little  less  apt  for  diamagnetic  induction,  in  the  direction  of  the  magne- 
crystallic  axis  than  in  other  directions.  But,  if  so,  it  should  surely  show  polar  attrac- 
tions in  the  case  of  the  magnetic  bodies,  as  sulphate  of  iron  (2557-  2583.)  ; and  in 
the  case  of  diamagnetic  bodies,  as  bismuth,  a difference  in  the  degree  of  repulsion 
when  presented  wdth  the  magnecrystallic  axis  parallel  and  perpendicular  to  the  lines 
of  magnetic  force  (2552.)  ; which  it  does  not  do. 

2589.  1 do  not  remember  heretofore  such  a case  of  force  as  the  present  one,  where 
a body  is  brought  into  position  only,  without  attraction  or  repulsion. 

2590.  If  the  power  be  induced,  it  must  be  like,  generally,  to  its  inducing  predomi- 
nants ; and  these  are,  at  present,  the  magnetic  and  electric  forces.  If  induced,  sub- 
ject to  the  crystalline  force  (2577.)5  if  must  show  an  intimate  relation  between  it  and 
them.  How  hopeful  we  may  be,  therefore,  that  the  results  will  help  to  throw  open 
the  doors  which  may  lead  us  to  a full  knowledge  of  these  powders  (2146.),  and  the 
combined  manner  in  which  they  dwell  in  the  particles  of  matter,  and  exert  their  in- 
fluence in  producing  the  vvonderful  phenomena  which  they  present. 

2591.  I cannot  resist  throwing  forth  another  view  of  these  phenomena  which  may 
possibly  be  the  true  one.  The  lines  of  magnetic  force  may  perhaps  be  assumed  as 
in  some  degree  resembling  the  rays  of  light,  heat,  &c. ; and  may  find  difficulty  in 
passing  through  bodies  and  so  be  affected  by  them,  as  light  is  affected.  They  may, 
for  instance,  when  a crystalline  body  is  interposed,  pass  more  freely,  or  with  less  dis- 
turbance, through  it  in  the  direction  of  the  magnecrystallic  axis  than  in  other 
directions.  In  that  case,  the  position  which  the  erystal  takes  in  the  magnetic  field 
with  its  magnecrystallic  axis  parallel  to  the  lines  of  magnetic  force,  may  be  the  po- 
sition of  no,  or  of  least  resistance ; and  therefore  the  position  of  rest  and  stable 
equilibrium.  All  the  diametral  effects  wmuld  agree  with  this  view.  Then,  just  as 
the  optie  axis  is  to  a ray  of  polarized  light,  namely,  the  direction  in  which  it  is  not 
affected,  so  would  the  magnecrystallic  axis  be  to  the  lines  of  magnetic  force.  If  such 
were  the  case,  then,  also,  as  the  phenomena  are  developed  in  crystalline  bodies,  we 
might  hope  for  the  discovery  of  a series  of  effects  dependent  upon  retardation  and 
influenee  in  direction,  parallel  to  the  beautiful  phenomena  presented  by  light  with 
similar  bodies.  In  making  this  supposition,  I do  not  forget  the  points  of  inertia  and 
momentum ; but  such  an  idea  as  I can  form  of  inertia  does  not  exclude  the  above 
view  as  altogether  irrational.  I remember  too,  that,  when  a magnetic  pole  and  a 
wire  carrying  an  electric  current  are  fastened  together,  so  that  one  cannot  turn  with- 
out the  other,  if  the  one  be  made  axis  the  other  will  revolve  round  and  carry  the  first 
with  it;  and  also,  that  if  a magnet  be  floated  in  mercury  and  a current  sent  down  it, 
the  magnet  will  revolve  by  the  powers  which  are  within  its  mass.  With  my  imperfect 
mathematical  knowledge,  there  seems  as  much  difficulty  in  these  motions  as  in  the 


32  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

one  I am  supposing-,  and  therefore  I venture  to  put  forth  the  idea*.  The  hope  of  a 
polarized  bundle  of  magnetic  forces  is  enough  of  itself  to  make  one  work  earnestly 
with  such  an  object,  though  only  in  imagination,  before  us  ; and  I may  well  say  that 
no  man,  if  he  take  industry,  impartiality  and  caution  with  him  in  his  investigations 
of  science,  ever  works  experimentally  in  vain. 

2592.  I have  already  referred,  in  the  former  paper  (2469.),  to  Plucker’s  beautiful 
discovery  and  results  in  reference  to  the  repulsion  of  the  optic  axis^f-  of  certain  crystals 
by  the  magnet,  and  have  distinguished  them  from  my  own  obtained  with  bismuth, 
antimony  and  arsenic,  which  are  not  cases  of  either  repulsion  or  attraction  ; believing 
then,  with  Plucker,  that  the  force  there  manifested  is  an  optic  axis  force,  exerted  in 
the  equatorial  direction ; and  therefore  existing  in  a direction  at  right  angles  to  that 
which  produces  the  magnecrystallic  phenomena. 

2593.  But  the  relations  of  both  to  crystalline  structure,  and  therefore  to  the  force 
which  confers  that  condition,  are  most  evident.  Other  considerations  as  to  position, 
set,  and  turning,  also  show  that  the  two  forces,  so  to  say,  have  a very  different  rela- 
tion to  each  other  to  that  which  exists  between  them  and  the  magnetic  or  diamag- 
netic force.  As,  therefore,  this  strong  likeness  on  the  one  hand,  and  distinct  sepa- 
ration on  the  other  is  clearly  indicated,  I will  endeavour  to  compare  the  two  sets  of 
effects,  with  the  view  of  ascertaining  whether  the  force  exerted  in  producing  them  is 
not  identical. 

2594.  I had  the  advantage  of  verifying  Plucker’s  results  under  his  own  personal 
tuition  in  respect  of  tourmaline,  stanrolite,  red  ferro-prussiate  of  potassa,  and  Iceland 
spar.  Sinee  then,  and  in  reference  to  the  present  inquiry,  I have  carefully  examined 
calcareous  spar,  as  being  that  one  of  the  bodies  which  was  at  the  same  time  free 
from  magnetic  action,  and  so  simple  in  its  crystalline  relations  as  to  possess  but  one 
optie  axis. 

2595.  When  a small  rhomboid,  about  0’3  of  an  inch  in  its  greatest  dimension,  is 
suspended,  with  its  optic  axis  horizontal,  between  the  pointed  poles  (2458.)  of  the 
electro-magnet,  approximated  as  closely  as  they  can  be,  to  allow  free  motion,  the 
rhotnboid  sets  in  the  equatorial  direction,  and  the  optic  axis  coincides  with  the  mag- 
netic axis ; but,  if  the  poles  be  separated  to  the  distance  of  half,  or  three-quarters  of 
an  inch,  the  rhomboid  turned  through  90®,  and  set  with  the  optic  axis  in  the  equato- 
rial direction,  and  the  greatest  length  axial.  In  the  first  instance  the  diamagnetic 
force  overcame  the  optic  axis  force;  in  the  second  the  optic  axis  force  was  the 
stronger  of  the  two. 

2596.  To  remove  the  diamagnetic  effect  I used  flat  poles  (2463.),  and  then  the  little 
rhomboid  always  set  in,  or  vibrated  about,  that  position  in  which  its  optic  axis  was 
equatorial. 

* See  note  (2639.)  at  the  end. 

t On  the  Repulsion  of  the  Optic  Axes  of  Crystals  hy  the  Poles  of  a Magnet,  Poggendoeff’s  Annalen,  vol. 
Ixxii.,  October  1847,  or  Taylor's  Scientific  Memoirs,  vol.  v.  p.  353. 


MAGiNECRYSTALLIC  FORCE — ITS  NATURE  CONSIDERED. 


33 


2597.  I also  took  three  cubes  of  calcareous  spar  (1695.),  in  which  the  optic  axes 
were  perpendicular  to  two  of  the  faces,  of  the  respective  dimensions  of  0*3,  0’5,  and 
0-8  of  an  inch  in  the  side,  and  placed  these  in  succession  in  the  magnetic  field,  be- 
tween either  flat  or  pointed  poles.  In  all  cases,  the  optic  axis,  if  horizontal,  passed 
into  the  equatorial  position  ; or,  if  vertical,  left  the  cubes  indifferent  as  to  direction. 
It  was  easy  by  the  method  of  two  positions  (2470.)  to  find  the  line  of  force,  which, 
being  vertical,  left  the  mass  unaffected  by  the  magnet ; or,  being  horizontal,  went 
into  the  equatorial  position ; and  then  examining  the  cube  by  polarized  light,  it  was 
found  that  this  line  coincided  with  the  optic  axis. 

2598.  Even  the  horse-shoe  magnet  (2485.)  is  sufficiently  strong  to  produce  these 
effects. 

2599.  I tried  two  similar  cubes  of  rock-crystal  (1692.),  but  could  perceive  no  traces 
of  any  phenomena  having  either  magneoptic,  or  magnecrystallic,  or  any  other  rela- 
tion to  the  crystalline  structure  of  the  masses. 

2600.  But  though  it  is  thus  very  certain  that  there  is  a line  in  a crystal  of  calca- 
reous spar  coinciding  with  the  optic  axis,  which  line  seems  to  represent  the  resultant 
of  the  forces  which  make  the  crystal  take  up  a given  position  in  the  magnetic  field  ; 
and,  though  it  is  equally  certain  that  this  line  takes  up  its  position  in  the  equatorial 
direction ; yet,  considered  as  a line  of  force,  i.  e.  as  representing  the  direction  of  the 
force  which  places  the  crystal  in  that  position,  it  seems  to  me  to  have  something 
anomalous  in  its  character.  For,  that  a directing  and  determining  line  of  force 
should  have,  as  its  full  effect,  the  result  of  going  into  a plane  (the  equatorial),  in 
which  it  can  take  up  any  one  of  an  infinite  number  of  positions  indifferently,  leaves 
an  imperfect  idea  on  my  mind ; and  a thought,  that  there  is  some  other  effect  or  re- 
sidual phenomena  to  be  recognized  and  accounted  for. 

2601.  On  further  consideration,  it  appears  that  a simple  combination  of  the  mag- 
necrystalline  condition,  as  it  exists  in  bismuth,  will  supply  us  with  a perfect  repre- 
sentation of  the  state  of  calcareous  spar  ; for,  by  placing  two  equal  pieces  of  bismuth 
with  their  magnecrystallic  axes  perpendicular  to  each  other  (2484.),  we  have  a system 
of  forces  whieh  seems  to  possess,  as  a resultant,  a line  setting  in  the  equatorial  direc- 
tion. When  that  line  is  vertical  the  system  is,  as  regards  position,  indifferent ; but 
when  horizontal,  the  system  so  stands,  that  the  line  is  in  the  equatorial  plane.  Still, 
the  real  force  is  not  in  the  equatorial  direction,  but  axial ; and  the  system  is  moved 
by  what  maybe  considered  deplane  of  axial  force  (resulting  from  the  union  of  the  two 
axes  at  right  angles  to  each  other),  rather  than  by  a line  of  equatorial  force. 

2602.  Doubtless,  the  rhomboid  or  cube  (2597.)  of  calcareous  spar  is  not  a com- 
pound crystal,  like  the  system  of  bismuth  crystals  just  referred  to  (2601.);  but  its 
molecules  may  possess  a compound  disposition  of  their  forces,  and  may  have  two  or 
more  axes  of  power,  which  at  the  same  time  that  they  cause  the  crystalline  structure, 
may  exert  such  force  in  relation  to  the  magnet,  as  to  give  results  in  the  same  manner, 
and  of  the  same  kind,  as  those  of  the  double  crystal  of  bismuth  (2601.).  Indeed, 

MDCCCXLIX.  F 


34  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


that  there  should  be  but  one  axis  of  crystalline  force,  either  in  the  particle  of  Iceland 
spar,  or  in  those  of  bismuth,  does  not  seem  to  me  to  be  any  way  consistent  with  the 
cleavage  of  the  substances  in  three  or  more  directions. 

2603.  The  optic  axis  in  a piece  of  calcareous  spar,  is  simply  the  line  in  which,  if  a 
polarized,  or  ordinary  ray  of  light  moves,  it  is  the  least  affected.  It  may  be  a line  which, 
as  a resultant  of  the  molecular  forces,  is  that  of  the  least  intensity  ; and,  certainly,  as 
regards  ordinary  and  mechanical  means  of  observing  cohesion,  a piece  of  calcareous 
spar  is  sensibly,  and  much  harder  on  the  faces  and  parts  which  are  parallel  to  the 
optic  axis,  than  on  those  perpendicular  to  it.  An  ordinary  file  or  a piece  of  sand- 
stone shows  this.  So  that  the  plane  equatorial  to  the  optic  axis,  as  it  represents 
directions  in  which  the  force  causing  crystallization  is  greater  in  degree  than  in  the 
direction  of  the  optic  axis,  may  also  be  that  in  which  the  resultant  of  its  magne- 
crystallic  force  is  exerted. 

2604.  I am  bound  to  state,  as  in  some  degree  in  contrast  with  such  considerations, 
that,  with  bismuth,  antimony  and  arsenic,  the  cleavage  is  very  facile  perpendicular  to 
the  magnecrystallic  axis  (2475.  25 10. *2532.).  But  we  must  remember  that  the 
cleavage  (and  therefore  the  cohesive)  force  is  not  the  only  thing  to  be  considered, 
for  in  calcareous  spar  it  does  not  coincide  with  either  the  axial  or  the  equatorial 
direction  of  the  substance  in  the  magnetic  field : we  must  endeavour  to  look  beyond 
this  to  the  polar  (or  axial)  condition  of  the  particles  of  the  masses,  for  the  full  un- 
derstanding and  true  relation  of  all  these  points. 

2605.  I am  bound,  also,  to  admit  that,  if  we  consider  calcareous  spar  as  giving  the 
simple  system  of  force,  we  may,  by  the  jaxtaposition  of  two  crystals  with  their  optic 
axes  at  right  angles  to  each  other,  produce  a compound  mass,  which  will  truly  repre- 
sent the  bismuth  in  the  direction  of  the  force ; i.  e.  it  will,  in  the  magnetic  field, 
point  with  apparently  one  line  of  force  only,  and  that  in  the  axial  direction,  whilst  it 
may  be  really  moved  by  a system  of  forces  lying  in  the  equatorial  plane.  I will  not 
at  present  pretend  to  say  that  this  is  not  the  state  of  things ; but  I think,  however, 
that  the  metals,  bismuth,  antimony  and  arsenic,  present  us  with  the  simplest  as  they 
do  the  strongest  cases  of  magnecrystallic  force ; and  whether  that  be  so  or  not  I am 
still  of  opinion  that  the  phenomena  discovered  by  Plucker  and  those  of  which  I have 
given  an  account  in  these  two  papers,  have  one  common  origin  and  cause. 

2606.  I went  through  all  the  experiments  and  reasonings  with  Plucker’s  crystals 
(as  the  carbonate  of  lime,  tourmaline  and  red  ferro-prussiate  of  potassa),  in  reference 
to  the  question  of  original  or  induced  power  (2576.),  as  before,  and  came  to  the 
same  conclusion  as  in  the  former  case  (2584.). 

2607-  I could  not  find  that  crystals  of  red  ferro-prussiate  of  potassa  or  tourmaline 
were  affected  by  the  earth’s  magnetism  (2581.),  or  that  they  had  the  power  of  affect- 
ing each  other  (2582.).  Neither  could  I find  that  Plucker’s  effect  with  calcareous 
spar,  or  red  ferro-prussiate  of  potassa,  was  either  an  attractive  or  repulsive  effect, 
but  one  connected  with  position  only  (2550. 2560.).  All  which  circumstances  tend  to 


MAGNECRYSTALLIC  FORCE — MAGNETO-OPTIC  FORCE. 


35 


convince  me  that  the  force  active  in  his  experiments,  and  that  in  my  results  with 
bismuth,  &c.,  is  the  same*. 

2608.  A small  rhomboid  of  Iceland  spar  was  raised  to  the  highest  temperature  in 
the  magnetic  field  which  a spirit-lamp  could  give  (2570.) ; it  was  at  least  equal  to 
the  full  red  heat  of  copper,  but  it  pointed  as  well  then  as  before.  A short  thick  tour- 
maline was  heated  to  the  same  degree,  and  it  also  pointed  equally  well.  As  it  cooled, 
however,  it  became  highly  magnetic,  and  seemed  to  be  entirely  useless  for  experiments 
at  low  temperatures  ; but  on  digesting  it  for  a few  seconds  in  nitromuriatic  acid,  a 
little  iron  was  dissolved  from  the  surface,  after  which  it  pointed  as  well,  and  in  ac- 
cordance with  Plucker’s  law,  as  before.  A little  peroxide  upon  the  surface  had  been 
reduced  by  the  flame  and  heat  to  protoxide,  and  caused  the  magnetic  appearances. 


2609.  There  is  a general  and,  as  it  appears  to  me,  important  relation  between 
Plucker’s  magneto-optical  results  and  those  I formerly  obtained  with  heavy  glass 
and  other  bodies  (2152,  &c.).  When  any  of  these  bodies  are  subject  to  strong  induc- 
tion under  the  influence  of  the  magnetic  or  electric  forces,  they  acquire  a peculiar 
state,  in  which  they  can  influence  a polarized  ray  of  light.  The  effect  is  a rotation 
of  the  ray,  if  it  be  passed  through  the  substance  parallel  to  the  lines  of  magnetic 
force,  or  in  other  words,  in  the  axial  direction  ; but  if  it  be  passed  in  the  equatorial 
direction,  no  effect  is  produced.  The  equatorial  plane,  therefore,  is  that  plane  in 
which  the  condition  of  the  molecular  forces  is  the  least  disturbed  as  respects  their 
influence  on  light.  So  also  in  Plucker’s  results,  the  optic  axis,  or  the  optic  axes,  if 
there  be  two,  go  into  that  plane  under  the  same  magnetic  influence,  they  also  being’ 
the  lines  in  which  there  is  the  least,  or  no  action  on  polarized  light. 

2610.  If  a piece  of  heavy  glass,  or  a portion  of  water,  could  be  brought  before- 
hand into  this  constrained  condition,  and  then  placed  in  the  magnetic  field,  I think 
there  can  be  no  doubt  that  it  would  move,  if  allowed  to  do  so,  and  place  itself 
naturally,  so  that  the  plane  of  no  action  on  light  should  be  equatorial,  just  as 
Plucker  shows  that  a crystal  of  calcareous  spar  or  tourmaline  does  in  his  experi- 
ments. And,  as  in  his  case,  the  magnetic  or  diamagnetic  character  of  the  bodies, 
makes  no  difference  in  the  general  result ; so  in  my  experiments,  the  optical  effect  is 
produced  in  the  same  direction,  and  subject  to  the  same  laws,  with  both  classes  of 
substances  (2185.  2187-). 

2611.  But  though  thus  generally  alike  in  this  great  and  leading  point,  there  is  still 
a vast  difference  in  the  disposition  of  the  forces  in  the  heavy  glass  and  the  crystal ; 

* The  optic  axis  is  the  direction  of  least  optic  force ; and  by  Plucker’s  experiments,  coincides  with  what 
I consider  in  my  results  as  the  direction  of  minimum  magnecrystallic  force.  It  is  more  than  probable  that, 
wherever  the  two  sets  of  effects  (whether  really  or  only  nominally  different)  can  be  recognized  in  the  same 
body,  the  directions  of  maximum  effect,  and  also  those  of  minimum  effect,  will  be  found  to  coincide. — No- 
vember 23,  1848. 

F 2 


36  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 

and  there  is  a still  greater  difference  in  this,  that  the  heavy  glass  takes  up  its  state 
only  for  a time  by  constraint  and  under  induction,  whilst  the  crystal  possesses  it 
freely,  naturally  and  permanently.  In  both  cases,  however,  whether  natural  or  in- 
duced, it  is  a state  of  the  particles  ; and  comparing  the  effect  on  light  of  the  glass 
under  constraint  with  that  of  the  crystal  at  liberty,  it  indicates  a power  in  the  mag- 
net of  inducing  something  like  that  condition  in  the  particles  of  matter  whieh  is 
necessary  for  crystallization  ; and  that  even  in  the  partieles  of  fluids  (2184.). 

2612.  If  there  be  any  weight  in  these  considerations,  and  if  the  forces  manifested 
in  the  crystals  of  bismuth  and  Iceland  spar  be  the  same  (2607.),  then  there  is  further 
reason  for  believing  that,  in  the  case  of  bismuth  and  the  other  metals  named,  there  is, 
when  they  are  subjected  to  the  power  of  the  magnet,  both  an  induced  condition  of 
force  (2584.),  and  also  a pre-existing  force  (2577*) • The  latter  may  be  distinguished 
as  the  crystalline  force,  and  is  shown,  first,  by  such  bodies  exhibiting  optic  axes  and 
lines  of  foree  when  not  under  induetion  ; by  the  symmetric  condition  of  the  whole 
mass,  produced  under  circumstances  of  ordinary  occurrence  ; and  by  the  fixity  of 
the  line  of  magnecrystallic  force  in  the  bodies  shown  experimentally  to  possess  it. 

2613.  Though  I have  spoken  of  the  magnecrystallic  axis  as  a given  line  or  direc- 
tion, yet  I would  not  wish  to  be  understood  as  supposing  that  the  force  decreases, 
or  state  changes,  in  an  equal  ratio  all  round  from  it.  It  is  more  probable  that  the 
variation  is  different  in  degree  in  different  directions,  dependent  on  the  powers  whieh 
give  difference  of  form  to  the  crystals.  The  knowledge  of  the  disposition  of  the  force 
can  be  ascertained  minutely  hereafter,  by  the  use  of  good  crystals,  an  unchangeable 
ordinary  magnet  (2485.  2528.),  or  a regulated  electro-magnet,  flat-faced  poles  (2463.), 
and  torsion  (2500.  2530.). 

2614.  I cannot  conclude  this  series  of  researches  without  remarking  how  rapidly 
the  knowledge  of  molecular  forces  grows  upon  us,  and  how  strikingly  every  investi- 
gation tends  to  develope  more  and  more  their  importance,  and  their  extreme  attrac- 
tion as  an  object  of  study.  A few  years  ago  magnetism  was  to  us  an  occult  power, 
affecting  only  a few  bodies  ; now  it  is  found  to  influence  all  bodies,  and  to  possess 
the  most  intimate  relations  with  electricity,  heat,  chemical  action,  light,  crystalliza- 
tion, and,  through  it,  with  the  forces  concerned  in  cohesion  ; and  we  may,  in  the 
present  state  of  things,  well  feel  urged  to  continue  in  our  labours,  encouraged  by  the 
hope  of  bringing  it  into  a bond  of  union  with  gravity  itself. 

Royal  Institution, 

October  20,  1848. 


MAGNECRYSTALLIC  CONDITION  OF  SULPHATE  OF  IRON. 


37 


^ vi.  Note. — On  the  position  of  a crystal  of  sulphate  of  iron  in  the  magnetic  field. 

Received  December  7,  1848. — Read  December  7,  1848. 

2615.  Though  effects  of  the  following  nature  are  general, 
yet  I think  it  convenient  to  state  that  I obtained  them  chiefly 
by  the  use  of  magnetic  poles  (224705  form  of  which  is  given 
in  the  plan  and  side  view  annexed  (fig.  6.).  The  crystals  submit- 
ted to  their  action  were  suspended  by  cocoon  silk,  so  as  to  be 
level  with  the  upper  surface  of  the  poles. 

2616.  A prismatic  crystal  of  proto-sulphate  of  iron  was  selected,  which  was  nearly 
0‘9  of  an  inch  in  length,  OT  in  breadth,  and  0’05  in  thickness;  by  examination  the 
magnecrystallic  axis  was  found  to  coincide  with  the  thickness,  and  therefore  to  be 
perpendicular,  or  nearly  so  (2546.),  to  the  plate.  Being  suspended  as  above  described, 
and  the  magnet  (22470  excited  by  ten  pair  of  Grove’s  plates,  the  crystal  stood  trans- 
verse, or  with  its  magnecrystallic  axis  parallel  to  the  axis  of  magnetic  force,  when  the 
distance  between  the  poles  was  2’25  inches  or  more ; but  when  the  distance  was 
about  two  inches  or  less,  then  it  stood  with  its  length  axial,  or  nearly  so,  and  its 
magnecrystallic  axis  therefore  transverse  to  the  lines  of  magnetic  force.  In  the  in- 
termediate distances  between  2 and  2*25  inches,  the  prism  assumed  an  oblique 
position  (2634.),  more  or  less  inclined  to  the  axial  line,  and  so  passing  gradually  from 
the  one  position  to  the  other.  This  intermediate  distance  I will  for  the  present  call 
n (neutral)  distance. 

2617-  If  the  poles  be  two  inches  apart  and  the  crystal  be  gradually  lowered,  it 
passes  through  the  same  intermediate  oblique  positions  into  the  transverse  position  ; 
or  if  the  crystal  be  raised,  the  same  transitions  occur ; at  any  less  distance  the  changes 
are  the  same,  but  later.  They  occur  more  rapidly  when  the  crystal  is  raised  than 
when  it  is  lowered  ; but  this  is  only  because  of  the  unsymmetric  disposition  and  in- 
tensity of  the  lines  of  magnetic  force  around  the  magnetic  axis,  due  to  the  horse-shoe 
form  of  the  magnet  and  shape  of  the  poles.  If  two  cylinder  magnets  with  equal 
conical  terminations  were  employed,  there  is  no  doubt  that  for  equal  amounts  of 
elevation  or  depression,  corresponding  changes  would  take  place  in  the  position  of 
the  crystal. 

2618.  These  changes  however  are  not  due  to  mere  diminution  of  the  magnetic 
force  by  distance,  but  to  differences  in  the  forms  or  direction  of  the  resultants  of  force. 
This  is  shown  by  the  fact  that,  if  the  crystal  be  left  in  its  first  position,  and  so  point- 
ing with  the  length  axially,  no  diminution  of  the  force  of  the  magnet  alters  the 
position  ; thus,  whether  one  or  ten  pair  of  plates  be  used  to  excite  the  magnet,  the  n 
distance  (2616.)  remains  unchanged;  and  even  descending  to  the  use  of  an  ordinary 
horse-shoe  magnet,  I have  found  the  same  result. 

2619.  Variation  in  the  length  of  the  prismatic  crystal  has  an  important  influence 


Fig.  6. 


38  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


over  the  result.  As  the  crystal  is  shorter  the  distance  n diminishes,  all  the  other 
phenomena  remaining'  the  same.  A crystal  0*7  of  an  inch  long,  but  thicker  than  the 
last,  had  for  its  maximum  n distance  1*7  inch.  A still  shorter  crystal  had  for  its 
maximum  n distance  1*1  inch.  In  all  these  cases  variation  of  the  force  of  the  mag- 
net caused  no  sensible  change. 

2620.  Variation  in  that  dimension  of  the  crystal  coincident  with  the  rnagnecry- 
stallic  axis  affected  the  n distance  : thus,  increase  in  the  length  of  the  magnecrystallic 
axis  diminished  the  distance,  and  diminution  of  it  in  that  direction  increased  the 
distance.  This  was  shown  in  two  ways  ; first,  by  placing  a second  prismatic  crystal 
by  the  side  of  the  former  in  a symmetric  position  (2636.),  which  reduced  the  n 
distance  to  between  1*76  and  2 inches  ; and  next,  by  employing  two  crystals  in  suc- 
cession of  the  same  length  but  different  thicknesses.  The  thicker  one  had  the  smaller 
n distance. 

2621.  Variation  in  the  depth  of  the  crystal,  i.  e.  its  vertical  dimension,  did  not 
produce  any  sensible  effect  on  the  n distance  : nor  by  theory  should  it  do  so,  until 
the  extension  upwards  or  downwards  brings  the  upper  or  lower  parts  into  the  con- 
dition of  raised  or  depressed  portions  (2617.)- 

2622.  Variation  in  the  form  of  the  poles  affects  the  n distance.  As  they  are  more 
acute,  the  distance  increases ; and  as  they  are  more  obtuse  up  to  flat-faced  poles 
(2463.),  the  distance  diminishes. 

2623.  With  the  shorter  crystals,  or  with  obtuse  poles,  it  is  often  necessary  to 
diminish  the  power  of  the  magnet,  or  else  the  crystal  is  liable  to  be  drawn  to  the  one 
or  other  pole.  This,  however,  may  be  avoided  by  employing  a vertical  axis  which  is 
confined  below  as  well  as  above  (2554.)  ; and  then  the  difference  in  strength  of  the 
magnet  is  shown  to  be  indifferent  to  the  results,  or  very  nearly  so. 


2624.  These  effects  may  probably  be  due  to  the  essential  difference  which  exists 
between  the  ordinary  magnetic  and  the  magnecrystallic  action,  in  that  the  first  is 
polar,  and  the  second  only  axial  (2472.)  in  character.  If  a piece  of  magnetic  matter, 
iron  for  instance,  be  in  the  magnetic  field,  it  immediately  becomes  polar  (i.  e.  has 
terminations  of  different  qualities).  If  many  iron  particles  be  there,  they  all  become 
polar ; and  if  they  be  free  to  move,  arrange  themselves  in  the  direction  of  the  axial 
line,  being  joined  to  each  other  by  contrary  poles  ; and  by  that  the  polarity  of  the 
extreme  particles  is  increased.  Now  this  does  not  appear  to  be  at  all  the  case  with 
particles  under  the  influence  of  the  magnecrystallic  force;  the  force  seems  to  be 
altogether  axial,  and  hence  probably  the  difference  above,  and  in  many  other  results. 

2625.  Thus,  if  four  or  more  little  cubes  of  iron  be  suspended  in  a magnetic  field 
of  equal  force  (2465.),  they  will  become  polar;  if  also  four  similar  cubes  of  cry- 
stallized bismuth  be  similarly  circumstanced,  they  will  be  affected  and  point.  If  the 
iron  cubes  be  arranged  together  in  the  direction  of  the  equatorial  line,  they  will  form 


MAGNECRYSTALLIC  CONDITION  OF  SULPHATE  OF  IRON. 


39 


an  aggregate  in  a position  of  unstable  equilibrium,  and  will  immediately,  as  a whole, 
turn  and  point  with  the  length  axially ; whereas  the  bismuth  cubes  by  such  approxi- 
mation will  suffer  no  sensible  change. 

2626.  The  extreme  (and  the  other)  associated  cubes  of  the  elongated  iron  arrange- 
ment now  have  a polar  force  above  that  which  they  had  before  ; and  the  whole  group 
serves,  as  it  were,  as  a conductor  for  the  lines  of  magnetic  power ; for  many  of  them 
concentrate  upon  the  iron,  and  the  intensity  of  power  is  much  stronger  between  the 
ends  of  the  iron  arrangement  and  the  magnetic  poles,  than  it  is  in  other  parts  of  the 
magnetic  field.  k!iuch  is  not  the  case  with  the  bismuth  cubes;  for  however  they  be 
arranged,  the  intensity  of  force  in  the  magnetic  field  is,  as  far  as  experiments  have 
yet  gone,  unaffected  by  them  ; and  the  intensity  of  the  molecules  of  the  crystals  ap- 
pears to  remain  the  same.  Hence  the  iron  stands  lengthways  between  the  poles  ; the 
bismuth  crystals,  on  the  contrary,  whether  arranged  side  by  side,  as  respects  the  mag- 
necrystallic  axis,  so  as  to  stand  as  to  length  equatorially ; or  end  to  end,  so  as  to 
stand  axially,  are  perfectly  indifferent  in  that  respect,  vibrating  and  setting  equally 
both  w^ays. 

2627.  A given  piece  of  iron  when  introduced  into  a field  of  equal  magnetic  force, 
and  brought  towards  the  pole,  adheres  to  it  and  disturbs  the  intensity  of  the  field, 
producing  a pointed  form  of  pole  in  one  part  with  diverging  lines  of  force  : a crystal 
of  bismuth  vibrates  with  sensibly  equal  force  in  every  part  of  the  field  (2467.),  and 
does  not  disturb  the  distribution  of  the  power. 

2628.  Considering  all  these  actions  and  conditions,  it  appears  to  me  that  the  occur- 
rence of  the  n distance  with  a body  which  is  at  the  same  time  magnetic  and  magne- 
crystallic,  may  be  traced  to  that  which  causes  them  and  their  differences,  namely,  the 
polarity  belonging  to  the  magnetic  condition,  and  the  axiality  belonging  to  the  mag- 
necrystallic  condition.  Thus,  suppose  an  uniform  magnetic  field  three  inches  from 
pole  to  pole,  and  a bar  of  magnetic  matter  an  inch  long,  suspended  in  the  middle  of 
it ; by  virtue  of  the  polarity  it  acquires,  it  will  point  axially,  and  carry  on,  or  con- 
duct, with  its  mass,  the  magnetic  force,  so  much  better  than  it  was  conducted  in  the 
same  space  before,  that  the  lines  of  force  between  the  ends  of  this  bar  and  the  mag- 
netic poles,  will  be  concentrated  and  made  more  intense  than  anywhere  else  in  the 
magnetic  field.  If  the  poles  be  made  to  approach  towards  the  bar,  this  effect  will 
increase,  and  the  bar  will  conduct  more  and  more  of  the  magnetic  force,  and  point 
with  proportionate  intensity.  It  is  not  merely  that  the  magnetic  field  becomes  more 
intense  by  the  approximation  of  the  poles,  but  the  proporfion  of  force  carried  on  by 
the  bar  becomes  greater  as  compared  to  that  conveyed  onwards  by  an  equal  space 
in  the  magnetic  field  at  its  side. 

2629.  But  if  a similar  bar  of  magnecrystallic  substance  be  placed  in  the  magnetic 
field,  its  power  does  not  rise  in  the  same  manner,  or  in  the  same  great  proportion, 
by  approximation  of  the  poles.  There  can  be  no  doubt  that  such  approximation 
increases  the  intensity  of  the  lines  of  force,  and  therefore  increases  the  intensity  of 


40  DR.  FARADAY’S  EXPERIMENTAL  RESEARCHES  IN  ELECTRICITY.  (SERIES  XXII.) 


the  magneto-crystallic  state ; but  this  state  does  not  appear  to  be  due  to  polarity, 
and  the  bar  does  not  convey  more  power  through  it  than  is  conveyed  onwards  else- 
where through  an  equal  space  in  the  magnetic  field.  Hence  its  directive  force  does 
not  increase  in  the  same  rapid  degree  as  the  directive  force  of  the  magnetic  bar  just 
referred  to. 

2630.  If  then  we  take  a bar  which,  like  a prism  of  sulphate  of  iron,  is  magnetic, 
and  also  magnecrystallic,  having  the  magnecrystallic  axis  perpendicular  to  its  length, 
such  a bar,  properly  suspended,  ought  to  have  an  n distance  of  the  poles,  within 
which  the  forces  ought  to  be  nearly  in  equilibrium ; whilst  at  a greater  distance  of 
the  poles,  the  magnecrystallic  force  ought  to  predominate  ; and  at  a lesser  distance, 
the  magnetic  force  ought  to  have  the  advantage  ; simply,  because  the  magnetic 
force,  in  consequence  of  the  true  polarity  of  the  molecules,  grows  up  more  rapidly 
and  diminishes  more  rapidly  than  the  magneto-crystallic  force. 

2631.  This  view,  also,  is  consistent  with  the  fact  that  variation  of  the  force  of  the 
magnet  does  not  affect  the  n distanee  (2618.  2619.);  for,  whether  the  force  be 
doubled  or  quadrupled,  both  the  magnetic  and  magneto-crystallic  forces  are  at  the 
same  time  doubled  or  quadrupled ; and  their  proportion  therefore  remains  the  same. 

2632.  The  raising  or  lowering  of  the  crystal  above  or  below  the  line  of  maximum 
magnetic  force  is  manifestly  equivalent  in  principle  to  the  separation  of  the  magnetic 
poles ; and  therefore  should  produce  corresponding  effects : and  that  is  the  case 
(2617.)-  Besides  that,  when  the  crystal  is  raised  above  the  level  of  the  poles,  such 
resultants  of  magnetic  force  as  pass  through  it,  are  no  longer  parallel  to  its  length, 
but  more  or  less  curved,  so  that  they  probably  cannot  act  with  the  same  amount  of 
power  in  throwing  the  whole  crystal  into  a consistent  polarized  magnetic  condition,  as 
if  they  were  parallel  to  it : whereas,  as  respects  the  induction  of  the  magneto-crystallic 
condition,  each  of  the  particles  appears  to  be  affected  independently  of  the  others  ; and, 
therefore,  any  loss  of  an  effect  dependent  upon  joint  action  would  not  be  felt  here. 

2633.  M.  Plucker  told  me,  when  in  England  in  August  last,  that  the  repulsive 
force  on  the  optic  axis  diminishes  and  increases  less  rapidly  than  the  magnetic  force, 
by  change  of  distance;  but  is  not  altered  in  its  proportion  to  the  magnetic  force  by 
employing  a stronger  or  weaker  magnet.  This  is  manifestly  the  same  effeet  as  that 
I have  been  describing ; and  makes  me  still  more  thoroughly  persuaded  that  his 
results  and  mine  are  due  to  one  and  the  same  cause  (2605.  2607.)* 


2634.  I have  said  that,  within  the  n distance,  the  crystal  of  sulphate  of  iron  pointed 
more  or  less  obliquely  (2616.)  ; I will  now  state  more  particularly  what  the  circum- 
stances are.  If  the  distance  n be  so  adjusted,  that  the  prismatic  crystal,  which  is  at 
the  time  between  the  magnetic  poles,  shall  make  an  angle  of  30°  (or  any  quantity) 
with  the  axial  line ; then  it  will  be  found  that  there  is  another  stable  position, 
namely,  the  diametral  position  (2461.),  in  whieh  it  can  stand  ; but  that  the  obliquity 


MAGNECRYSTALLIC  CONDITION  OF  SULPHATE  OF  IRON. 


41 


is  always  on  the  same  side  of  the  axial  line  ; and  that  the  crystal  will  not  stand  with 
the  like  obliquity  of  30°  on  the  opposite  side  of  the  magnetic  axis. 

2635.  If  the  crystal  be  turned  180°  round  a vertical  axis,  or  end  for  end,  then  the 
inclination,  and  the  direction  in  which  it  occurs,  remain  unchanged ; in  fact,  it  is 
simply  giving  the  crystal  the  diametral  position.  But  if  the  crystal  be  revolved  180° 
round  a horizontal  axis  ; either  that  coinciding  with  its  length,  which  represents  its 
maximum  magnetic  direction ; or  that  corresponding  with  its  breadth,  and  therefore 
with  the  magnecrystallic  axis ; then  the  inclination  is  the  same  in  amount  as  before, 
but  it  is  on  the  other  side  of  the  axial  line. 

2636.  This  is  the  case  with  all  the  prismatic  crystals  of  sulphate  of  iron  which  I 
have  tried.  The  elFect  is  very  determinate ; and,  as  would  be  expected,  when  two 
crystals  correspond  in  the  direction  of  the  inclination,  they  also  correspond  in  the 
position  of  their  form  and  direction  of  the  various  planes. 

2637.  All  these  variations  of  position  indicate  an  oblique  resultant  of  setting  force, 
derived  from  the  joint  action  of  the  magnetic  and  magnecrystallic  forces ; and  would 
be  explained  by  tlie  supposition,  that  the  magnecrystallic  axis  or  line  of  maximum 
magnecrystallic  force,  was  not  perpendicular  to  the  chief  planes  of  the  crystal  (or 
those  terminating  it),  but  a little  inclined  in  the  direction  of  the  length. 

2638.  Whether  this  be  the  case,  or  whether  the  maximum  line  of  magnetic  force 
may  not,  even,  be  a little  inclined  to  the  length  of  the  prism  ; still,  the  n distance 
supplies  an  excellent  experimental  opportunity  of  examining  this  inclination,  however 
small  its  quantity  may  be ; because  of  the  facility  with  which  the  influence  of  either 
the  one  or  the  other  may  be  made  predominant  in  any  required  degree. 

Royal  Institution, 

December  5,  1848. 

2639.  IVofe.  (2591.)  Another  supposition  may  be  thrown  out  for  consideration.  I 
have  already  said  that  the  assumption  of  a mere  axial  condition  (2587.2591.)  would 
account  for  the  set  without  attraction  or  repulsion.  Now  if  we  suppose  it  possible 
that  the  molecules  should  become  polar  in  relation  to  the  north  and  south  poles  of 
the  magnet,  but  with  no  mutual  relation  amongst  themselves,  then  the  bismuth  or 
other  crystal  might  set  as  if  induced  with  mere  axial  power : but  it  seems  to  me  very 
improbable  that  polarities  of  a given  particle  in  a crystal  should  be  subject  to  the  in- 
fluence of  the  polarities  of  the  distant  magnet  poles,  and  not  also  to  the  like  polarities 
of  the  contiguous  particles. — January  24,  1849. 


MDCCCXLIX. 


G 


1 


■T.IJUJ-;;  ,1.,: 


'>v^r:  ' 


frnij.  ,,’Uf7  a-ii  j::/;) 'j’a  ■ - ■•  ■-  ■ ' , 

(T  . jfr':  .-v,-;'  - - 'I  ■ -■■  :.■  , . • ■ . ' ■ . .u. 


i' ,r  ' i >vrr>'.  ly  i ';.,  >j;  Jj'O-  .; 

J'.i  .'■«  'ii  ' i’i 'i;.,  . ■'■.  h'-;:'' 


■i'i  'f'  JH'f  ; I 


■ - 1'  I 

..  U i v^4.  'f 


y h.  i.'  j;:  yr 'y.y (‘i  'ii':  i hi 


..H'-tif'.  ■', 


!;  • ■ '•■■■K  \ i'. 


.1.,' •’■  !‘*  'ti' 


‘ l.i  "If 

''iV'i-i  isV^'Vl  ’:;v>  *>7:  .r,V)7';':;i  ;, ; /jyif'rfJl',,.  ^ ■.  , ,'■' ,:,,i{  li'iA. 'jii.  iri.fif ,■.!)■ 

*^•1' t'  ; ’.  '•  'i*r  ‘tsj  ■,  .- fv,'' • , 

::;  ^jih  ■ .i:  7;  4 -l- 


Jk>ty-  ‘t'* 


'd'.'  ..■ : .-  '4:v  ■:,  .;;  - 

|i:v7;  'I'f  ,s.  ' V '/t,s  7:-  r .Tf  ??'  ■ yii^' 


V'.,..  ■ . 7- . - ry..  i;r>  ..  . 

1 . - ' ' ' “ j 

.,,  .1, ')'!•»'<■  i'U_  y. 

■.  . „7:y7  ' 0 4^  ' ■">  v ‘ ■ ■'*  '*•  ' ; ,-  , ,.  -ry:  .-■,  -r  '•^v.  ■^.  di 


'->,7  ;'':u  >jV 

• : - A',  'iis  ;.  ' ; M-dyU  ' ' i .ri  iB:!;?  ! •,.  r; 

■(^■^■:  -'  ^ . y;?Vi'yWi''3iK4 -'ias.  ■^' 


d .7«.v  ■j'rvi  - ^'.'i 

...  ■ i''',>':7y»(V  4;  . •'?■)■  1 v!,  L .'  . 


.orP  i)#lr;y,7,.:'f'jl/# ’/ * 


'■^'X'^' ^''  Vi’'-'- 


y U.  'A  ■Yf"^-iyxrl  ’,il.-'hi'''  ':  ■ }’  ,<  7:  ■i.'dtii  1 ■ >■ ' ! ' *7?  M ? 7 ■ . ■ i'SJU  , 

• ',•’*'••  ■ * ' .^  - . ' i 


'.'I  ay'?'f;x#d47  i ',’ -^  'j 

■■  ‘ * • . ■ ' i .■'.  ‘ X.*  V-  > w.  .i-li*? 


7 ddv^r.d'f  vivlji'  if',  A' iv ' .I 'f 

■'■'  ■ 7 •■'f^i  ■ i >•■.;  'j7  .iL  -.dyr  ' •:  ..'dn-dl/'f  ‘’fl7  ?.■■  ,')  -IfjiiK* 

-id  ad,y  hJifdiy^.'S'fy  4=>^  ■ .^  iy  ■■;; 'fe)  'y 

v:-7','.  Ai-..  ^\  "/P.  ':'!;  .yf  .ir 'd  ) '■■:  ! .,;’  ^■'►4"?  'ivV'J'-''d:J.i‘tif!'>^j  yd?  ')■>)  ;y.)iiiih%i' 


{sa 


*•  j5.-  •.  ii  V;fli '.' 


»v 


III.  On  the  Ganglia  and  Nerves  of  the  Heart.  By  Robert  Lee,  M.D.,  F.R.S.,  Fellow 
of  the  Royal  College  of  Physicians,  London. 


Received  May  7, — Read  June  7,  1848. 

Haller,  Wrisberg,  Soemmering,  and  other  eminent  anatomists  prior  to  Scarpa, 
have  affirmed  that  no  nerves  are  distributed  to  the  muscular  substance  of  the  heart, 
and  that  its  contractions  do  not  depend  upon  nervous  influence. 

B.  J.  Behrends,  a pupil  of  Soemmering,  in  1792  published  a memoir,  entitled 
“ Dissertatio  qua  demonstratur  Cor  Nervis  carere,”  in  which  it  is  admitted  that 
nerves  accompany  the  coronary  arteries,  and  it  is  distinctly  asserted  that  the  mus- 
cular structure  is  entirely  destitute  of  nerves*. 

The  elaborate  and  splendid  work  of  Scarpa,  ‘‘Tabulae  Neurol ogicae,”  fol.  1794, 
has  for  its  chief  object  the  refutation  of  these  erroneous  views  ; but  before  referring 
to  the  discoveries  of  that  great  authority,  I may  proceed  to  state  that  in  the  mag- 
nificent Plates  of  Mr.  Swan  only  a few  small  branches  of  nerves  have  been  figured, 
which  accompany  the  trunks  of  the  coronary  arteries,  and  the  muscular  substance 
of  the  heart  is  represented  as  almost  completely  destitute  of  nerves. 

M.  Chassaignac,  who  translated  in  1838  Mr.  Swan’s  “Demonstration  of  the 
Nerves  of  the  Human  Body,”  has  repeatedly  denied,  in  the  most  positive  manner, 
that  any  nerves  except  those  which  accompany  the  coronary  arteries  have  yet  been 
demonstrated  in  the  heart.  “ Anatomic  n’a  constatfi  jusqu’a  present,  dans  le  coeur 
que  des  nerfs  arteriels,” — “ I’existence  de  filets  nerveux  independantes  des  vaisseaux 
propres  au  tissu  charnu  est  encore  a demontrer.”  p.  23. 

Scarpa,  however,  had  clearly  delineated  and  described  such  nerves,  viz.  running 
on  the  heart  independently  of,  and  distinct  from  the  coronary  arteries.  . In  the  work 
above  cited,  he  has  given  five  views  of  the  nerves  of  the  human  heart,  in  some  of 
which,  e.  g.  Tab.  IV.,  upwards  of  twenty  filaments  may  be  counted  on  the  same  trans- 
verse line  near  the  base  of  the  heart,  together  with  numerous  anastomotic  angular 
enlargements,  which  Scarpa  does  not  specify  as  ganglions  in  his  text.  In  the  hearts 
of  the  larger  herbivorous  Mammals,  however,  Scarpa  describes  and  delineates  both 
ganglia  and  fusiform  enlargements  of  the  nerves,  which  he  calls  corpora  olivaria,  and 
these  not  only  upon  the  nerves  at  the  base  of  the  heart,  but  upon  those  that  are 
spread  over  the  superficies  of  the  ventricle  : his  words  are,  “ Preecipue  autem  nervo- 
rum cardiacorum  trunci  ad  basim  cordis  et  inter  majora  vasa  arteriosa  intumescant 

* Ac  prime  quidem  nervorum  cordis  examini  scrupulosius  intendens,  turn  observando,  turn  analogice  conclu- 
dendo  didici  nullos  omnino  nervos  ne  surculum  quidem  in  ipsam  cordis  carnem  dispergi. 

G 2 


44 


DR.  LEE  ON  THE  GANGLIA  AND  NERVES  OF  THE  HEART. 


in  vera  et  genuina  ganglia  ; in  Equo  autem  et  Bove  etiam  in  iis  ramis  cardiacorum 
qui  per  cordis  superficiem  reptant  nonnulla  corpora  olivaria  gignunt*.”  In  Tab.  VII. 
fig.  1,  he  represents,  and  at  p.  42  specifies  some  of  these  enlargements;  one,  e.  g. 
marked  7?  as  a “ gangliforrnis  intumescentia  a second,  marked  30,  as  “ cardiaci 
sinistri  ganglion  irisigne.”  Scarpa  also  describes  and  figures  several  nerves  inde- 
pendent of,  and  not  accompanying  the  blood-vessels  of  the  heart,  and  avails  himself 
of  the  fact  to  refute  the  conclusions  to  which  Behrends  had  arrived  in  the  Treatise 
above  quoted. 

The  following  are  the  facts  relative  to  the  nervous  supply  of  the  heart  which  I 
believe  myself  to  have  established  by  examination  of  the  foetal  heart,  of  the  heart  of 
a child  at  the  age  of  six  years,  of  the  heart  of  an  adult  in  a sound  state,  of  the  human 
heart  hypertrophied,  and  of  the  heart  of  the  Ox,  and  which  the  preparations  are  pre- 
served to  demonstrate. 

The  drawing  No.  1,  entitled  “The  nerves  of  the  heart  of  a child  nine  years  of 
age,”  nat.  size,  represents  the  preparation  displaying  the  nerves  distributed  over  the 
exterior  of  the  left  ventricle  which  come  off  from  the  “plexus  coronarius  posticus” 
of  Scarpa 'I',  together  with  a few  filaments  from  the  “plexus  coronarius  anterior,” 
Scarpa.  It  shows  the  ganglions  which  Scarpa  has  delineated  below  the  letters  a 
and  h in  his  Tab.  IV.,  and  also  the  slight  enlargement  at  point  of  confluence  of  three 
or  more  nerves  which  Scarpa  has  likewise  figured,  as  e.  g.  between  the  nerves  num- 
bered 58  and  59,  and  in  several  other  parts  of  the  cardiac  nerves  displayed  in  the 
Tab.  IV.  above  cited.  In  the  place  of  the  long  and  narrow  loop  on  the  nerve  which 
Scarpa  figures  between  the  two  chief  branches  of  the  posterior  coronary  artery,  my 
preparation  shows,  as  in  the  drawing  herewith  sent,  a slender  fusiform  enlargement. 
The  preparation  also  demonstrates  nerves  extending  beyond  the  points  where  they 
end  in  Scarpa’s  figure,  as  far  as  the  apex  of  the  heart ; and  a slight  expansion  and 
flattening  is  presented  by  some  of  these  apicial  filaments  of  nerves,  and  nerves  not 
coincident  in  their  course  with  the  arterial  branches  are  also  shown  in  the  prepara- 
tion which  have  neither  been  described  nor  delineated  by  previous  anatomists. 

In  the  dissection  of  the  sound  heart  of  the  adult,  depicted  in  the  drawing  No.  2, 
entitled  “The  ganglia  and  nerves  at  the  apex  of  the  left  ventricle  of  the  sound 
human  heart,”  the  additional  nerves  at  the  apex  of  the  left  ventricle  are  more  clearly 
shown,  in  which  three  slender  fusiform  enlargements  are  shown  on  nerves  accompa- 
nying the  apicial  branch  of  the  posterior  coronary  artery : there  is  also  a well-marked 
angular  enlargement  at  the  point  of  junction  of  four  nerves  near  a neighbouring 
branch  of  the  artery. 

The  preparation  which  most  distinctly  establishes  the  fact  of  fusiform  enlarge- 
ments of  the  cardiac  nerves,  is  that  represented  in  the  drawing  No.  3,  entitled  “ The 
ganglia  and  nerves  of  the  left  ventricle  of  a Heifer’s  heart  and  cardiac  fascia in 

Op.  cit.  p.  2. 

j Tabulae  Neurologicae,  fol.  1794,  Tab.  IV.  Nos.  45,  46,  47,  48,  6U  and  6i. 


DR.  LEE  ON  THE  GANGLIA  AND  NERVES  OF  THE  HEART. 


45 


which  it  will  be  seen  that  some  of  these  fusiform  ganglionic  enlargements  of  the  car- 
diac nerves  are  nearly  in  the  same  position  as  that  of  the  “ ganglion  insigne,”  de- 
scribed and  figured  by  Scarpa  in  the  heart  of  the  Horse,  Tab.  VII. 

The  ventricles  and  auricles  of  the  human  heart  and  those  of  the  larger  quadrupeds 
are  covered  with  two  distinct  membranes.  The  first  or  exterior  of  these  is  the  serous 
membrane  which  lines  the  pericardium  and  is  reflected  over  the  whole  surface  of  the 
heart ; this  membrane  is  connected  rather  firmly  by  cellular  tissue  with  another  tunic, 
which  has  scarcely  if  at  all  been  noticed  by  anatomists.  This  second  membrane 
has  a dense  fibrous  structure,  is  semitransparent,  and  resembles  in  a striking  manner 
the  aponeurotic  expansions  or  fasciae  covering  muscles  in  other  parts  of  the  body, 
and,  like  them,  sends  numerous  fibres  or  processes  between  the  muscular  fasciculi, 
blood-vessels,  nerves  and  adipose  substance  of  the  heart,  which  it  binds  closely 
together.  This  aponeurotic  expansion  investing  both  ventricles  and  auricles  may  be 
appropriately  termed,  from  its  structure  and  function,  the  fibrous  membrane,  or 
Cardiac  Fascia. 

The  drawings,  which  have  been  executed  by  Mr.  West  with  the  greatest  pains  and 
attention  to  accuracy,  will  supply  the  need  of  special  verbal  description  of  the  nervous 
filaments,  their  anastomotic  enlargements  and  fusiform  swellings ; and  the  series  of  my 
dissections  shows  that  the  nerves  of  the  heart  which  are  distributed  over  its  surface, 
and  throughout  its  walls  to  the  lining  membrane  and  columnae  carneae,  enlarge  with 
the  natural  growth  of  the  heart,  before  birth  and  during  childhood  and  youth,  until 
the  heart  has  attained  its  full  size  in  the  adult ; that  the  nervous  supply  of  the  left 
ventricle  is  greater  than  that  of  the  right ; and  that  when  the  walls  of  the  auricles 
and  ventricles  are  affected  with  hypertrophy,  the  ganglia  and  nerves  of  the  heart  are 
enlarged  like  those  of  the  gravid  uterus. 


Explanation  of  the  Plates. 

PLATE  1. 

Fig.  1 represents  the  great  cardiac  ganglionic  plexus  of  nerves,  situated  between  the 
aorta  and  pulmonary  artery,  which  receives  branches  of  nerves  from  the 
sympathetic,  par  vagum,  and  recurrent  nerves  of  both  sides : and  likewise 
the  ganglia  and  nerves  distributed  over  the  surface  of  the  left  ventrical  of 
the  heart  of  a child  nine  years  of  age.  Natural  size. 

a.  The  arch  of  the  aorta. 

b.  The  pulmonary  artery  truncated  at  its  origin. 

c.  The  anterior  surface  of  the  left  ventricle  of  the  heart. 

d.  The  anterior  surface  of  the  right  ventricle, 

e.  The  left  par  vagum  and  recurrent  nerve. 

f.  The  great  cardiac  ganglionic  plexus  of  nerves  situated  between  the  aorta 

and  pulmonary  artery,  from  which  all  the  principal  cardiac  nerves  are 
derived. 


46 


DR.  LEE  ON  THE  GANGLIA  AND  NERVES  OF  THE  HEART. 


g.  The  ganglionic  plexus  of  nerves  accompanying  and  surrounding  the 

trunk  and  branches  of  the  left  coronary  artery,  and  the  ganglia  and 
nerves  distributed  over  the  muscular  substance  of  the  left  ventricle  to 
the  apex  ; the  serous  membrane  and  cardiac  fascia  having  been 
removed. 

Fig.  2 represents  the  ganglia  and  nerves  at  the  apex  of  the  anterior  surface  of  the 
adult  human  heart  in  the  natural  state,  with  a portion  of  the  cardiac  fascia 
dissected  off  from  the  blood-vessels,  nerves  and  muscular  substance  to 
which  it  firmly  adhered. 

a.  The  branches  of  the  coronary  artery  at  the  apex  of  the  heart  surrounded 
by  ganglia  and  nerves. 

h.  Ganglia  and  nerves  on  the  muscular  substance  af  the  heart  ot  the  apex 

not  accompanying  blood-vessels, 
c.  The  cardiac  fascia. 


PLATE  II. 

Represents  a portion  of  the  cardiac  fascia,  and  the  ganglia  and  nerves  on  the  surface 
of  the  left  ventricle  of  the  Heifer’s  heart. 

a.  A portion  of  the  serous  membrane  dissected  off  from  the  cardiac  fascia. 

b.  The  cardiac  fascia  with  the  numerous  ganglia  and  nerves  seen  through 

it,  undisturbed  by  dissection. 

c.  Branches  of  the  left  coronary  artery,  with  ganglia  on  the  nerves  where 

they  cross  the  blood-vessels. 


J’/aZ.Trans . JCDCCCXLIXl.  jPlate  I.  p.  45 . 


Ti  (f.  /. 


2. 


J’-Masirp  - 


Z.  finest  dA. 


mil.  75-^72^.  :mdcccsl]x.^^z/^  ir.p.  'W. 


«r 


J.Bcbsire  sc . 


€> 


t 

• ‘ 


J! 


t; 


m 


[ 47  ] 


IV.  Postscript  to  a Paper  “ On  the  Ganglia  and  Nerves  of  the  Heart." 
By  Robert  Lee,  M.D.,  F.R.S. 

Received  December  21,  1848, — Read  January  11,  1849. 


Since  the  communication  above  referred  to  was  presented  to  the  Royal  Society, 
I have  made  a very  minute  dissection  in  alcohol  of  the  whole  nervous  system  of  the 
young  heifer’s  heart.  The  distribution  of  the  ganglia  and  nerves  over  the  entire 
surface  of  the  heart,  and  the  relations  of  these  structures  to  the  blood-vessels  and 
muscular  substance,  are  far  more  fully  displayed  in  these  preparations  than  in  any  of 
my  former  dissections.  On  the  anterior  surface,  there  are  distinctly  visible  to  the 
naked  eye  ninety  ganglia  or  ganglionic  enlargements  on  the  nerves,  which  pass 
obliquely  across  the  arteries  and  the  muscular  fibres  of  the  ventricles  from  their  base 
to  the  apex.  These  ganglionic  enlargements  are  observed  on  the  nerves,  not  only 
where  they  are  crossing  the  arteries,  but  where  they  are  ramifying  on  the  muscular 
substance  without  the  blood-vessels. 

On  the  posterior  surface,  tlie  principal  branches  of  the  coronary  arteries  plunge 
into  the  muscular  substance  of  the  heart  near  the  base,  and  many  nerves  with 
ganglia  accompany  them  throughout  the  walls  to  the  lining  membrane  and  columnse 
carnese.  From  the  sudden  disappearance  of  the  chief  branches  of  the  coronary 
arteries  on  the  posterior  surface,  the  nervous  structure  distributed  over  a consider- 
able portion  of  the  left  ventricle  is  completely  isolated  from  the  blood-vessels,  and 
on  these,  numerous  ganglionic  enlargements  are  likewise  observed,  but  smaller  in 
size  than  the  chains  of  ganglia  formed  over  the  blood-vessels  on  the  anterior  surface 
of  the  heart.  In  the  accompanying  beautiful  drawings,  Mr.  West  has  depicted 
with  the  greatest  accuracy  and  minuteness  the  whole  nervous  structures  demon- 
strable in  these  preparations  on  the  surface  of  the  heart.  But  the  ganglia  and 
nerves  represented  in  these  drawings  constitute  only  a small  portion  of  the  nervous 
system  of  the  heart,  numerous  ganglia  being  formed  in  the  walls  of  the  heart  which 
no  artist  can  represent.  It  can  be  clearly  demonstrated  that  every  artery  distributed 
throughout  the  walls  of  the  Uterus  and  Heart,  and  every  muscular  fasciculus  of  these 
organs,  is  supplied  with  nerves  upon  which  ganglia  are  formed. 


48 


DR.  LEE  ON  THE  GANGLIA  AND  NERVES  OF  THE  HEART. 


Explanation  of  the  Plates. 

PLATE  III. 

Exhibits  the  trunk  and  branches  of  the  coronary  arteries,  and  the  ganglia  and 
nerves  distributed  over  the  anterior  surface  of  the  ventricles  of  the  young  Heifer’s 
heart;  the  serous  membrane  and  cardiac  fascia  having  been  wholly  removed. 

PLATE  IV. 

Represents  the  posterior  surface  of  the  same  heart  covered  with  ganglia  and 
nerves,  from  the  base  to  the  apex. 

PLATE  V. 

Represents  the  aorta  and  the  anterior  surface  of  a human  heart  which  was  hyper- 
trophied, and  weighed  four  pounds.  The  trunk  and  some  of  the  branches  of  the  left 
coronary  artery  were  ossified.  The  pulmonary  artery  has  been  cut  away  close  to  the 
right  ventricle.  A portion  of  the  wall  of  the  right  ventricle  has  been  removed  to 
expose  the  cavity  and  the  septum  between  the  ventricles.  The  serous  membrane 
has  been  reflected  off  from  the  cardiac  fascia,  a small  portion  only  of  which  has  been 
left  covering  the  ventricle. 

a.  The  arch  of  the  aorta. 

h.  The  origin  of  the  pulmonary  artery,  which  has  been  completely  removed. 

c.  The  anterior  surface  of  the  left  ventricle. 

d.  The  anterior  surface  of  the  right  ventricle. 

e.  The  great  ganglionic  plexus  of  nerves  into  which  branches  from  the  par 

vagum,  recurrent  and  sympathetic  nerves  of  both  sides  enter,  and  from 
which  the  principal  cardiac  nerves  take  their  origin. 

f.  The  par  vagum  of  the  left  side. 

g.  The  trunk  of  the  left  coronary  artery  ossified  and  completely  surrounded 

with  ganglia  and  nerves,  which  are  distributed  over  the  whole  surface 
of  the  ventricle  to  the  apex. 

h.  The  serous  membrane  reflected  off  from  the  cardiac  fascia,  a small  por- 

tion only  of  which  is  left  covering  the  ganglia  and  nerves  near  the  apex. 

i.  The  cardiac  fascia. 


# 


% 


/'J.WestfM' 


t/.^aswe  .^c. 


i 


I 


>roCCCXLIS.-/7<7^e  LV^/'.  48. 


t..  West  del  ^ 


J.Jiasirc  sc. 


'i-esl.deL'-. 


[ 49  ] 


V.  On  the  Effect  of  surrounding  Media  on  f^oltaic  Ignition. 
By  W.  R.  Grove,  Esq.,  M.A.,  E.P.R.S. 


Received  August  10, — Read  December  14,  1848. 


In  the  Philosophical  Magazine  for  December  1845,  I pointed  out  a striking  differ- 
ence between  the  heat  generated  in  a platinum  wire  by  a voltaic  current,  according 
as  the  wire  is  immersed  in  atmospheric  air  or  in  hydrogen  gas,  and  in  the  Bakerian 
Lecture  for  1847  1 have  given  some  further  experiments  on  this  subject,  in  which  the 
wire  was  ignited  in  atmospheres  of  various  gases,  while  a voltameter  enclosed  in  the 
circuit  yielded  an  amount  of  gas  in  some  inverse  ratio  to  the  heat  developed  in  the 
wire.  It  was  also  shown,  by  a thermometer  placed  at  a given  distance,  that  the 
radiated  heat  was  in  a direct  ratio  with  the  visible  heat. 

Although  the  phenomenon  was  apparently  abnormal,  there  were  many  known  phy- 
sical agencies  by  which  it  might  possibly  be  explained,  such  as  the  different  specific 
heats  of  the  surrounding  media,  their  different  conducting  powers  for  electricity,  or 
the  varying  fluency  or  mobility  of  their  particles  which  would  carry  off  the  heat  by 
molecular  currents  with  different  degrees  of  rapidity. 

The  investigation  of  these  questions  will  form  the  subject  of  this  paper. 

An  apparatus  was  arranged,  see  fig.  1.  Two  glass  tubes  A and  B,  of  0‘3  inch 
internal  diameter  and  1‘5  inch  length,  were  closed  with  corks  at  each  extremity; 
through  the  corks  the  ends  of  copper  wires  penetrated,  and  joining  these  were  coils 
of  fine  platinum  ware,  one-eightieth  of  an  inch  diameter  and  3’7  inches  long  when 
uncoiled.  Tube  A was  filled  with  oxygen,  tube  B with  hydrogen,  and  the  tubes  thus 
prepared  were  immersed  in  two  separate  vessels,  in  all  respects  similar  to  each  other, 
and  containing  each  three  ounces  of  water.  A thermometer  was  placed  in  the  water 
in  each  vessel ; the  copper  wires  were  connected,  so  as  to  form  a continued  circuit, 
with  a nitric  acid  battery  of  eight  cells,  each  plate  exposing  eight  square  inches  of 
surface.  Upon  the  circuit  being  completed  the  wire  in  the  tube  containing  oxygen 
rose  to  a white  heat,  while  that  in  the  hydrogen  was  not  visibly  ignited ; the  tempe- 
rature of  the  water,  which  at  the  commencement  of  the  experiment  was  60°Fahr.  in 
each  vessel,  rose  in  five  minutes  in  the  water  surrounding  the  tube  of  hydrogen  from 
60°  to  70°,  and  in  that  containing  oxygen  from  60°  to  81°*. 

Before  I enter  into  a further  detail  of  experiments,  I would  remark  upon  the  ex- 
traordinary character  of  this  result.  The  same  current  or  quantity  of  electricity 

* After  the  publication  of  the  Bakerian  Lecture,  my  experiment  on  the  peculiar  effect  of  hydrogen  on  the 
ignited  wire  was  noticed  in  a paper  by  M,  Matteucci,  which  though  I had  it  in  my  hand  shortly  after  its 

MDCCCXLIX.  H 


50 


MR.  GROVE  ON  THE  EFFECT  OF 


passes  through  two  similar  portions  of  wire  immersed  in  the  same  quantity  of  liquid, 

Fig.  1. 


and  yet,  in  consequence  of  their  being  surrounded  by  a thin  envelope  of  different 
gases,  a large  portion  of  the  heat  which  is  developed  in  the  one  portion  appears  to 
have  been  annihilated  in  the  other.  Similar  experiments,  varying  the  gas  in  one  tube 
while  hydrogen  was  retained  in  the  other,  gave  the  following  results.  In  five  minutes 
the  thermometer  rose — 

In  the  hydrogen.  In  the  associated  nitrogen. 

1st.  From  60"  to  69°’5.  From  60°  to  81°'5. 


2nd. 

In  hydrogen. 

From  60°  to  70°' o. 

In  carbonic  acid. 

From  60°  to  80°. 

3rd. 

In  hydrogen. 

From  60°  to  70°. 

In  carbonic  oxide. 

From  60°  to  79°‘5. 

4th. 

In  hydrogen. 

From  60°  to  70°‘5. 

In  olefiant  gas. 

From  60°  to  76°\5*. 

On  a different  day  I tried  the  following  experiments ; all  the  circumstances  were 
the  same,  excepting  that  the  battery  was  in  more  energetic  action,  for  which  reason 
I have  not  tabulated  them  with  the  others. 


publication,  I regret  to  say  I did  not  read  with  the  attention  it  deserved.  I have  read  it  since  the  experiments 
in  this  paper  were  commenced,  and  I see  that  I am  now  executing  a task  assigned  to  me  by  ray  friend. 
M.  Matteucci,  for  a different  object,  makes  a somewhat  similar  experiment  to  the  one  given  above,  which 
however  differs  from  mine  in  the  material  point,  that  he  operated  first  on  one  gas  and  then  on  the  other,  and 
thus  did  not  compare  the  effects  produced  by  the  same  quantity  of  electricity.  I cannot  quite  agree  in  the 
conclusions  deduced  by  him  from  this  and  the  other  experiments  he  cites,  but  I will  not  here  contest  them,  as 
it  would  lead  me  away  from  the  main  point  of  this  paper. 

* I should  perhaps  remark,  that  several  test  experiments  were  tried  to  ascertain  the  working  of  the  appa- 
ratus ; thus,  the  same  gas  was  placed  in  both  tubes,  and  the  results  given  by  the  thermometer  were  found  to 
be  accurately  the  same  in  both  vessels.  The  tubes  were  also  changed  with  reference  to  the  containing  vessels 
and  to  the  contained  gases.  The  water  was  always  agitated  to  render  its  temperature  uniform  previously  to 
reading  off,  &c.  &c. 


SURROUNDING  MEDIA  ON  VOLTAIC  IGNITION. 


51 


In  oxygen  associated  with  coal  gas  the  thermometer  rose  in  five  minutes — 

In  oxygen.  In  coal  gas. 

From  60°  to  82°.  From  60°  to  76°. 

In  hydrogen  associated  with  coal  gas  the  thermometer  rose  in  five  minutes — 

In  hydrogen.  In  coal  gas. 

From  60°  to  77°-  From  60°  to  82‘5°. 

From  this  it  would  appear  that  coal  gas  should  be  placed,  as  to  its  cooling  effect  on 
the  ignited  wire,  between  hydrogen  and  olefiant  gas. 

On  another  day  sulphuretted  hydrogen  associated  respectively  with  oxygen  and 
hydrogen  was  tried ; the  wire  in  the  sulphuretted  hydrogen  was  at  first  ignited  to  a 
degree  somewhat  inferior  to  that  in  oxygen,  but  the  gas  was  rapidly  decomposed ; 
sulphur  being  deposited  on  the  interior  of  the  vessel  and  the  intensity  of  ignition  gra- 
dually decreased,  so  as  ultimately  to  be  scarcely  superior  to  the  ignition  in  hydrogen  : 
indeed  the  gas  by  this  time  had  become  nearly  pure  hydrogen.  The  following  were 
the  effects  on  the  thermometer  in  five  minutes,  all  being  arranged  as  before. 

In  oxygen.  In  sulphuretted  hydrogen. 

From  60°  to  86°.  From  60°  to  76°. 


In  hydrogen. 

From  60°  to  79°. 


In  sulphuretted  hydrogen. 

From  60°  to  8l°-5. 


This  result  would  place  sulphuretted  hydrogen  between  hydrogen  and  coal  gas ; 
but  as  the  gas  was  rapidly  decomposed,  the  greater  part  of  the  experiment  was  made 
with  hydrogen  containing  small  quantities  of  sulphur  combined,  and  not  with 
sulphuretted  hydrogen.  I therefore  think  that  proto-sulphuret  of  hydrogen,  or  the 
gas  which  consists  of  equivalent  ratios  of  the  two  elements,  would  be  much  further 
removed  from  pure  hydrogen  ; probably  it  would  be  about  equal  in  its  cooling  effect 
to  carbonic  acid  or  carbonic  oxide. 

In  phosphuretted  hydrogen  the  platinum  wire  is  destroyed  by  combining  with  the 
phosphorus  the  instant  it  reaches  ignition,  so  that  its  relation  to  the  other  gases 
could  not  be  ascertained. 

Protoxide  and  deutoxide  of  nitrogen  are,  as  I have  observed  in  the  Bakerian 
Lecture,  decomposed  by  the  ignited  wire ; they,  as  well  as  atmospheric  air,  are,  as 
nearly  as  may  be,  equal  in  their  effect  to  their  elements  separately. 

In  the  vapour  of  ether  the  ignited  wire  is  extinguished  nearly  as  completely  as  in 
hydrogen  ; I have  not  yet  tried  its  comparative  effect,  but  should  judge  it  to  be  nearly 
the  same  as  coal  gas  or  olefiant  gas. 

In  my  former  experiments*  the  following  was  the  order  of  the  gases,  testing  the 
intensity  of  ignition  by  the  inverse  conducting  power  of  the  wire,  as  measured  by  the 
amount  of  gas  in  a voltameter  included  in  the  circuit. 


* Philosophical  Transactions,  1847,  p.  2. 


52 


MR.  GROVE  ON  THE  EFFECT  OF 


Gases  surrounding  the  wire. 

Hydrogen  . . 

Olefiant  gas 
Carbonic  oxide 
Carbonic  acid  . 
Oxygen  . . . 

Nitrogen  . . 


Cubic  inches  of  gas  evolved  in 
the  voltameter  per  minute. 

...  77 
...  7-0 
...  6-6 
...  6-6 
...  6-5 

...  6-4 


Assuming  that  in  the  present  experiments  the  heat  in  the  water  is  a correct  indica- 
tion of  the  intensity  of  ignition  in  the  wire,  the  order  is  the  same  in  both  series  of 
experiments.  Hydrogen  is  however  so  far  removed  from  both  oxygen  and  nitrogen 
in  its  effects  upon  the  ignited  wire,  that  in  order  more  accurately  to  ascertain  the 
relative  position  of  the  latter  two  gases,  I made  a few  further  experiments  on  them 
as  contrasted  with  each  other,  and  not  with  hydrogen.  I first  repeated  my  former 
experiment  on  these  two  gases,  varying  it  only  by  changing  the  circumstances  in 
the  manner  suggested  by  the  present  experiments,  which  on  account  of  the  vessel 
containing  the  wire  being  immersed  in  a given  quantity  of  water,  instead  of  being 
exposed  to  the  external  atmosphere,  would  occasion  greater  equality  in  the  sur- 
rounding cooling  effects,  and  would  give  me  the  opportunity  of  combining  both 
methods  in  one  experiment. 

I filled  both  tubes  A and  B with  oxygen,  and  included  a voltameter  in  the  circuit ; 
in  two  minutes  3‘43  cubic  inches  of  hydrogen  were  evolved  in  the  voltameter,  and 
the  thermometer  in  each  cell  had  risen  from  60°  to  63°.  A similar  experiment  with 
nitrogen  gave  in  two  minutes  3*4  cubic  inches  of  hydrogen,  and  the  thermometer 
rose  from  60°  to  63°. 

This  experiment  accords  with  my  previous  one  as  to  the  voltameter  test,  but  indi- 
cates no  difference  in  oxygen  and  nitrogen  with  the  thermojueter  test ; I therefore  in 
the  following  three  experiments  associated  nitrogen  with  oxygen  in  the  apparatus, 
fig.  1.  All  things  being  disposed  as  with  the  experiments  on  hydrogen  associated 
with  other  gases,  in  five  minutes  the  thermometer  rose — 


In  the  oxygen. 

Exp.  1st.  From  60°  to  71°'5. 

2nd.  60°  to  77°- 

3rd.  60°  to  75°. 

Mean  . . 60°to74°‘5. 


In  the  associated  nitrogen. 

From  60°  to  73°. 

60°  to  76°. 

60°  to  76°. 

60°  to  75°. 


The  battery  had  increased  somewhat  in  piower  after  the  first  experiment,  but  as 
both  wires  formed  part  of  the  same  circuit  in  each  experiment,  the  variations  in 
battery  power  do  not  affect  the  comparative  results.  The  second  experiment  gives 
a variation  in  the  position  of  oxygen  and  nitrogen  with  reference  to  the  first  and 
third  experiments,  but  the  gases  so  nearly  approach  in  their  cooling  effects,  that 
these  slight  differences  are  not  much  to  be  relied  upon ; however  I applied  a further 


SURROUNDING  MEDIA  ON  VOf/I'AIC  IGNITION. 


5;i 

test.  I associated  in  turn  oxygen  and  nitrogen  with  carbonic  acid;  the  following 
were  the  results.  In  five  minutes  the  thermometer  rose — 

In  oxygen.  In  carbonic  acid. 

Exp.  1st.  From  60°  to  7*5°-  From  60°  to  Jb°. 

2nd.  60°  to  76°.  60°  to  75°. 

In  nitrogen.  In  carbonic  acid. 

Exp.  1st.  From  60°  to  74°.  From  60°  to  73°. 

2nd  60°  to  73°.  60°  to  72°-5. 

The  battery  had  in  the  last  experiment  a little  decreased  in  power  ; the  oxygen  and 
nitrogen  both  produced  a less  cooling  effect  than  the  carbonic  acid,  but  the  oxygen 
came  nearer  to  it  than  the  nitrogen,  thus  according  with  the  previous  experiments. 
Upon  the  whole  it  would  appear  that  oxygen  produces  a somewhat  greater  cooling 
effect  on  the  ignited  wire  than  nitrogen,  but  these  gases  may,  for  the  purposes  of  this 
paper,  be  fairly  regarded  as  equal.  Atmospheric  air  produces  a similar  effect  to 
oxygen  and  nitrogen  separately,  though  I am  inclined  to  think  that  a slight  chemical 
change  takes  place  when  atmospheric  air  is  exposed  to  the  ignited  wire,  and  that 
nitrous  acid  is  formed  ; for  if  litmus  paper  be  held  over  a voltaically  ignited  platinum 
wire  in  the  air,  a slight  but  very  perceptible  tinge  of  red  marks  the  portion  of  it  im- 
mediately over  the  wire. 

With  the  view  of  ascertaining  whether  the  specific  heat  of  the  surrounding  media 
w^ere  the  cause  of  the  phenomenon,  I proceeded  to  try  the  effect  of  the  wire  carrying 
a voltaic  current  on  different  liquids ; all  things  being  disposed  as  in  the  previous 
experiments,  and  three  ounces  of  water  being  associated  respectively  with  the  same 
quantity  of  the  following  liquids.  The  thermometer  I’ose  in  five  minutes — 


In  water,  from  60°  to  70°‘3.  In  spirit  of  turpentine.  60°  to  88°. 


In  water,  from  60°  to  70°' 3. 

In  sulphuret  of  carbon 

60°  to  87°-l. 

In  water,  from  60°  to  69°. 

In  olive  oil  ...  . 

60°  to  85°. 

In  water,  from  60°  to  70°T. 

In  naphtha  .... 

60°  to  78°-8. 

In  water,  from  60°  to  70°’5. 

In  alcohol  sp.  gr.  0’84 

60°  to  77°. 

In  water,  from  60°  to  68°-5. 

In  ether  

60°  to  76°-I. 

I do  not  much  rely  on  the  last  experiment, — the  battery  was  in  more  feeble  action  ; 
and  though  each  of  the  above  results  is  the  mean  of  three  experiments,  yet  the 
variations  in  the  results  of  the  different  experiments  with  ether  being  considerable 
(while  in  the  others  they  were  very  trifling),  lead  me  to  place  no  great  dependence 
on  it.  The  rapidity  of  evaporation  and  the  readiness  of  ebullition  of  the  ether  re- 
quire that  a larger  quantity  should  be  used;  but  as  this  for  the  purpose  of  compa- 
rison would  have  required  all  the  experiments  to  be  repeated  with  different  quantities 


54 


MR.  GROVE  ON  THE  EFFECT  OF 


of  liquid,  I have  not  thought  it  worth  while  to  go  through  the  series  a second  time. 
It  will  be  observed,  that  the  effects  with  the  above  liquids  are  by  no  means  in  direct 
relation  with  their  respective  specific  heats ; but  in  order  to  bring  the  results  of  the 
experiments  with  liquids  into  comparison  with  those  with  gases,  I now  associated  a 
gas  with  a liquid,  viz.  hydrogen  with  water.  All  things  being  disposed  as  before, 
the  tube  A was  filled  with  hydrogen  gas,  the  tube  B with  water,  both  being  immersed 
in  three  ounces  of  water.  The  thermometer  rose  in  five  minutes — 


In  hydrogen. 


From  60°  to  75°-5. 


In  water. 

From  60°  to  72° 


This  experiment  of  itself  conclusively  negatives  the  possibility  of  specific  heat  alone 
accounting  for  the  phenomenon  under  consideration  ; and  though,  doubtless,  specific 
heat  must  have  some  influence  on  the  cooling  effects  of  different  gases  and  liquids, 
yet  in  the  former  it  is  apparently  of  very  trifling  import  in  comparison  with  the  real 
physical  cause  of  the  differences,  whatever  that  may  be. 

Supposing,  as  is  stated  by  Faraday*,  -that  gases  possess  feeble  conducting  powers 
for  voltaic  electricity,  and  supposing  hydrogen,  from  its  close  analogy  in  chemical 
character  to  the  metals,  to  possess  a greater  conducting  power  than  the  other  gases, 
this  would  account  for  its  peculiar  effect  on  the  ignited  wire,  as  a certain  portion  of 
the  current,  instead  of  forcing  its  way  through  the  wire,  would  be  carried  off  by  the 
surrounding  gas.  In  order  to  ascertain  this  I arranged  the  following  experiments. 

1st.  Into  the  closed  end  of  a bent  tube,  fig.  2,  a loop 
of  platinum  wire,  A B,  and  two  separate  platinum 
wires  C D,  were  hermetically  sealed,  the  extremities 
of  the  latter  being  approximated  as  closely  as  pos- 
sible, and  the  interval  between  them  being  close  to 
and  immediately  over  the  apex  of  the  loop.  The  tube 
was  filled  with  hydrogen,  and  the  wire  A B connected 
with  a voltaic  battery  of  sufficient  power  to  raise  it  to 
as  high  a degree  of  ignition  as  it  would  bear  without 
fusion  ; C and  D were  now  connected  with  the  poles 
of  another  battery,  a delicate  galvanometer  being 
interposed  in  the  circuit.  Not  the  slightest  effect  on  the  galvanometer  needle  could 
be  detected,  and  a similar  negative  effect  took  place  when  the  tube  was  filled  with 
atmospheric  air. 

2nd.  Parallel  portions  of  platinum  wire  were  now  arranged  in  close  proximity  (see 
fig.  3.),  and  so  that  each  might  be  ignited  to  a full  incandescence  by  separate  insulated 
batteries.  When  surrounded  by  atmospheres,  both  of  atmospheric  air  and  of  hydro- 
gen and  fully  ignited,  not  the  slightest  conduction  could  be  detected,  across  the 
interval  between  the  wires,  with  ten  cells  of  the  nitric  acid  battery,  and  being  enabled 

* Experimental  Researches,  §§  272,  441  and  444. 


SURROUNDING  MEDIA  ON  VOLTAIC  IGNITION. 


OO 


by  the  kindness  of  Mr.  Gassiot  to  repeat  this  experiment  with  his  battery  of  500 
well-insulated  cells  of  the  nitric  acid  combination,  air  did  not  conduct  when  the 
ignited  wires  were  approximated  to  the-^th  of  an  inch ; on  approaching  them  nearer 
they  came  within  striking  distance,  were  instantly  fused,  and  the  galvanometer  needle, 
which  had  up  to  this  time  been  perfectly  stationary,  was  whirled  rapidly  round, 

I think  I am  entitled  to  conclude  from  Fig.  3. 

this,  that  we  have  no  experimental  evi- 
dence that  matter  in  the  gaseous  state 
conducts  voltaic  electricity ; probably 
gases  do  not  conduct  Franklinic  electricity,  as  the  experiments  which  would  seem 
primd  facie  to  lead  to  that  conclusion,  are  explicable  as  resulting  from  the  disruptive 
discharge. 

In  Faraday’s  experiment  two  wires  were  approximated  in  the  flame  of  a spirit- 
lamp,  and  a slight  conduction  across  the  interval  in  the  flame  was  observed.  This 
conduction  might  have  been  due  to  certain  unconsumed  particles  of  carbon  existing 
in  the  flame,  or  possibly  to  the  flame  itself ; according  to  Dr.  Andrews,  flame,  even 
that  of  pure  hydrogen  gas,  conducts  voltaic  electricity*. 

I now  endeavoured  to  ascertain  whether  any  specific  inductive  effect  of  the  hydrogen 
might  have  an  influence:  parallel  wires  of  platinum  and  parallel  coiled  copper  wires 
were  placed  in  atmospheres  of  hydrogen  and  of  atmospheric  air,  one  of  which  parallel 
wires  conveyed  the  current,  and  the  other  wire  was  connected  with  a delicate  galva- 
nometer. I could  detect  no  difference  in  the  arcs  of  deflection  of  the  needle  at  the 
instant  of  meeting  or  breaking  contact,  whether  the  wires  were  in  atmospheres  of 
hydrogen  or  of  atmospheric  air;  nor  when  parallel  platinum  wires  with  their  sur- 
rounding atmospheres  of  gas  were  immersed  in  a given  quantity  of  water,  could  I 
detect  any  difference  in  the  resulting  heat,  whether  the  current  passed  in  the  same 
or  in  a different  direction  through  each  wire. 

My  next  object  was  to  ascertain  whether,  in  cases  of  ordinary  ignition,  the  same 
apparent  annihilation  of  heat  took  place  in  hydrogen  gas  as  with  voltaic  ignition. 
Two  iron  cylinders  A B,  fig.  4,  each  weighing  390  grains,  were  attached  to  long  iron 
wires  bent  back  in  the  form  shown  in  the  figure.  The 
cylinders  were  placed  together  in  a crucible  of  fine 
sand,  and  the  whole  heated  to  an  uniform  white  heat. 

The  cylinders  were  now  taken  out  of  the  sand,  placed 
at  the  surface  of  equal  portions  of  water  in  the  vessels 
C and  D ; two  inverted  tubes  e,f,  the  one  of  hydrogen, 
the  other  of  atmospheric  air,  were  placed  over  them, 
and  the  whole  quickly  immersed  in  the  water,  and 
retained  by  a little  contrivance,  which  I need  not  par 
ticularize,  in  the  position  shown  in  the  figure.  The 

* Philosophical  Magazine,  vol.  ix.  p.  176. 


Fig.  4. 


56 


MR.  GROVE  ON  THE  EFFECT  OF 


temperature  of  the  water  at  the  commencement  of  the  experiment  was  60°  Fahr. 
In  four  minutes  the  water  surrounding  the  hydrogen  had  risen  to  94°,  and  became 
stationary  there,  while  that  surrounding  the  air  had  only  reached  87°;  in  ten  minutes 
tlie  water  surrounding  the  hydrogen  had  sank  to  92°'5,  while  that  surrounding  the 
air  had  risen  to  93°,  which  was  the  highest  temperature  it  reached  ; thus  the  respective 
maxima  were  94°  and  93°;  but  considering  the  greater  time  which  the  water  sur- 
rounding the  air  required  to  attain  its  maximum  temperature,  and  that  being  during 
this  time  at  a temperature  above  that  of  the  surrounding  atmosphere,  it  must  have 
lost  something  of  its  acquired  heat,  we  may  fairly  consider  the  maxima  to  be  the 
same,  and  that  the  difference  of  effect  in  the  two  gases  had  reference  solely  to  the 
time  occupied  in  the  transference  of  the  heat.  In  a second  experiment  the  results 
were  similar,  the  maximum  being  in  this  experiment  92‘5  in  hydrogen,  and  91 
in  air^'. 

As  far  as  ordinary  ignition  is  concerned,  hydrogen  has  been  shown  by  the  expe- 
riments of  Leslie  and  Daw  to  produce  a more  rapid  cooling  effect  than  air;  and 
the  above  experiment  having  shown  that* it  does  not  alter  or  convert  into  any  other 
force  the  actual  amount  of  heat  given  off,  my  next  step  was  to  inquire  whether  this 
rapidity  of  cooling  effect  of  the  hydrogen  would  account  for  the  effects  observed  with 
voltaic  ignition.  Although  the  two  classes  of  effects  were  apparently  very  different, 
it  might  be  that  the  improved  power  of  conduction  arising  from  the  rapid  cooling 
effect  of  the  hydrogen  might,  by  enabling  the  current  to  pass  more  readily,  carry  off 
the  force  in  the  form  of  electricity,  which  if  the  wire  offered  more  resistance  (as  it 
would  when  more  highly  ignited)  would  be  developed  in  the  form  of  heat.  By  em- 
ploying the  same  medium,  but  impeding  the  circulation  of  the  heated  currents  in  one 
case,  while  their  circulation  was  free  in  the  other,  some  light  might  be  expected  to  be 
thrown  on  the  inverse  relation  of  the  conducting  power  to  the  heat  developed.  The 
following  experiment  was  therefore  tried. 

In  the  apparatus  represented  in  fig.  1,  tube  A was  uncorked,  so  as  to  allow  free 
passage  for  the  water,  while  tube  B was  filled  up  with  fine  sand  soaked  with  water, 
and  then  corked  at  both  ends  ; the  current  was  passed  and  the  following  was  the 
result.  In  the  vessel  containing  tube  A,  the  thermometer  rose  in  five  minutes  from 
52°  to  60°,  and  in  that  containing  tube  B from  52°  to  60°  also ; during  a second  five 
minutes,  the  thermometer  rose  in  the  vessel  containing  A from  60°  to  67°,  and  in  the 
vessel  containing  B from  60°  to  67°  also. 

I tried  another  analogous  experiment : a coil  of  platinum  wire  was  placed  in  a very 
narrow  glass  tube  one-sixth  of  an  inch  diameter  ; this  was  hermetically  sealed  at  one 
end,  and  the  other  drawn  into  a very  narrow  aperture,  little  more  than  sufficient  to 
allow  the  platinum  wire  to  pass,  and  filled  with  water  (it  was  necessary  to  leave  a 
small  aperture  to  prevent  the  bursting  of  the  tube  by  the  expansion  of  the  heated 
water)  ; in  the  other  vessel  a similar  coil  of  platinutn  wire  was  placed,  but  without 

* Iron  wire  produces  a similar  effect  to  platinum  wire  in  the  voltaic  experiments. 


SURROUNDING  MEDIA  ON  VOLTAIC  IGNITION. 


57 


any  glass  tube  at  all.  The  circuit  having  been  completed  as  before,  the  thermometer 
rose  in  five  minutes — 

In  the  water  without  the  tube,  from 60°  to  87°- 

In  the  water  containing  the  tube,  from 60°  to  86°. 

Here  the  difference,  slight  as  it  was,  was  against  what  theory  would  have  led  one  to 
anticipate ; the  exact  equality  however  of  the  previous  experiment,  and  the  close 
approximation  of  the  results  in  this  one,  afford  no  conclusive  information  as  to  the 
point  under  consideration,  though  the  negative  result  rather  tends  against  the  view 
which  would  assimilate  the  effects  of  voltaic  to  those  of  ordinary  ignition. 

As  another  method  of  attaining  the  object  before  mentioned,  viz.  the  inverse  rela- 
tion of  the  conducting  power  of  the  wire  to  the  heat  developed  in  it,  I tried  the 
following  experiment.  A platinum  wire  of  one  foot  long  and  ^th  of  an  inch  dia- 
meter was  ignited  in  air  by  ten  cells  of  the  battery,  a voltameter  being  included  in  the 
circuit ; the  amount  of  hydrogen  given  off  by  the  voltameter  was  one  cubic  inch  in 
forty-four  seconds : half  the  wire  was  now  immersed  in  water  of  the  temperature  of 
60°  Fahr.  ; by  this  means  the  intensity  of  ignition  of  the  other  half  was  notably  in- 
creased ; the  voltameter  now  yielded  one  cubic  inch  in  forty  seconds : two-thirds  of 
the  wire  immersed,  gave  one  cubic  inch  in  thirty-seven  seconds  ; and  five-sixths  im- 
mersed, gave  one  cubic  inch  in  thirty-five  seconds.  The  heat  of  the  portion  of  wire  not 
immersed  in  water  had  in  the  last  experiment  nearly  reaehed  the  point  of  fusion  of  the 
platinum.  By  this  result  it  appears  that  the  increased  resistance  to  conduction  of 
the  ignited  portion  is  not  equal  to  the  increased  conducting  power  of  the  cooled 
portion  of  the  same  wire. 

With  a view  of  seeing  how  far  the  cooling  effect  upon  the  ignited  wire  might  be 
due  to  the  greater  or  less  fluency  or  mobility  of  the  particles  of  the  different  media 
surrounding  it,  I have  looked  into  the  papers  of  Faraday*  and  of  GRAHAM-f-.  In  the 
experiments  of  the  former,  it  appears  that  the  escape  of  different  gases  at  a certain 
pressure  through  capillary  tubes,  or  the  velocities  of  revolution  of  vanes  or  floats 
surrounded  by  different  gases,  was  in  some  inverse  ratio  to  the  density  of  such  gases  ; 
and  the  experiments  of  the  latter  show  that  the  effusion  or  escape  of  gases  through  a 
minute  aperture  in  a plate,  takes  place  with  velocities  inversely  as  the  square  root  of 
their  specific  gravities.  In  Graham’s  experiments,  however,  when  the  escape  took 
place  through  capillary  tubes,  the  results  seemed  subject  to  no  ascertained  law, 
though  the  eompounds  of  carbon  with  hydrogen  passed  through  with  greater  facility 
than  other  gases. 

The  cooling  effects  of  gases  on  the  ignited  wire  are  decidedly  not  in  any  ratio  with 
their  specific  gravities  ; thus,  carbonic  acid  on  the  one  hand,  and  hydrogen  on  the 
other,  produce  greater  cooling  effects  than  atmospheric  air ; and  olefiant  gas,  which 
closely  approximates  air,  and  is  far  removed  from  hydrogen  in  specific  gravity,  much 
more  nearly  approximates  hydrogen,  and  is  far  removed  from  air  in  its  cooling  effect. 

* Quarterly  Journal  of  Science,  vol.  iii.  p.  354.  f Philosophical  Transactions,  1846,  p.  573. 


MDCCCXLIX. 


I 


58 


MR.  GROVE  ON  THE  EFFECT  OF 


Upon  the  whole,  we  may  conclude,  from  the  experiments  detailed  in  this  paper, 
that  the  cooling  effect  of  different  gases,  or  rather  the  difference  in  the  cooling  effect 
of  hydrogen  and  its  compounds  from  that  of  other  gases,  is  not  due  to  differences 
of  specific  heat ; it  is  not  due  to  differences  of  specific  gravity ; it  is  not  due  to  dif- 
ferences of  conducting  powers  for  electricity;  it  is  not  due  to  the  character  of  hydrogen 
in  relation  to  its  transmission  of  sound,  noticed  by  Leslie,  for  reasons  which  I have 
before  given*  ; it  is  not  due  to  the  same  physical  characters  of  mobility  which  occa- 
sion one  gas  to  escape  from  a small  aperture  with  greater  facility  than  another ; but 
it  may  be,  and  probably  is,  affected  by  the  mobile  or  vibratory  character  of  the  particles 
by  which  heat  is  more  rapidly  abstracted.  I at  one  time  thought  that  the  effect  might 
have  relation  to  the  combustible  character  of  the  gas,  and  that  the  electro-negative 
gases  were  in  respect  to  it  contra-distinguished  from  the  electro-positive  or  neutral 
gases,  but  the  experience  I have  obtained  from  the  experiments  detailed  here  induees 
me  to  abandon  that  supposition. 

1 incline  to  think,  that,  although  influenced  by  the  fluency  of  the  gas,  the  pheno- 
menon is  mainly  due  to  a molecular  action  at  the  surfaces  of  the  ignited  body  and  of 
the  gas.  We  know  that  in  the  recognised  effects  of  radiant  heat,  the  physical  state 
of  the  surface  of  the  radiating  or  absorbing  body  exercises  a most  important  influence 
on  the  relative  velocities  of  radiation  or  absorption ; thus,  black  and  white  surfaces 
are,  as  every  one  knows,  strikingly  contra-distinguished  in  this  respect : why  may 
not  the  surface  of  the  gaseous  medium  contiguous  to  the  radiating  substance  ex- 
ercise a reciprocal  influence  ? why  may  not  the  surface  of  hydrogen  be  as  black,  and 
that  of  nitrogen  as  white  to  the  ignited  wire  ? This  notion  seems  to  me  the  more 
worthy  of  consideration  as  it  may  establish  a link  of  continuity  between  the  eooling 
effects  of  different  gaseous  media  and  the  mysterious  effects  of  surface  in  catalytic 
combinations  and  decompositions  by  solids  such  as  platinum.  Epipolic  actions  will, 
I feel  convinced,  gradually  assume  a much  more  important  plaee  in  physics  than 
they  have  hitherto  done ; and  the  further  development  of  them  appears  to  me  the 
most  probable  guide  to  the  connection  by  definite  conceptions  of  physical  and  che- 
mical actions. 

The  difference  of  the  eooling  effect  of  hydrogen,  and  of  those  of  its  compounds, 
where  it  is  not  neutralized  by  a powerful  electro-negative  gas,  from  all  other  gases, 
is  perhaps  the  most  striking  peculiarity  of  the  phenomena  I have  described.  The 
differences  of  effect  of  ail  gases  other  than  hydrogen  and  such  compounds  are  quite 
insignificant  when  compared  with  the  differences  between  the  hydrogenous  and  the 
other  gases.  There  are  some  phenomena  which  I have  before  observed,  and  which 
were,  at  the  time  I noticed  them,  inexplicable  to  me;  but  they  now  appear  depend- 
ent on  this  physical  peculiarity  of  hydrogen.  Thus,  if  a jet  of  oxygen  gas  be  kindled 
in  an  atmosphere  of  carburetted  hydrogen,  the  flame  is  smaller  than  when  the  con- 
verse effect  takes  place.  The  voltaic  arc  between  metallic  terminals  is  also  much 


* Fhiiosophicai  Transactions,  1847. 


SURROUNDING  MEDIA  ON  VOLTAIC  IGNITION. 


59 


smaller  in  hydrogen  gas  than  in  nitrogen,  though  both  these  gases  are  incapable  of 
combining  with  the  terminals  ; indeed  to  obtain  an  arc  at  all  in  hydrogen  is  scarcely 
practicable. 

Davy  has,  in  his  Researches  on  Flame,  given  several  experiments  which  are  similarly 
explicable  ; but  though  noting  the  results,  he  nowhere,  as  far  as  I am  aware,  attri- 
butes them  to  any  specific  peculiarity  of  hydrogen. 

Of  the  phenomenon  which  I have  examined  in  this  paper,  I first  published  an 
account  in  connection  with  some  experiments  on  the  application  of  voltaic  ignition 
to  lighting  mines,  and  it  does  not  appear  impossible  that  the  experiments  now  de- 
tailed may  ultimately  find  some  beneficial  application  in  solving  the  problem  of  a 
safety-light  for  mines.  A light  which  is  just  able  to  support  itself  under  the  cooling 
effect  of  ordinary  atmospheric  air  would  be  extinguished  by  air  mixed  with  hydro- 
genous gas. 

I am  far  from  pretending  to  have  devised  any  means  of  fulfilling  these  conditions, 
and  yet  supplying  an  efficient  light ; I merely  throw  it  out  as  a suggestion  for  con- 
sideration, knowing  that  there  are  no  additions  to  our  knowledge  which  are  not 
ultimately  valuable  in  their  practical  application  ; and  that  a suggestion,  however 
vague, — a new  point  to  those  whose  minds  may  be  occupied  with  the  subject,  may 
lead  them  to  results  which  he  who  makes  the  suggestion  is  unable  to  attain. 


P.S.  Since  this  paper  was  communicated  I have  received  a paper  from  Dr.  Andrews 
of  Belfast,  who  published  as  early  as  1840,  in  the  Proceedings  of  the  Royal  Irish 
Academy,  experiments  similar  to  those  of  mine  first  published  in  1845.  My  expe- 
riments were  made  in  the  same  year  as  those  of  Dr.  Andrews,  but  as  I withheld 
their  publication.  Dr.  Andrews  is  fully  entitled  to  priority.  Had  I known  of  his 
experiments  earlier,  I should  have  recited  them  in  the  first  part  of  this  paper. 


V ■ ^ .-■•■.k  ■'  .n  r^  vitiQ  fli  ';  ’ :■'■>^V^^ 'n^'TITlnj 

■% '^^;F'^‘,rvj)tt(^M''|ji '■'■■a  /’!  •;!!,  iU  07/1  ur;  ^ ,;-‘nr’' 

•'  : ' . ’ ■■:  •■  " .-  ‘^■,  , -.y  ■" 


■p 


1 -, 


' " - ' ■♦•  ' i ^ ' .^  . 


J (f  { r.*-;  iJr?  ' 

'.  .',.  ....  . .,  ' . 
i ' .'.I'trtt* -■  A'i'-  i-:i.  r.  5 


,^i,'>-'ryJ'n't''  •' ' 


7: 

! yu^'{|  VHj:  J|;-Tvr',t»  yiAil  (■■ 

'^'^vwwScmI 

:-i 

fy.  , j. 

! w 'J.- ? 'ttyd  ft}  - r .u  ■ ■ iMiil !> ; . 

■ 

<ui  ■!.'; 

V .'  J . ’-'  ' ’ ’ ■ , - ’ '.*  ' . 

•.  ' . rnri  1 

' ' 'hS— ? ' 

:.  1.  : 


If  rr'- 


• >!  tl!: 


yiJi-  :!. 


■■  « 


' 7>wvi'j  ft  .'j  ;■  r: 

■ ii  ^7  ')f  ■»•«"'  * ■;  • « W . ■,. . . . . . . V ■w.jM 


i 7J:.  .7"?  I \ /y ' './f:*..  .’ii i fo, '<;.■«.•  j'.'l  / . i'..";,  V-. .’»' 


4 


. ! '!  ./.'rii*  , : I-  j; 


I <fn<ihi>SU.r 


V.f  *1.: 


',  ~-T 

f -V  :';;/|:iK 

•">  ;>  ^ 


i±} 


■ '■  ''fi.v-j^.''  *'  V. ;'■•'. 4 •('.tv 


, 

; 'T*. '( 

> ‘ " v''''^i:  .■;, 


y,  ■■  f 


[ 61  ] 


VI.  On  the  Spontaneous  Electrical  Currents  observed  in  the  Wires  of  the  Electric 
Telegraph.  By  W.  H.  Barlow,  Esq.,  M.  Inst.  C.E. 

Communicated  by  Peter  Barlow,  Esq.,  F.R.S. 


Received  May  15, — Read  May  25,  1848. 


The  observations  described  in  the  following  pages  were  undertaken  in  consequence 
of  eertain  spontaneous  deflections  having  been  noticed  in  the  needles  of  the  electric 
telegraph  on  the  Midland  Railway,  the  erection  of  which  was  carried  out  under  my 
superintendence  as  the  Company’s  engineer. 

The  telegraph  is  on  the  principle  patented  by  Professor  Wheatstone  and  Mr.  Cooke, 
and  the  signals  are  given  by  deflecting  a magnetic  needle  suspended  in  a coil  of  fine 
wire,  to  the  right  or  left,  by  means  of  a galvanic  battery. 

Eaeh  wire  has  an  earth  connection  at  its  two  extremities,  and  when  a current  is 
made  to  pass  along  the  wire  by  means  of  the  galvanic  battery,  it  returns  by  the  con- 
ducting power  of  the  earth. 

When  the  telegraph  instruments  are  not  working,  the  batteries  are  put  out  of 
circuit,  and  the  wires  remain  with  a simple  earth  connection  at  both  extremities. 

It  was  in  this  condition  of  the  wires  that  spontaneous  currents  were  observed  to 
arise  in  them,  producing  occasionally  large  deflections  in  the  needles.  These  deflec- 
tions were  sometimes  to  the  right  and  sometimes  to  the  left ; at  times  they  changed 
rapidly  from  right  to  left,  at  others  they  continued  in  one  direction  for  periods  varying 
from  a few  minutes  to  one  or  more  hours. 

The  system  of  telegraphs  which  centres  at  Derby,  consists  of  four  main  lines, 
viz. — 

1st.  From  Derby  in  a southerly  direction  to  Rugby. 

2nd.  From  Derby  to  Birmingham,  which  approaches  a south-westerly  direction. 

3rd.  From  Derby  in  a northerly  direction  to  Leeds. 

4th.  From  Derby  in  a north-easterly  direction  to  Lincoln. 

When  these  four  telegraphs  were  brought  into  operation,  it  was  observed  that  the 
spontaneous  deflections  were  almost  invariably  simultaneous  on  all  the  instruments, 
and  that  when  in  the  Birmingham  telegraph  the  deflection  was  such  as  to  indicate 
that  the  current  was  passing  from  the  telegraph  wires  to  the  earth  at  Derby,  the 
current  in  the  Rugby  wires  was  also  passing  towards  the  earth  at  Derby,  while  the 
two  other  telegraphs  showed  the  current  to  be  passingyrom  the  earth  at  Derby  along 
the  wires  proceeding  in  a northerly  and  north-easterly  direction.  It  was  also  found 
that  when  the  current  took  a reversed  direction  in  one  telegraph,  it  was  reversed  in 


62 


MR.  W.  H.  BARLOW  ON  THE  SPONTANEOUS  ELECTRICAL  CURRENTS 


all.  There  were  some  exceptions  to  this  rule,  but  they  were  rare,  and  always  of 
short  duration. 

The  spontaneous  deflections  of  the  telegraph  needles  had  been  observed  on  other 
lines  of  railway  as  well  as  on  the  Midland,  and  they  had  been  attributed  to  atmo- 
spheric electricity  passing  by  the  wire  through  the  coil  to  the  earth,  or  vice  versa 
from  the  earth  to  the  atmosphere.  This  supposition  was  apparently  strengthened, 
because  during  thunder-storms  it  has  frequently  occurred  that  the  wires  in  the  coils 
have  been  fused,  the  poles  of  the  needles  reversed,  or  the  needles  de-magnetized  ; 
but  it  is  difficult  to  conceive  any  effect  of  atmospheric  electricity  that  would  account 
for  the  relative  positions  of  the  needles  of  the  telegraphs  proceeding  from  Derby 
northwards  as  compared  with  those  proceeding  southwards*. 

My  attention  was  strongly  drawn  to  the  subject  by  the  constancy  of  these  effects, 
when  a circumstance  occurred  which  imparted  a new  interest  to  the  inquiry.  On 
the  evening  of  the  19th  of  March,  1847,  a brilliant  aurora  was  seen,  and  during  the 
whole  time  of  its  remaining  visible,  strong  alternating  deflections  occurred  on  all  the 
instruments.  Similar  effects  were  observed  also  on  the  telegraphs  on  several  other 
lines  of  railway. 

Regarding  with  much  interest  these  effects,  which  appeared  to  open  a new  field  for 
investigation,  I determined  on  making  a systematic  set  of  observations  on  the  subject. 

Each  of  the  lines  of  telegraph  centring  at  Derby  consists  of  several  wires ; from 
Derby  to  Birmingham,  and  Derby  to  Rugby,  there  are  five  wires.  From  Derby  to 
Lincoln  there  are  three  wires,  and  from  Derby  northwards  there  are  seven  wires. 

At  the  time  of  commencing  these  experiments  only  three  wires  had  been  put  in 
operation  for  telegraph  business.  There  were  two  spare  wires  of  the  railway  tele- 
graph from  Rugby  and  Derby,  and  thence  to  Leeds,  unoccupied,  and  two  others  from 
Birmingham  to  Derby  and  from  Derby  to  Normanton  belonging  to  the  Telegraph 
Company,  and  intended  to  form  a portion  of  the  commercial  telegraph,  which  were 
also  at  liberty. 

I applied  to  Mr.  Hatcher,  the  engineer  of  the  Telegraph  Company,  for  permission 
to  make  use  of  their  spare  wires  in  the  proposed  experiments,  which  was  freely 
accorded ; and  I am  much  indebted  to  this  gentleman  and  to  Mr.  Culley,  under 
whose  management  the  Midland  districts  is  placed,  for  the  valuable  assistance  and 
information  they  have  afforded  me  in  this  inquiry. 

My  first  object  was  to  make  two  delicate  galvanometers,  which  was  readily  accom  - 
plished by  making  use  of  the  “ detectors”  employed  in  ascertaining  any  defect  in  the 
insulation  of  the  wires. 

These  instruments  are  similar  in  principle  to  those  employed  in  working  the  tele- 
graph, having  a coil  of  fine  wire  about  1000  feet  in  length,  in  which  an  astatic  needle 

* Since  this  was  written  I have  received  a communication  from  Mr.  Culley,  in  which  he  points  out  an  im- 
portant distinction  between  the  effects  of  lightning  and  the  aurora  on  the  instruments  of  the  telegraph  needles, 
which  I beg  to  add  as  a postscript  to  this  paper. 


>CrT>N*U;HT 


3 AM. 


<iANL 


Mav 


>[av 


Mav  28. 


DIAGRAM  1 


MU'Miin’r 


OBSERVED  IN  THE  WIRES  OF  THE  ELECTRIC  TELEGRAPH. 


63 


is  suspended,  of  which  the  lower  end  is  made  to  preponderate,  so  that  the  natural 
position  of  the  needle  is  vertical.  The  only  alteration  made  to  adapt  this  instrument 
to  the  purpose  was  supporting  the  needles  on  knife  edges  instead  of  circular  bearings, 
and  diminishing  the  gravitating  preponderance  of  the  lower  end  of  the  needles,  which 
alterations  increased  the  sensitiveness  in  a high  degree. 

The  preliminary  experiments  were  directed  towards  ascertaining  whether  the  de- 
flections were  attributable  to  the  electricity  passing  from  the  atmosphere  along  the 
wire  to  the  earth.  The  observations  were  frequently  repeated  on  wires  from  forty 
to  fifty  miles  in  length,  and  their  results  may  be  briefly  stated  as  follows: — 

Wires  insulated  from  the  earth  throughout  their  entire  length  produced  no  deflec- 
tion in  either  instruments. 

Wires  having  an  earth  connection  only  at  one  extremity  produced  no  deflection, 

A complete  circuit  made  by  uniting  both  extremities  of  two  wires,  each  forty-one 
miles  long,  and  insulated  from  the  earth  throughout  their  length,  produced  no  de- 
flection. 

But  in  every  case  deflections  were  obtained  from  a wire  having  an  earth  connec- 
tion at  both  extremities. 

Two  wires  having  earth  connections  at  both  extremities  produced  a larger  deflec- 
tion than  one  wire. 

A later  experiment  on  the  same  subject  showed  that  a wire  having  an  earth  con- 
nection at  one  extremity,  and  another  earth  connection  near  the  middle  of  its  length, 
gave  a deflection  on  the  part  of  the  wire  between  the  two  earth  connections,  but 
none  on  the  part  beyond. 

In  watching  the  operations  of  the  galvanometers  when  in  circuit  with  a wire  having 
two  earth  connections,  it  was  observed  that  the  needle  was  rarely  found  to  remain 
in  the  same  position  many  minutes,  large  variations  taking  place  sometimes  in  a few 
seconds,  and  it  became  interesting  to  ascertain  if  these  changes  coincided  at  both 
ends  of  the  wire. 

In  order  to  submit  this  to  experiment,  simultaneous  observations  were  made  at 
intervals  of  five  minutes  for  twenty-four  hours  on  two  galvanometers,  one  at  Derby 
and  the  other  at  Birmingham,  each  connected  to  the  same  wire. 

Mr.  CuLLEY  took  the  observations  at  Birmingham,  while  I took  those  at  Derby, 
each  being  assisted  by  an  intelligent  telegraph  clerk.  In  addition  to  the  galvano- 
meters, the  wet  and  dry  thermometers  were  also  noted  at  every  observation. 

The  results  of  these  observations  are  given  in  diagram  No.  1,  and  allowing  for  the 
differenee  in  delicacy  of  the  two  galvanometers,  there  is  enough  to  show  that  the 
currents  were  simultaneous  in  all  their  changes ; it  was  also  evident  from  this  experi- 
ment that  the  direction  of  the  current  was  the  same  at  both  extremities  of  the  wire. 

This  fact,  together  with  those  previously  mentioned,  indicates  that  the  currents 
which  produce  deflections  do  not  arise  from  the  transit  of  electricity  between  the 
atmosphere  and  the  earth,  but  that  from  whatever  cause  the  currents  originate,  they 


64 


MR.  W.  H.  BARLOW  ON  THE  SPONTANEOUS  ELECTRICAL  CURRENTS 


travel  along  the  wires  from  one  earth  connection  to  the  other,  alternating  first  in  one 
direction  and  then  in  the  other. 

In  examining  the  results  obtained  from  this  experiment,  there  appeared  a general 
movement  of  the  needle  to  the  right  from  the  commencement  of  the  observations  in 
the  morning  until  midnight,  then  changing  over  to  the  left  until  nine  or  ten  o’clock 
in  the  morning,  when  it  again  passed  to  the  right,  large  and  rapidly  alternating  deflec- 
tions having  occurred  during  the  night,  the  effects  of  which  were  visible  on  the  ordi- 
nary telegraph  instruments.  The  general  direction  of  the  needle,  however,  indepen- 
dently of  these  irregular  influences,  appearing  to  exhibit  some  regularity,  I followed 
up  the  experiments  with  the  galvanometer  at  Derby,  and  found  that  a similar  motion 
of  the  needle  occurred  daily. 

This  discovery  led  me  to  establish  a series  of  observations  for  fourteen  days  and 
nights,  on  two  wires  simultaneously,  one  from  Derby  to  Birmingham,  and  the  other 
from  Derby  to  Rugby,  the  position  of  the  needle  being  recorded  every  five  minutes, 
day  and  night.  The  mean  position  of  the  needles  during  each  hour,  as  obtained 
from  these  observations,  is  given  in  Tables  Nos.  I.  and  II.,  and  the  mean  result  for 
each  week  is  given  in  the  right-hand  column. 

The  path  described  by  the  two  needles  during  the  week,  ending  May  29,  1847,  is 
also  exhibited  in  the  diagram  No.  2. 

In  order  to  explain  the  directions  in  which  the  currents  traversed  the  wires  in  these 
experiments,  it  is  necessary  to  state  that  the  two  extremities  of  the  coil  in  the  galva- 
nometers are  attached  to  two  brass  screw  pegs,  technically  called  ‘‘terminals,”  which 
stand  up  on  the  top  of  the  case  of  the  galvanometer,  one  on  the  left  hand  and  the 
other  on  the  right,  and  the  coil  was  so  arranged  that  when  the  copper  pole  of  a 
battery  was  connected  with  the  left  hand  terminal,  and  the  zinc  pole  with  the  right, 
the  deflection  (which  in  all  cases  refers  to  the  upper  end  of  the  needle)  was  to  the 
left ; and  assuming  that  the  cui  rent  flows  from  the  copper  to  the  zinc  pole,  a deflec- 
tion to  the  left  in  these  observations  indicates  a current  flowing  along  the  wire 
towards  Derby,  and  a right-hand  deflection  shows  the  current  to  be  flowing  from 
Derby  to  the  extremity  of  the  wire. 

In  addition  to  the  above-mentioned  experiments,  simultaneous  observations  were 
made  with  galvanometers  on  the  wires  proceeding  from  Derby  northward  and  south- 
ward, the  results  of  which  showed  that  the  currents  producing  the  regular  diurnal 
deflections  followed  the  same  law  as  to  their  relative  directions  in  the  four  different 
lines  of  telegraph  centring  at  Derby,  as  that  which  had  been  observed  on  the  tele- 
graph instruments  during  periods  of  the  large  spontaneous  deflections. 

The  broad  feature  elicited  by  these  observations  may  therefore  be  stated  to  be, — 

1st.  That  the  path  described  by  the  needle  consisted  of  a regular  diurnal  motion, 
subject  to  disturbances  of  greater  or  less  magnitude. 

2nd.  That  this  motion  is  due  to  electric  currents  passing  from  the  northern  to  the 
southern  extremities  of  the  telegraph  wires,  and  returning  in  the  opposite  direction. 


I’/iz/..  Trans.  l{DCCCXnX.T/n/r\ll^.  A>. 


Ma'sr  J.  1847. 

J.Baszre  sc. 


BIAGRAM  A 


'/•  / 


>v . 


'V 


f .i^r  '1 


4 


ft  t 


f '! 


■ -.1 


/V-//  MUaCXLIX  /Vu/r\m 


XOOX 


NOON 


6PM 


DIAGRAM  A"  3 


OBSERVED  IN  THE  WIRES  OF  THE  ELECTRIC  TELEGRAPH. 


65 


3rd.  That  exclusive  of  the  irregular  disturbances  the  currents  flowed  in  a southerly- 
direction  from  about  eight  or  nine  a.m.  until  the  evening,  and  in  a northerly  direction 
during  the  remainder  of  the  twenty-four  hours. 

The  next  experiments  were  made  with  a view  to  ascertain  if  any  immediate  rela- 
tion existed  between  the  motion  of  the  galvanometers  and  the  daily  variation  of  the 
horizontal  magnetic  needle. 

For  this  purpose  I caused  a temporary  observatory  to  be  erected  in  my  garden  at 
Derby  (about  a mile  from  the  railway  station,  where  the  galvanometer  experiments 
were  made),  and  furnished  it  with  a very  delicate  declinometer. 

On  making  observations  with  the  two  instruments,  it  became  evident  that,  although 
generally  that  part  of  the  day  in  which  the  currents  flow  southwards  (that  is,  from 
eight  or  nine  a.m.  until  the  evening)  the  variation  of  the  horizontal  magnetic  needle  is 
westerly,  and  that  during  the  night  and  early  part  of  the  morning  (at  which  time  the 
currents  travel  northwards)  the  variation  is  easterly;  yet  simultaneous  observations 
showed  no  similarity  in  the  path  described  by  the  magnetic  needle  and  the  galva- 
nometer. 

It  had  however  been  mentioned  by  Colonel  Sabine,  when  my  former  paper  on  this 
subject  was  read,  which  described  large  deflections  having  occurred  on  the  evening 
of  the  19th  of  March,  1847,  that  unusual  disturbances  had  been  observed  at  the  same 
time  in  the  magnetic  needle  not  only  in  England  but  abroad ; I therefore  waited  for 
an  opportunity  to  repeat  the  experiments  with  the  declinometer  at  a time  when  the 
telegraph  needles  were  unusually  deflected. 

On  the  24th  of  September  1847,  I was  enabled  partially  to  carry  out  this  inten- 
tion ; and  on  the  27th  I obtained  a set  of  simultaneous  observations  on  the  galvano- 
meter and  the  magnetic  needle,  the  galvanometer  being  attached  to  a wire  having 
its  earth  connections  at  Derby  and  Rugby. 

These  observations  show  unusual  disturbances  on  both  instruments  on  the  days 
mentioned,  particularly  on  the  24th,  when  it  was  excessive. 

From  communications  I have  been  favoured  with,  it  appears  that  the  deflections 
of  the  telegraph  needles  on  the  24th  of  September  were  general  throughout  the 
kingdom.  They  were  observed  on  the  South  Devon  line  and  in  Scotland,  as  well 
as  on  all  the  lines  in  this  part  of  the  country  ; and  it  is  worthy  of  remark,  that  all  the 
reports  of  the  telegraph  clerks  agree  nearly  in  the  time  of  the  commencement  of  the 
disturbance,  the  earliest  time  stated  being  1T35  a.m.,  and  the  latest  noon. 

The  23rd  of  October  was  another  day  of  strong  deflections,  and  a partial  register 
was  kept  of  them  in  London  by  Mr.  Hatcher.  They  were  equally  strong  on  the 
Midland  line,  and  I have  accounts  of  them  as  far  as  Newcastle.  The  24th  being 
Sunday,  there  was  no  register  kept ; but  they  continued  on  the  25th,  and  were  again 
registered  by  Mr.  Hatcher  in  London,  who  has  favoured  me  with  his  observations ; 
but  beyond  the  fact  of  the  unusual  disturbance,  they  throw  no  additional  light  on 
this  subject. 


MDCCCXLIX. 


K 


6G 


MR.  W.  H.  BARLOW  ON  THE  SPONTANEOUS  ELECTRICAL  CURRENTS 


I have  no  magnetic  observations  on  the  23rd,  24th,  or  25th  of  October,  but  I have 
since  learnt  that  an  unusual  magnetic  disturbance  occurred  on  these  days,  and  there 
appears  no  doubt  of  the  coincidence  of  these  great  disturbances  in  both  instruments. 

On  the  three  occasions  mentioned,  namely,  the  19th  of  March,  the  24th  and  25th 
of  September,  and  the  23rd,  24th  and  25th  of  October,  aurora  was  visible;  and  in 
every  case  which  has  come  under  my  observation,  the  telegraph  needles  have  been 
deflected  whenever  aurora  has  been  visible. 

It  only  remains  now  to  describe  the  experiments  made  to  ascertain  the  line  of 
direction  in  which  the  currents  alternate,  and  it  will  serve  to  render  this  part  of  the 
subject  more  clear,  to  state  in  this  place  that,  from  numerous  experiments,  it  appears 
that  from  whatever  cause  the  currents  are  produced,  the  direction  of  the  current  at 
a given  time  in  any  wire  depends  on  the  relative  positions  of  the  earth  connections, 
if  the  insulation  is  good,  however  circuitous  may  be  the  route  of  the  wire  itself.  For 
example,  the  telegraph  from  Derby  to  Rugby,  forty-nine  miles  in  length,  proceeds 
for  ten  miles  about  S.E.  by  E.  to  Kegworth  ; then  for  nineteen  miles  it  takes  a S.E. 
direction  to  Leicester,  and  the  remaining  twenty  miles  to  Rugby  is  about  S.S.W. 

Having  one  earth  connection  at  Derby,  if  the  other  be  made  at  Rugby,  the  bearing 
of  which  place  from  Derby  is  S.  15°  E. ; the  deflections  accord  with  those  of  the  wire 
to  Birmingham,  bearing  S.  29°  W. ; but  if  the  earth  connection  of  the  Rugby  wire  be 
changed  from  Rugby  to  Kegworth,  the  bearing  of  which  from  Derby  is  S.  62°  E.,  the 
deflections  produced  are  in  the  contrary  direction  to  those  of  the  Birmingham  Mure. 

I do  not  consider  that  this  fact  in  itself  proves  that  the  currents  are  generated  in 
the  earth,  for  they  might  arise  from  other  causes,  and  yet  exhibit  the  same  result. 
I only  mention  the  fact  in  this  place  to  facilitate  the  consideration  of  the  direction 
in  which  the  cui’rents  alternate,  and  to  indicate  that  when  the  direction  of  the  cur- 
rent between  any  two  places  is  described,  it  is  not  meant  that  the  wire  is  laid  in  a 
direct  line  between  the  two  points,  but  that  the  earth  connections  are  so  placed. 

Referring  the  direction  of  deflection  in  every  case  to  those  produced  by  the 
Birmingham  wire,  and  denoting  those  which  accord  with  it  by  the  sign  -|-,  and  those 
which  exhibit  a contrary  deflection  — , the  results  of  the  experiments  on  direction 
were  as  follows  : — 


Derby  to  Willington,  bearing  . 
Derby  to  Birmingham,  bearing  . 
Derby  to  Rugby,  bearing  . . . 

Derby  to  Leicester,  bearing  . . 


S.W.  H- 
S.  29°  W.  + 
S.  15°  E.  + 


Derby  to  Loughborough,  bearing 
Derby  to  Kegworth,  bearing 


S.  38°  E.  -f-  - 
S.  50°  E.  doubtful. 


Derby  to  Nottingham,  bearing  . 
Derby  to  Lincoln,  bearing  . . 

Derby  to  Chesterfield,  bearing  . 
Derby  to  Normanton,  bearing  . 


S.  62°  E.  — 
N.  80°  E.  - 
N.  60°  E.  — 
N.  5°  E.  - 

30  _ 


OBSERVED  IN  THE  WIRES  OF  THE  ELECTRIC  TELEGRAPH. 


67 


The  observ’ations  were  made  with  galvanometers  on  two  or  more  wires  simulta- 
neously, and  the  motions  of  the  needles  observed  for  several  hours.  It  frequently 
happens  that,  from  some  difference  in  the  earth  connection,  there  is  a slight  perma- 
nent action,  so  that  in  making  these  observations  it  is  not  simply  the  position  but 
the  motion  of  the  needles  that  distinguishes  the  direction  of  the  current.  If  on  try- 
ing two  wires,  one  causes  the  galvanometer  needle  to  move  from  right  to  left,  when 
the  other  moves  from  left  to  right,  the  currents  are  in  opposite  directions. 

Mr.  CuLLEY  has  favoured  me  with  another  set  of  observations  obtained  from  the 
telegraph  instruments  at  Normanton,  during  large  deflections. 

Normanton  is  a central  station  from  which  seven  telegraphs  branch  off.  Each 
telegraph  has  an  earth  connection  at  Normanton,  and  the  other  extremities  of  the 
telegraphs  are  connected  with  the  earth  at  Rugby,  Derby,  Manchester,  Leeds,  New- 
castle, York  and  Hull. 

Calling  those  telegraphs  in  which  the  deflections  accord  with  that  to  Manchester 
-f,  the  results  are  as  follows  ; — 

From  Normanton  to  Rugby.  . . S.  5°  E.  + 

From  Normanton  to  Derby  . . . S.  2°  W.  -f- 

From  Normanton  to  Manchester  . S.  65®  W.  -j- 

From  Normanton  to  Leeds  . . . N.  35°  W.  doubtful  — , very  small  deflections. 

From  Normanton  to  Newcastle  . N.  8°  W.  doubtful,  generally  — . 

From  Normanton  to  York  . . . N.  40°  E.  — 

From  Normanton  to  Hull  . . . N.  87°  E.  — 

The  general  result  derived  from  these  two  sets  of  experiments  may  be  stated  as 
follows ; — Taking  one  earth  connection  as  a point  of  reference  when  the  bearing  of 
the  other  earth  connection  lies  between  S.  and  W.,  or  between  N.  and  E.,  the  action 
is  strong  and  decided,  the  one  being  -f-  and  the  other  — . 

In  the  experiments  made  from  Derby  as  a central  point,  the  action  of  the  current 
is  reversed  when  the  earth  connection  is  changed  from  S.  15°  E.  to  S.  62°  E.  I have 
tried  numerous  experiments  between  these  two  directions,  and  there  does  not  appear 
to  be  any  line  in  which  all  action  ceases,  but  in  approaching  the  S.E.  direction  the 
motion  of  the  needles  becomes  undefined. 

The  direction  in  which  the  currents  travel  being  supposed  to  be  at  right  angles  to 
that  in  which  the  reversed  action  takes  place,  will  be  between  S.  28°  W.  and  S.  76°  W., 
and  apparently  strongest  when  the  earth  connections  are  about  N.E.  and  S.W. 

As  the  fact  above  mentioned,  namely,  that  the  direction  of  the  current  in  any  wire 
at  a given  time  depends  on  the  relative  positions  of  the  earth  connections,  and  not 
on  the  direction  of  the  wire  itself,  is  of  great  interest,  I have  recently  repeated  some 
of  the  observations  on  this  subject,  the  results  of  which  are  given  in  diagram  No.  3. 

In  these  observations,  a spare  wire  from  Derby  to  Willington,  length  6^  miles, 
bearing  S.W.,  was  used  as  a standard  of  comparison,  and  simultaneous  observations 
were  made  on  it,  and  on  a wire  from  Derby  to  Rugby,  varying  the  position  of  one  of 
the  earth  connections  of  the  Rugby  wire  as  described  below. 


68 


MR.  W.  H.  BARLOW  ON  THE  SPONTANEOUS  ELECTRICAL  CURRENTS 


First  Day's  Ohservations^  May  \st,  1848. 

The  positions  of  the  earth  connection  were, — 

No.  1 wire.  Derby  and  Willington,  bearing  S.W. 

No.  2 wire.  Derby  and  Rugby,  bearing  S.  15°  E. 

The  path  described  by  the  two  galvanometer  needles  is  shown  in  figs.  1 and  2,  and 
it  will  be  seen  that  there  is  an  obvious  similitude  throughout  all  their  movements. 

Second  Days  Observations,  May  3rd,  1848. 

The  position  of  the  earth  connections  were, — 

No.  1 wire.  Derby  and  Willington,  bearing  S.W. 

No.  2 wire.  Derby  and  Leicester,  bearing  S.  38°  E. 

The  movement  of  the  galvanometers  is  shown  at  figs.  3 and  4.  There  is  a partial 
similarity  in  the  forenoon,  but  none*  afterwards. 

Third  Days  Observations,  May  bth,  1848. 

Earth  connections  the  same  as  in  the  last  experiment. 

The  paths  of  the  galvanometers  is  shown  at  figs.  5 and  6.  There  is  no  similarity 
in  the  movement  of  the  needles,  excepting  that  the  general  march  of  both  needles  is 
from  the  left  in  the  morning,  towards  the  right  in  the  afternoon. 

Fourth  Days  Observations,  May  3th,  1848. 

The  position  of  the  earth  connections  were, — 

No.  1 wire.  Derby  and  Willington,  bearing  S.W. 

No.  2 wire.  Derby  and  Kegworth,  bearing  S.  62°  E. 

The  movement  of  the  needles  is  shown  at  figs.  7 and  8. 

In  this  case  we  have  a contrary  direction  of  the  current  clearly  marked  and  ren- 
dered more  evident  by  the  larger  deflections  which  occurred  on  this  day. 

These  experiments  are  satisfactory  as  verifying  the  former  observations  made  on 
this  subject  from  time  to  time  during  the  last  twelve  months. 

It  should  be  mentioned  that  no  part  of  the  Rugby  wire  was  disconnected  in  these 
experiments,  but  that  the  whole  length  of  wire  was  in  action,  and  therefore  exposed 
to  the  same  influences  from  atmospheric  currents,  induction,  or  thermo-electric 
action.  There  was  no  alteration  whatever  made  in  the  wire  excepting  the  change  of 
position  of  one  of  its  earth  connections',  and  consequently  the  reversing  of  the  direc- 
tion of  the  current  in  the  wire,  as  compared  with  that  of  the  Willington  wire,  cannot 
be  attributed  to  any  other  cause. 

The  question  naturally  presents  itself,  from  whence  do  these  currents  arise  ? 

On  this  subject  an  important  fact  was  ascertained  during  the  large  deflections 
which  occurred  in  September  and  October,  namely,  that  spontaneous  deflections  of 


OBSERVED  IN  THE  WIRES  OF  THE  ELECTRIC  TELEGRAPH. 


69 


precisely  the  same  character  as  those  described  in  the  foregoing  part  of  this  paper, 
were  found  to  take  place  on  the  short  telegraph  from  the  Electric  Telegraph  office  in 
the  Strand  to  the  Nine  Elms  Station,  the  wires  of  which  are  laid  underground  in 
tubes  throughout  their  length. 

Taking  this  fact  in  connection  with  those  before  mentioned,  viz.  that  no  deflection 
is  produced  in  a wire  suspended  throughout  its  length  in  the  air,  that  no  deflection 
is  produced  with  a wire  having  only  one  earth  connection,  but  that  in  every  case 
deflections  are  exhibited  in  a vdre  having  two  earth  connections,  and  that  the  direc- 
tion of  the  current  in  the  wire  at  any  given  time  is  dependent  on  the  relative  positions 
of  the  earth  connections,  the  most  probable  explanation  appears  to  be  that  the  cur- 
rents are  terrestrial,  of  which  a portion  is  conveyed  along  the  wire,  and  rendered 
visible  by  the  multiplying  action  of  the  coil  of  the  galvanometer. 


POSTSCRIPT. 

{Copy.) 

My  dear  Sir,  Derby,  May  8,  1848. 

It  has  often  occurred  to  me,  that  if  the  deflections  were  caused  by  atmospheric 
electricity,  they  should  occur  before  and  during  storms.  I have  never  observed  this 
to  have  been  the  case  ; the  needles  are  seldom  moved  by  lightning,  and  if  they  are, 
it  is  in  spasmodic  twitchings,  perfectly  different  to  the  most  rapidly  varying  deflec- 
tions ; but  the  bells  are  generally  rung  if  a storm  occur  at  any  point  of  their  circuit; 
on  the  other  hand,  deflections,  unless  exceedingly  powerful,  do  not  ring  the  bells. 

A marked  difference  is  always  observed  in  the  effect  on  the  bells,  between  light- 
ning and  deflections,  the  first  causing  them  to  ring  only  a second,  the  last  for  several 
minutes. 

I have  twice  this  winter  foretold  an  aurora  ; the  connection  between  this  pheno- 
menon and  the  deflections  is  indisputable. 

In  the  great  storm  at  Leeds,  Huddersfield,  and  the  neighbourhood,  of  a few  Sun- 
days since,  I had  four  pair  of  needles  demagnetised  at  Normanton,  one  at  Skipton, 
and  a discharge  between  the  points  of  the  conductors  at  Bradford.  The  wires  were 
disconnected  from  the  instruments  for  safety,  and  a discharge  took  place  from  the 
free  ends ; still  the  needles  were  not  deflected  in  the  least  degree,  either  before  or 
after  the  storm,  nor  at  any  time  when  the  instruments  were  in  circuit  during  its 
continuance. 

I had  an  excellent  opportunity  at  Normanton  last  Monday  of  testing  the  direction 
of  the  line  of  “ no-action.” 

The  Manchester  and  the  Derby  instruments  were  each  strongly  deflected.  I opened 
the  circuit  on  one  needle  from  Manchester  to  Derby,  leaving  the  other  needles  on 


70  MR.  W.  H.  BARLOW  ON  THE  SPONTANEOUS  ELECTRICAL  CURRENTS 

the  earth  at  Normanton  as  usual.  The  deflections  continued  as  before  on  the  circuit 
from  Derby  to  Normanton,  and  Manchester  to  Normanton,  but  disappeared  on  the 
Derby  to  Manchester  circuit,  these  places  lying  nearly  in  the  line  of  “ no-action,”  as 
determined  by  your  experiments. 

I find  the  line  from  London  to  Derby  but  slightly  affected,  and  that  from  Norman- 
ton to  Leeds  is  almost  entirely  free. 

I am,  my  dear  Sir,  yours  very  truly, 

{Signed)  R.  S.  Gulley. 


W.  H.  Barlow,  Esq.,  Derby. 


OBSERVED  IN  THE  WIRES  OF  THE  ELECTRIC  TELEGRAPH 


71 


Table  I. 

Mean  deflections  in  each  hour  exhibited  by  a galvanometer  at  Derby,  in  connection 
with  a wire  extending  to  Rugby,  for  fourteen  days,  commencing  May  17,  1848. 
(The  means  are  taken  from  twelve  observations  in  each  hour.) 


Rugby  Instrument. 


Time. 

May  17. 

May  18. 

May  19. 

May  20. 

May  21. 

May  22. 

May  23. 

Mean. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

1 A.M. 

2-42 

3-92 

2-71 

4-12 

0-14 

0-61 

2 

6-29 

5-37 

3-87 

2-21 

0-50 

3-65 

3 

4-'50 

5-87 

1-42 

3-87 

0-71 

0-91 

4 

2-50 

3-60 

« . • 

2-60 

1-17 

0-40 

0-38 

5 

1-83 

1-75 

1-58 

6-83 

0-71 

6 

1-50 

0-'25 

0-92 

2-83 

0-62 

7 

6-’45 

2-25 

0-21 

2-00 

1-12 

8 

3-09 

6-83 

6-66 

3-66 

3-56 

9 

5-66 

2-17 

1-87 

6-87 

2-21 

10 

4-16 

308 

1-46 

0-33 

3-75 

0-76 

11 

.... 

0-42 

2-50 

2-00 

3-69 

5-33 

2-50 

12  Noon. 

3-17 

5-08 

3-25 

... 

1-62 

508 

3-64 

1 P.M. 

5-17 

2-25 

1-79 

4-71 

2-42 

2-37 

2 

9-75 

2-42 

3-64 

6-'32 

1-08 

3-31 

3 

7-08 

0-33 

0-66 

2-17 

1-05 

1-99 

4 

9-ii 

9-60 

0-46 

d’so 

... 

2-54 

1-29 

4-58 

5 

7-12 

6-20 

6-25 

0-62 

2-12 

4-46 

6 

10-82 

11-33 

205 

3-46 

1-33 

4-98 

7 

3-12 

5-37 

10-42 

. . . 

4-25 

1-25 

3-63 

8 

7-83 

2-33 

5-58 

6-12 

3-08 

0-92 

9 

12-34 

2-50 

6-83 

1-00 

2-54 

3-62 

10 

12-12 

4-58 

4-25 

5-71 

2-00 

9-5 

11 

0-33 

5-73 

4-87 

6-42 

2-14 

1-84 

12  Midnight. 

3-29 

6-46 

6-04 

4-79 

0-00 

4-12 

Time. 

May  24. 

May  25. 

May  26. 

May  27. 

May  28. 

May  29. 

May  30. 

Mean. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

h. 

R. 

1 A.M. 

0-25 

0-25 

008 

4-79 

4-70 

1-81 

2 

2-40 

3-37 

0-41 

6-66 

1-08 

0-98 

3 

1-50 

6-41 

6-29 

3-04 

241 

2-73 

4 

5-62 

3-54 

0-95 

6-16 

2-25 

1-50 

5 

6-87 

3-41 

4-16 

2-75 

2-83 

1-77 

6 

4-08 

2-79 

5-79 

7-58 

2-12 

4-47 

7 

2-62 

3-45 

5-58 

12-41 

1-20 

5-05 

8 

1-04 

0-91 

3-83 

8-16 

4-41 

3-67 

9 

zero. 

108 

2-37 

4-33 

6-95 

2-51 

10 

1-29 

2-29 

1-33 

7-50 

11-08 

1-24 

11 

2-70 

4-16 

i-29 

i-33 

13-70 

4-63 

12  Noon. 

3-66 

4-62 

363 

6-83 

10-70 

5-88 

1 P.M. 

1-62 

3-79 

4-37 

4-75 

6-54 

7-70 

4-79 

2 

1-29 

1-68 

3-45 

3-87 

9-0 

13-56 

5-47 

3 

0-62 

0-12 

1-87 

1-62 

2-00 

8-70 

1-82 

4 

0-58 

1-41 

6-45 

6-62 

0-25 

4-58 

0-55 

5 

0-50 

1-28 

4-66 

2-45 

2-37 

6-95 

0-24 

6 

0-37 

0-16 

4-05 

1-22 

3-50 

6-93 

1-35 

7 

0-i2 

0-16 

3 62 

4-95 

4-08 

100 

0-34 

8 

0-04 

6-20 

2-54 

4-50 

4-41 

0-95 

0-21 

9 

0-95 

1-75 

1-66 

5-08 

4-33 

0-20 

1-36 

10 

2-37 

0-29 

1-95 

7-87 

2-75 

0-70 

1-53 

11 

0-54 

0-79 

6-29 

7-91 

2-58 

2-58 

1 05 

12  Midnight. 

0-29 

3-50 

6-08 

1-56 

1-12 

437 

0-26 

72 


MR.  W.  H.  BARLOW  ON  SPONTANEOUS  ELECTRICAL  CURRENTS 


Table  II. 


Mean  deflections  in  each  hour  exhibited  by  a galvanometer  at  Derby,  in  connection 
with  a wire  extending  to  Birmingham,  for  fourteen  days,  commencing  May  17, 1848. 
(The  means  are  taken  from  twelve  observations  in  each  hour.) 


Birmingham  Instrument. 


Time. 

May  17. 

May  18. 

May  19. 

May  20. 

May  21. 

May  22. 

Blay  23. 

Mean. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

1 A.M. 

3-21 

2-00 

15-92 

1-80 

13-24 

4-12 

5-04 

2 

3-75 

5-25 

1-50 

6-02 

6-25 

... 

5-66 

4-74 

3 

11-37 

14-50 

5-66 

0-50 

10-75 

5-16 

2-15 

4 

8-10 

2-50 

6-50 

.3-83 

6-25 

4-30 

0-71 

5 

7-04 

9-25 

710 

8-25 

2-25 

• •• 

2-58 

6 

• •• 

• •• 

4-29 

4-75 

5-60 

1-85 

8-16 

1-19 

7 

0-66 

4-25 

5-83 

6-58 

7-50 

3-53 

8 

10-66 

15-16 

8-60 

3-50 

12-22 

10-03 

9 

9-50 

4-33 

1-25 

8-42 

0-42 

4-78 

10 

3-66 

5-60 

0-92 

6-75 

12-33 

1-32 

11 

4-83 

4-21 

5-83 

11-92 

18-70 

... 

9-10 

12  Noon. 

15-29 

16-37 

11-25 

6-16 

16-21 

13-06 

1 P.M. 

15-79 

6-50 

7-92 

18-88 

10-41 

11-90 

2 

18-92 

11-80 

15-21 

3-66 

8-10 

11-54 

3 

19-42 

... 

7-12 

5-00 

13-54 

5-88 

... 

10-19 

4 

22-60 

22-85 

14-46 

14-75 

12-10 

8-66 

... 

15-80 

5 

19-85 

3-10 

1900 

12-17 

3-50 

12-08 

11-61 

6 

22-21 

18-04 

17-46 

6-61 

... 

10-42 

5-73 

... 

12-31 

7 

2-54 

• •• 

10-12 

15-71 

1112 

17-33 

7-00 

... 

9-79 

8 

13-83 

i-66 

10-33 

8-87 

16-08 

11-62 

5-23 

9 

20-08 

2-65 

0-01 

12-83 

0-25 

9-42 

4-31 

10 

13-71 

4-71 

4-75 

7-60 

10-16 

7-83 

• •• 

0-30 

11 

1-83 

7-00 

6-'50 

12-83 

204 

7-42 

1-02 

12  Midnight. 

2-16 

4-10 

24-42 

10-30 

10-83 

304 

9-14 

Time. 

l\Iay  24. 

May  25. 

May  26. 

May  27. 

May  28. 

May  29. 

May  30. 

Mean. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

L. 

R. 

1 A.M. 

0-20 

0-54 

0-83 

3-58 

3-87 

1-50 

2 

1-79 

3-04 

0-75 

6-20 

0-83 

0-69 

3 

0-75 

6-08 

zero. 

1-50 

1-16 

1-43 

4 

4-12 

0-75 

0-50 

6-70 

1-00 

0-73 

5 

4-29 

1-62 

1-79 

3-50 

2-04 

0-43 

6 

1-70 

0-79 

2-79 

6-29 

4-91 

3-29 

7 

0-62 

... 

1-54 

3-04 

10-79 

6-91 

... 

4-58 

8 

0-12 

6-04 

1-79 

5-91 

8-66 

• •• 

3-28 

9 

zero. 

1-04 

0-75 

3-58 

8-25 

2-30 

10 

• •• 

1-20 

2 16 

0-37 

6-64 

5-37 

0-34 

11 

2-46 

4-37 

0-79 

1-54 

6-87 

3-20 

12  Noon. 

• •• 

3-79 

5-08 

4-18 

5-83 

4-50 

4-67 

1 

4-66 

4-33 

5-62 

5-33 

6-04 

2-41 

4-73 

2 

3-71 

2-16 

5-33 

4-62 

10-00 

6-00 

... 

5-30 

3 

0-87 

1-02 

4-58 

2-41 

3-35 

3-95 

2-69 

4 

0-37 

0-25 

2-54 

1-25 

2-45 

1-25 

1-35 

5 

0-10 

0-28 

2-33 

0-25 

4-83 

3-54 

1-11 

6 

1-04 

2-00 

2-25 

3-86 

7-35 

2-50 

2-41 

7 

1-04 

1-62 

0-29 

8-29 

i-66 

2-66 

1-06 

8 

0-83 

1-37 

0-29 

7-16 

1-08 

2-25 

0-95 

9 

1-71 

2-70 

6-08 

2-83 

1-70 

2-62 

... 

0-44 

10 

3-00 

0-75 

6-’37 

6-04 

6-’33 

1-83 

0-69 

11 

0-70 

1-29 

i-37 

7-87 

1-91 

1-33 

... 

1-29 

12  Midnight 

... 

0-45 

3-’20 

2-91 

0-62 

1-25 

0-20 

0-32 

[ 73  ] 


VII.  On  the  Meteorology  of  the  Lake  District  of  Cumberland  and  Westmoreland  ; 
including  the  results  of  Experiments  on  the  fall  of  Rain  at  various  heights  above 
the  Earth's  surface,  up  to  ^i&Qfeet  above  the  mean  sea  level. 

By  John  Fletcher  Miller,  Esq. 

Communicated  by  Lieut.-Col.  Sabine,  For.  Sec.  R S. 

Received  April  4, — Read  May  18,  1848. 


Introduction. 

Nearly  four  years  have  now  been  devoted  to  the  investigation  of  the  fall  of  rain 
in  the  lake  districts  of  Cumberland  and  Westmoreland  ; and  two  complete  years 
have  elapsed  since  the  experiments  were  commenced,  with  a view  to  ascertain  the 
amount  of  rain  deposited  at  great  elevations  above  the  sea,  extending  to  the  tops  of 
our  highest  English  mountains. 

As  the  investigations  proceeded,  some  remarkable  results  were  elicited,  which 
coming  to  the  knowledge  of  the  Royal  Society  early  in  last  year  (1847),  the  Council 
kindly  expressed  a wish  to  contribute,  from  the  Donation  Fund,  the  sum  of  twenty 
pounds  towards  the  current  expenses  attending  the  inquiry.  The  donation  was 
accompanied  by  a request,  that  as  early  as  convenient  after  the  close  of  the  then 
current  year,  I would  transmit  to  the  Royal  Society  a resumd  of  all  that  I had  done 
in  this  department  of  meteorology. 

This,  resume  I have  endeavoured  to  communicate  to  the  Society  in  the  annexed 
paper. 


Whitehaven,  March  1848. 


J.  F.  Miller. 


MDCCCXLIX. 


L 


74 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


Table  I. 

Fall  of  Rain  in  the  Lake  District  of  Cumberland,  &c.,  for  Six  Months,  commencing 
the  1st  day  of  July,  and  ending  the  31st  day  of  December  1844. 


1844. 

Whitehaven.  | 

Keswick. 

Ennerdale 

Lake,  Bow- 

ness. 

Stonywath,  j 

two  miles  j 

west  of  the  1 

lake.  1 

Loweswater 

Lake. 

South  end 

of  Crninmock 

Lake. 

Gatesgartli. 

Westmoreland. 

Wastdale 

Head. 

Troutbeck 

near 

Kendal. 

Grasmere. 

July 

4-183 

3-052 

5-549 

4-151 

3-425 

4-59 

5-70 

4-178 

4-874 

6-36 

August  

1-999 

5-737 

4-863 

4-164 

5-564 

7-55 

9 08 

4-623 

6-856 

10-74 

September  ... 

5-809 

4-780 

6-327 

5-417 

6-185 

6-33 

7-93 

5-734 

5-381 

9-33 

October  

4-335 

5-273 

6-240 

4-493 

7-131 

8-22 

10-78 

6-142 

8-644 

9-45 

November  ... 

1-936 

2-842 

3-700 

2-151 

3-048 

3-69 

5-49 

3-987 

6-397 

5-26 

December  ... 

•309 

•108 

•790 

•170 

•307 

•33 

•47 

1-022 

845 

-47 

Total  

18-561 

21-781 

27-469 

20-546 

25-650 

30-71 

39-44 

25-676 

32-997 

41-51 

Wet  days 

79 

84 

75 

83 

93 

82 

77 

71 

Table  III. 

Wet  days  in  1845. 


1845. 

Whitehaven. 

The  Flosh. 

Cocker- 

mouth. 

Keswick. 

Loweswater. 

Crummock 

Lake. 

Gatesgartli. 

<y 

'M'6 

^ a 

t/i  0 

C3  'T* 

Grasmere. 

Langdale. 

Troutbeck. 

Seathwaitc. 

January  

21 

16 

19 

21 

21 

21 

21 

20 

22 

18 

22 

February 

10 

5 

6 

9 

8 

8 

11 

9 

9 

4 

11 

March 

14 

11 

14 

14 

14 

12 

15 

13 

15 

12 

15 

April  

13 

10 

11 

12 

12 

11 

12 

12 

12 

12 

11 

May  

14 

14 

16 

15 

15 

17 

16 

14 

12 

12 

15 

June  

16 

15 

18 

17 

15 

16 

17 

16 

16 

18 

17 

18 

July 

13 

15 

17 

11 

15 

15 

16 

16 

16 

15 

17 

15 

August  

17 

20 

21 

20 

18 

21 

19 

21 

15 

20 

16 

22 

September  ... 

15 

12 

17 

13 

13 

16 

16 

17 

14 

17 

14 

15 

October  

20 

20 

26 

21 

19 

23 

23 

26 

21 

22 

19 

21 

November  ... 

17 

15 

21 

19 

20 

18 

19 

21 

19 

19 

17 

20 

December  ... 

23 

22 

26 

23 

25 

24 

25 

26 

25 

26 

22 

26 

Days  

193 

175 

212 

195 

195 

202 

210 

211 

196 

137 

180 

211 

Table  II. 

Synopsis  of  the  Fall  of  Rain  in  the  Lake  Districts,  &c.  of  Cumberland  and  VVestmoreland,  in  the  year  1845. 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


i; 

cS 

, 

c3 

CS 

> 

H H 

> 

2 

> 

5/3 

Z JO 

w 

CO 

z 

• 

z 

> 

c/i 

z 

c/2 

z 

w 

Ed 

02 

• D 

ni 

Z 

a 

^ w °d 

^ =• 

> 

(/} 

. 2 

w 

c/2  ^ 

is 

z 

c/3 

z 

i 

z 

% 

c/l 

z 

00 

r-s  J>.  »D  ID 

TP 

x>. 

00 

©^  ID 

iD 

©^  CD  CD 

t'-. 

GO 

CO 

X 

C tr> 

CO 

CO  o 

00  00 

ID 

CO  ^ 

O 

r-l 

l-H  1— ( 

r-^ 

l-H 

©< 

©^ 

ID 

I—*. 

ID 

LD 

TjH 

©^ 

©1 

^ CD 

o 

ID 

Tp 

00 

o 

tD 

D 

x>.  i>.  CO 

00 

CO 

X 

4* 

©^ 

p 

r>H 

1— ( 

©^ 

CO  c*-, 

' 

CO 

©)  CD  CO 

CO  O 

QO 

ID 

©) 

tP 

X 

©f 

LO 

»D  CO 

00 

^ CO 

00 

CO 

GO 

CO 

o 

o 

©< 

©t  ^ 

©^ 

o ^ 

1—' 

ID 

!>.  J>.CD 

o 

lO 

©^ 

O CO 

©^ 

ID  CD 

O CD 

•—4 

CO 

r-l 

.S 

1—1 

r— 1 

p-H 

©) 

©1 

©i 

CD 

^ LD 

lO  CD  CD 

o 

ID 

ID 

»D 

CO 

CO 

O CO 

o 

O CD 

CO 

ID 

CO 

Tp 

ID 

O 

o 

C*3  o ID 

©< 

©i  CO 

CO 

<— * 

ID 

ID 

CO 

t>.  ID 

©^ 

ID  ^ 

ID 

TfH 

GO 

X 

iD 

cb 

f-H 

t>* 

o 

o 

O 

CO 

»D  ©) 

r-K 

CO 

ID 

r-H 

X 

ID 

o 

CO 

t-H 

00 

ID 

CO 

CO 

ID 

CO 

O i>.  ^ CD  »D 

©^ 

!>.  ©^ 

©i  CD 

X 

O 

1— 1 

cc 

l>»  o 

o 

©)  ©t 

ID 

CO  00 

X 

CO 

CO 

O CO 

CO 

00 

Tp 

X 

»— 1 

CO 

©1 

CO  o 

00  00 

>D 

00 

o 

CO 

!>. 

4 

©^ 

•-H 

CO 

O CD  ^ 

©^ 

!>•  CO  !>. 

o 

o 

C2 

X 

!>.  O CO  CD 

CO  CO 

1— 1 

ID 

©< 

ID 

Tp 

Tp 

cn 

r-i 

J>.  CO 

ID  CD 

1—1 

GD 

00 

X 

i>* 

rH 

X 

o 

CO  OS 

QO  CD  CD  CD 

CO 

©i 

o 

CO 

^ ID 

©) 

»D 

ID 

Tp 

CD 

CD 

Tp 

<—1 

00 

00  00  CO 

CO  ©i 

00 

ID 

Tp 

CO 

i—t 

c- 

LD  ^ 

©^ 

lb 

00 

CD 

CO 

CO 

tD 

o 

o 

»D  O 

o 

o o 

ID 

O 

ID 

o 

ID 

o 

to  to 

•-1  O 

o 

ID  ID 

O 

CO 

tP 

Tp 

X 

•—1 

ID 

©^ 

iD  w> 

o 

TjH 

pH 

X 

C to 

CO 

ID  LO 

o 

ID 

GO  to 

o 

cb 

l—t 

<— 1 

!>• 

to 

00  CO 

o 

G<  ei  <3 

TP 

00 

O CD 

©? 

©< 

o 

00 

CO  ^ 

o 

o 

Tp 

TP 

CO 

O 

o 

CO  00 

©^ 

o ^ 

00 

o 

CO 

■-H 

ID 

©^ 

c 

cb 

©t 

GO 

ID 

»D 

!>.  X 

©^ 

tD 

ID 

LO  O 

o 

o o 

o 

ID 

ID 

ID 

o 

O 

C3  ^ 

CO  CO 

CO  o 

©i 

©i 

CO  CO 

CO 

1— ' 

o 

00  CO 

CO  O CD 

00 

ID 

O 

ID 

CO 

CO 

,—1 

CO  ©i 

1 

CO  ©^ 

00 

CO  CD 

CO  CD 

cb 

.F-C 

Tp 

00  tr> 

CD  ©^ 

©1 

ID 

O 

ID 

o 

00 

!>.  ©t  CD 

t>.  00  ID 

©^ 

■—I 

CO 

tP 

©^ 

o 

c 

©^ 

rJH  ©^ 

CO  CO 

!>.  Tp  CD 

ID 

C>*  ‘O 

o o 

©^  o 

o 

»D 

CO 

O 

©> 

CO 

CO 

ID  CO  i>*  00 

o 

O 

ID 

ID 

©< 

X 

o 

00  !>.  CO 

CO 

<— 1 

tP 

GO 

CO 

©^ 

TP 

c 

©^ 

©^  l—l 

CO  rH 

ID 

©i 

©1 

CO 

cb 

CO 

o 

ID  O 

CO  o 

ID 

CO 

ftj 

j>. 

CO 

CO  GO 

00 

CTi  O 

CO  ID 

tP 

©1 

©■? 

o 

lO 

00 

t>*  ID 

O CO  CO  CD 

!>•  O CD 

©^ 

s 

©i 

CO  ©i 

r-i 

Tfi  ©i  tD 

CO  CD 

tP 

ID 

CO 

& S 

— S-I 

“XS  O 

rt  20 


•p'B9H 


•aqB'q  qoorainruQ 


•9J[BT  9|Bpj9Uua; 


•qotMS9;^ 


•q:jnoaia9qD03 


•n9ABq9jTq^Y 

JO  qjnos  S911IU 
rZ  ‘qsoii  9qx 


00  (1)  _ 


O 


li  ^ s 

i "S  3 "s  2 o " 


L 2 


The  ^re«^er  portion  of  the  Tables  for  1845,  and  the  last  six  months  of  1844,  have  appeared  in  the  Edinburgh  Philosophical 

Journal,  but  are  added  here  for  the  sake  of  completeness. 


Synopsis  of  the  Fall  of  Rain  in  the  Lake  Districts  of  Cumberland  and  Westmoreland  in  the  year  1846. 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


At 

Seathwaite, 

one  daily 

observation. 

CA 

& 

s.n. 

7 

i 

i 

CO 

a 

75 

w,  var. 

S.E.  & N.W. 

X 

N.  & N.W. 

X 

ns 

•S 

be 

c 

'<3 

u 

;At  Crummock 

Lake,  t^vo 

1 daily  observa- 

tions. 

CO 

C 

<si 

CO 

& 

Cft 

08 

i 

75 

ts 

75 

s,  to  w. 

5 

>■ 

lA 

N.E. 

75 

fk 

At  the  coast, 

two  daily 

observations. 

V 

CO 

Cfj 

d 

C: 

7 

> 

75 

75 

'Z 

> 

m 

CO 

X 

X 

A 

z 

X 

i 

At 

18  inch. 

above 

the 

surface. 

.s 

CO 

cp 

n 

10-87 

4-78 

fM 

n 

cb 

10895 

cb 

05 

X 

"rt 

cn 

' At 

6 inches 
above 
the 

surface. 

in. 

1707 

11-51 

17-85 

0 

4-40 

0 

X 

0 

n 

X 

if5 

0 

0 

25-43 

CO 

0 

cb 

143  51 

From 

June 

84-98 

Lang- 
dale 
Head, 
250  ? 
feet 
above 
the  sea. 

in. 

15-63 

1225 

16-02 

6-24 

4-13 

CO 

GC 

kh 

n 

CO 

cb 

8-45 

21-25 

10-31 

cb 

0 

n 

c 

cS 

o 

s 

Grasmere, 
180  feet 
above 
the  sea. 

in.  i 

17013 

10-917 

15-964 

896-9 

a 

ir: 

0 

1^1 

cc 

C5 

13  909 

6-685 

3-310 

16-320 

7-045 

CO 

n 

110-329 

The 
How,  : 
Trout- 
, beck. 

XI 

5-786 

9-774 

4-790 

3-134 

3-742 

10-040 

5-552 

Oi 

10 

cb 

12-014 

C5 

CO 

Ip 

n 

CO 

0 

cb 

77-719 

Wast- 
dale 
Head, 
166  feet 
above 
the  sea. 

in. 

12-97 

6-60 

10-35 

6-59 

1 

3-65 

5 33 

16-82 

CO 

X 

3-79 

lb 

8-59 

CO 

Ip 

CO 

C5 

lb 

0 

From 

April 

76-01 

Eskdale 

Foot, 

1 height 

: unknown. 

C 

4-38 

3-15 

3 91 

n 

n 

X 

CO 

X 

cb 

n 

CO 

0 

?o 

CO 

is 

n 

05 

cb 

52-11 

From 

April 

Gates- 
garth, 
326? 
feet 
above 
the  sea. 

in. 

12*81 

88-6 

15-07 

7-11 

C5 

zz 

X 

dn 

89-01 

CO 

CO 

cb 

18-78j 

10-15 

0 

lb 

121-90 

Crum-  ' 

mock  ; 

Lake,  i 

283  feet 
above 
the  sea. 

in. 

; 8*98 

1 

is 

in 

0 

CO 

n 

lb 

n 

C5 

is 

cb 

16-22 

870 

1 

3-90 

cb 

05 

Lowes- 
water 
I^ake, 
336  feet 
above 
the  sea. 

i 

»> 

nr: 

X 

4-395 

2-505 

5-010 

13-430 

5-420 

i-O 

0 

C5 

n 

13-490 

»o 

4-095 

79-249 

ns 

u 

Vale  of 
Giller- 
thwaite, 
286  feet 
above 
the  sea. 

c 

X 

CO 

15-20 

9-01 

lO 

n 

15-78 

7-90 

3-94 

63-82 

From 

May 

a 

Bow- 
ness, 
246  feet 
above 
the  sea. 

QC 

c 

.5* 

X 0 

X 

5-190 

3-130 

5-020 

0 

X 

cb 

7-320 

3-250 

14-240 

7-100 

4-100 

83-970 

C 

0 « 

^ 0 

Kes- 
wick, 
250  feet 
above 
the  sea. 

QC 

8-542 

4-546 

1-724 

4710 

9-320 

CO 

n 

0 

n 

12-248 

n 

*>. 

cb 

2-586 

67-678 

Cocker- 

mouth. 

1 

in. 

4150 

2-445 

5-115 

2-630 

1-680 

3-840 

10  190 

4-650 

2-100 

8-940 

4-080 

2-590 

52-410 

The 

Flosh, 

: 3 miles 

south  of 
White- 
haven. 

in. 

5*44 

2- 17 

4-80 

3- 60 

2-64 

2-38 

X 

X 

X 

5-31 

2-86 

9-54 

4-90 

CO 

n 

55-16 

Saint 
James’s 
Church 
Steeple, 
78  feet 
above 
the 
street. 

in.  ' 

1 3*290 

1 i 

•960 

2-150 

2-130 

1-623 

1-680 

6-995 

3-320 

2-157 

6-115 

3-760 

1-242 

35-422 

OJ 

s 

1 

Round 
Close, 
480  feet  1 
above  ! 
the  sea. 

i 

0 

CN 

2-437 

2-103 

8-626 

10 

0 

cb 

2-574 

n 

0 

X 

X 

10 

1-889 

36-195 

From 

April 

High 
Street, 
90  feet 
above 
the  sea. 

1 in. 

4*604 

2-007 

4-460 

2-848 

2-317 

2-311 

190-6 

4*066 

1 

uO 

X 

n 

7-982 

4-671 

0 

10 

49-134 

From 

April 

38-063 

1846. 

January  ... 

February . . . 

MaroL  i 

7^ 

< 

> 

^ J: 

June  

July 

August  ... 

1 

September 

1 October... 

November 

December 

Inches 

DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


77 


Table  V. 

Wet  days  in  1846. 


1846. 

1 Whitehaven. 

Tlie  Flesh. 

Cocker- 

mouth. 

Keswick. 

Loweswater. 

Crummock 

Lake. 

<V 

2 « 

00  <V 

Eskdale. 

Grasmere. 

Troutbeck. 

Langdale 

Head. 

Seathwaite. 

January  

22 

25 

26 

21 

20 

21 

28 

26 

23 

28 

25 

February 

15 

14 

16 

13 

13 

15 

18 

15 

16 

16 

15 

March 

18 

19 

23 

23 

18 

21 

25 

21 

20 

21 

23 

April  

17 

21 

24 

22 

16 

22 

23 

19 

21 

20 

22 

21 

May  

12 

13 

15 

13 

14 

12 

14 

15 

12 

13 

13 

14 

June  

9 

10 

12 

10 

11 

11 

11 

9 

9 

9 

9 

11 

July  

24 

24 

28 

27 

22 

23 

27 

27 

21 

22 

23 

25 

August  

13 

13 

18 

17 

18 

18 

22 

19 

14 

17 

15 

16 

September  ... 

12 

13 

13 

11 

11 

14 

11 

11 

10 

9 

11 

12 

October  

23 

23 

23 

24 

24 

25 

23 

23 

23 

20 

23 

04 

November  ... 

18 

17 

19 

18 

17 

17 

17 

17 

16 

18 

16 

17 

December  ... 

17 

16 

17 

14 

14 

17 

15 

15 

14 

7 

16 

16 

Davs  

' 

200 

208 

234 

213 

198 

216 

234 

155 

202 

194 

213 

219  1 

Table  VI. 

Temperature  at  Seathwaite,  taken  by  Self- registering  Thermometers  made  by 

Watkins  and  Hill. 


On  Grass. 

1846. 

Maximum. 

Minimum. 

Mean. 

Mean  at 

9 A.M. 

Radiation. 

Maximum. 

Mean. 

March 

0 

48 

0 

21 

38-84 

3^39 

0 

18 

0 

April  

60 

30 

43-68 

42-78 

12 

4-61 

May  

65 

41-5 

52-47 

52-54 

18 

8-71 

June  

84 

44 

64-83 

63-87 

23 

11-80 

July  

79 

50-5 

59-41 

58-22 

12-5 

August  

78 

47 

62-03 

60-58 

20 

September  ... 

76 

40 

58-20 

56-16 

21 

12-00 

October  

61 

30 

47-91 

47-50 

17-5 

November  ... 

54 

26 

43-68 

43-21 

December  ... 

47 

14-5 

32-13 

32-05 

84 

14-5 

50-318 

49-43 

At  Whitehaven  ... 

52-295 

Difference  

1-977 

Table  Vll. 

Synopsis  of  the  Fall  of  Rain  in  tlie  Lake  Districts  of  Cuiiibei  land  and  Westmoreland  in  the  year  1847. 


78 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


•9jreAiinB3s  spam  SnjttBAajj 

^ 

s.w. 

XX. 

Borrowdale. 

■^9IFA 

^Cp^CO'^Cr>O^COL>.OOGOC^ 

G^ 

ci 

o 

XIX. 

Seathvvaite. 

■panojS  9qi  9AoqB 
saqoui  81  ‘ppid  iq 

ocoiooo-^coi>*^ocr^coci) 

£c5cx)(J)ci<i)i>»cooGiO'^o 

^ r-  Gt  ©i 

o 

O) 

o 

G^ 

XVIII. 

■puno.iS  9qj  9AoqE 
S9q9Ul  9 *U9piE0  uj 

01>*CO^Xr>.©^OOQOG^O'^ 

0^©^ipOOOO^C©^G>iCCX)0 

= cb(X)©^cS(XJ>*Aocoo^o 

^ rl  ©^  ©^  ©^ 

^ 

©^  lO  00 

CO 

©>  '«^'  u© 

1 XVII. 

Westraorelaiul. 

•B3S  aqi  3AoqB 

I83J  <Oes  ‘PB8H  nispSuBT 

k0ocr>iiscoi>.i>.*^coi>.-^co 

lO  o o 

C5  O 

G^  i>*cb 
-H  ©i  CO 

i 

•lAX 

*E9S  9qx 

OAOqE  X99J081  ‘9i9taSEJf) 

i>,cr)^ioc^oocoioooG^ooo 

»-©COC^COOL^^^I>»0^iOO 

CO  C5  00 

CG  ©i  O 

CO  CO  o 

CO  o ^ 

CO  G^ 

XV. 

•5l09q}iio.ix  ‘Atopi  ai[x 

lOC^O’^^GOCiC^COO^’^t^ 

05  ^ O 

O ^ O 00 

O CO  oo 

(X)  ^ci  ^ 

X^  !>,  IC 

1 XIV. 

■E9S  9q^ 

9A0qE  :^99J  991  ‘pE9H  9Fp|SE^V 

CiO.-^l>*O©)OC3’^C0’^‘^ 

CO  lO 

CO  ;0.  lO 
ci  cS  (Jd 

05  o O 

XIII. 

Eskdale. 

Head. 

'!t<tDGOG'(coic.-He<'>*it^ioeo 

.C»CH>.CO'^OG?aO'— 

.gwcoAi-ihiodjcodjaDocGao 

CO  \ \ 

^ : : 

: I 

^ : : 

XII. 

Foot. 

t£'C^cricnc2coi>.c<5aooa5'^ 

.cr>GO.-<-.^a2(Ncowcpcoioo 

.Swc^i-'OtcG-ifi-ids'iQbooo 

58-66 

*E9S  9q; 

9A0qE  a99J  93g  ‘qTIESs9:fE0 

*^i>.iOi>*o^coo*5'^coc©c.oc^ 

^COOCO’^C©GOC3^'^'»^»p 

G’^ib©^i»OiOi^oocS©^ci 

^ ^ ^ 

106-25 

121-90 

124-13 

x' 

*E9S  aq:^  9AoqE  ^99j  ggS 

‘9qEq  qDouiainaQ  jo  :jooj; 

u^oa^ic^oo»oi>«c3  0— 'CO 

.5co^©^'^'^>iA(X>*cSA)t^©) 

GX  !>.  00 

^ T*  T 

G^  ci  x>* 

GO  05  00 

•E9S  9q:^  9A0qE 
:^99j  9gg  ‘9qET;  J9^EMS9Ai.oq 

LOOCjDt>*OiOO©)'^»0>^l>* 

COOLOGOOO^^i^C3CO©^»0 

O 05  Gi 

05 

(^  Gi  ip 
ci  05 

c^  J>.<CD 

VIII. 

•E9S  9qi  9A0qE  ^99J  qg^  ‘9JEp 

-J9un3  ‘oqBAYqusiIlO  JO  dye^ 

o^Tj'o©)fOco©^^oocri 

CO  !>.  00  ©1 
^ 00  OO  GO 

o CO  ci 

00  00  t>*  iO 

VII. 

•E9S  9q^  9A0qE  :j99J  ggg  *qOLtt.S9]^ 

^oo©^c©ocr)'^oco'X^c» 

CO)  00  G^  05 

00  o G) 

CO  'Cp 

i)  X^.  Gi  o 
no  GO  GO 

> 

*E9S  9q^  9A0qE  ;99J  Q X ^ ‘ AVEppp[S 
JO  9SEq  ‘spEjx  9jiEAiqxn9ssEg 

^COOCiDi^cS^COCOOCOOC^ 
,coi>.^oc*5iO'-Hr-*'^i— •X'-ic 
^go^J-,fl»©^c©:©rl4W'^iS<X)cS 

44-45 

> 

•qXtiomjgqooQ 

o^©^:0'rt^oGiJ>*cr>i>.L^OQO 

* r^COCO^’^4'i^5C)Oci 

no  CO 

iO  05 

G)  ©>  GO 

Ttn  lO  ^ 

> 

•U9AEq9iiq^Y  JO 
qxnos  sopni  99xqj  ‘qsojg  9qx 

05— iCGL-^'^OOOr-iCOOr^ 
^oo«s^G'^oto©Jcr3©^iot'^a5 

O GO  O ^ 

a>  ^ o cp 

x^  io  CO 
lO  lO  CO 

5 

Whitehaven. 

•:^^9J;s  9qi 

9AoqB  :>99j  8^  ‘9id99:js 
q9anq3  s.sainBp  •;§* 

L©OCCI>*»-f5'CO^'^l'^OC©’Tf< 

coi>*c*5i'-*coo©^'^0'^C5Cr5 

focooooa^rfoooocoaococ^ 

£4H4-i4-i-^(k^*  o^ck(^:>ic^ 

CO  ©i  05  G^ 

^ ©^  00  GO 

X^  Tf  Cp 

o ib  CO  x^ 

CO  CO  CO  G) 

- 

•B9S  9qj  9A0qE 

08^  ‘9S0X3  punog 

G0'CO^a5l>-i>.‘O'^G0  0^^'-^ 
©^OCr5000^t-^C5^4>*OCO^ 
lO  •^  <— 1 W lO  ©'t  !>.  — 1 ©i  ©^ 

^d4-i4^rl^©<c©0  * ^cGic»ci> 

CO  • • 

^ : : 

o • • 

^ ; i 

- 

*E9S  9qa 

9A0qE  599J  06  ‘|39-I|S 

c©i>.o  o CO  ©ico<co 

t>*©)L^C^G^^J>*O^COOCOC5 

Q0Q0CCi©'*!J^CC»t^'^l>*^C5n© 

' 4^CGiO 

F-N  ^ x^  CO 

GX  CO  O ©^ 

05  ^ G^  X^ 

05  05  GO 

TJH  CO 

No. 

00 

Jan. 

Feb. 

Mar. 

April 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 

X>.GD  iO 
•rf  •'f 

OO  GO  GO  00 

^ ^ rH 

o -t: 


s 

o 


is 


O 


CD 

CO 
00  -t 

r-H  00 


o 


bn 

>.  S 
S OJ 


0)  D 
fcD  O 
=3  ^ 
cS  :5 
bO  . 

03  f/5 


IS 

o 

a 

4-> 

to 


bJD 

C 


2 W ^ 

s; 

0)  C3 

e — <3^ 

.s  ^ ^ 

I— ' <D 

? -2  "c 
.a  'ts  " 

c-  t/5  v-" 

•s  ^ 

" S' 

bX)  OS 

.!2  fan  ° 

^ a;  -S 

^ ^ 

S3  ^ 

!>»  C t3 


a>  s-i 

.3  W 

fl  ^ 

^ *5 

M oo 


a 

ctf 


73 


Cl. 

ct 

s 

fcX3 

.5 

c 

a 

S 

o 


.S5 

£ 

3 

C 

bD 

.5 

c 

o 


a> 

4S  cd 
bX)  o> 

IS 

CD  ^ 

4S  ^ 


4-> 

g 

'S 

CD 

C 

O 

•4^ 

O 

'i 


s ^ 

g S 

CS 

G w 
O CD 

Pi 


O)  ^ 
-=  § 
H S 
(/? 

* (D 
•St  bD 

* S 

b£) 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


79 


Table  VIII. 
Wet  Days. 


1847. 

Wliitehaven. 

The  Flosh. 

Cockermouth. 

Keswick. 

Loweswater. 

Butterraere. 

WastJale.  | 

Grasmere. 

Langflale. 

Troutbeck. 

Bassenthwaite. 

Seathw^aite. 

Stonethwaite. 

January  ... 

13 

15 

15 

14 

13 

14 

14 

15 

15 

10 

11 

13 

14 

February... 

15 

14 

13 

10 

10 

12 

16 

12 

12 

12 

12 

10 

10 

March 

12 

13 

17 

14 

13 

15 

20 

15 

12 

12 

19 

14 

14 

April  

17 

18 

20 

17 

17 

14 

20 

17 

17 

17 

18 

16 

16 

May  

20 

16 

20 

22 

20 

22 

23 

23 

21 

18 

20 

23 

21 

June  

14 

14 

17 

17 

15 

17 

16 

18 

20 

18 

20 

15 

15 

July 

8 

8 

11 

10 

9 

9 

16 

10 

12 

9 

10 

13 

11 

August  ... 

18 

17 

21 

18 

18 

18 

20 

15 

18 

16 

16 

17 

15 

September . 

20 

17 

22 

24 

21 

21 

24 

22 

23 

21 

21 

23 

23 

October  ... 

14 

15 

16 

18 

17 

17 

17 

19 

17 

18 

14 

19 

17 

November^. 

22 

20 

20 

22 

21 

22 

23 

20 

24 

21 

20 

21 

21 

December.. 

18 

16 

18 

18 

16 

18 

24 

18 

18 

16 

18 

18 

18 

1847 

191 

183 

210 

204 

190 

199 

226 

204 

209 

188 

199 

202 

195 

1846 

200 

208 

234 

213 

198 

216 

234 

202 

213 

194 

219 

1845 

193 

175 

212 

195 

195 

202 

211 

196 

180 

211 

1 

80 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


l-H 

n 


> 


CO 


-O 


> 

o 

;zi 


o 

Tfl 

oo 


p 

5 


f/? 

QJ 

00 

5 

o 


o 


(K 

a 


OJ 


.s 

(l> 

c5 

4-» 

0) 

c 

<4>^ 

05 

rt 

o 

.§ 

e 

a> 

CO 

<u 

•4^ 

C 

•4^ 

o 

4.» 

1) 

CO 

0) 

43 

4-> 

bx) 

;3 

o 

o 

40 

•4^ 

CO 

4-3 

c3 

■ ^ 

(L^ 

E 

CO 

4^ 

o; 

*5 

o 

"IS 

■tj 

a> 

»v< 

CO 

n3 

o 

C 

4-> 

ci 

(D 

40 

4^ 

"t- 

bS) 

o 

C 

c 

’C 

<p 

04 

•4^ 

S 

CO 

CL» 

O 

o 

o 

.s 

a> 

iO 

13 

o 

nr 

*CO 

•4-i) 

CO 

.a 

d 

o 

o 

6 

bo 

*o 

> 

c 

d 

o 

4.3 

<u 

Sh 

a> 

CS 

no 

*C5 

Ih 

o 

CO 

w 

.s 

0) 

n3 

40 

•4^ 

d 

o 

fcX) 

c 

d 

o 

% 

nr 

o 

d 

a; 

n:3 

0) 

a; 

40 

4^ 

?5 

’co 

*4^ 

a 

o 

nr 

u 

<D 

4-3 

CO 

o 

CD 

4^ 

u 

05 

a> 

443 

O 

CO 

d 

(U 

CO 

d 

> 

CO 

o 

CO 

d 

pL, 

<D 

CO 

0) 

d 

<D 

ffi 

<D 

(1) 

4~> 

a; 

m 

0) 

40 

> 

o 

40 

CO 

d 

<u 

0) 

fc£> 

d 

d 

bD 

o 

a> 

40 

03 

H 

* 

-H 

quantity  up  to  the  time  the  other  instruments  were  fixed. 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


81 


The  following'  Table  exhibits  the  particulars  of  rain  obtained  from  the  Mountain 
Gauges,  between  November  1846  and  April  1847  (inclusive),  during  which  period  the 
water  in  the  receivers  was  more  or  less  frozen.  The  total  quantities  only  are  inserted 
in  the  preceding  Table. 

Table  X. 


1846. 

Sea  FeU. 

Great 

SparkUug 

Stye 

500  feet. 

Valley. 

Seatollar 

Valley. 

Gable. 

Tarn. 

Head. 

Wastdale. 

Common. 

Seathwaite. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

Nov.  30. 
Dec.  31. 
1847. 

Solid. 

1-80 

Solid. 

3-90 

9-40 

6-50 

7*32 

7*13 

I 13*90t  1 

8*59 

6*53 

j 13*63  1 

10*46 

6*70 

Jan.  31. 

Solid. 

Solid. 

Solid. 

Solid. 

2*00 

3*99 

Solid. 

6*29 

Feb.  15. 

Solid. 

Solid. 

2-70 

4*80 

6*40  to  28th. 

Solid. 

8*27  to  28th. 

March  8. 

Solid. 

Solid. 

0-58 

5*47 

6*56 

7*71 

March  22.* 
April  10. 

13*33 

Solid. 

11*08 

Solid. 

6*68 

3*41 

0*86 

4*10 

5*05 

1*91  to  31st. 

1*02  to  31st. 

2*53 

April  30. 

3*14 

3-15 

2*55 

2*84 

2*71 

5*37 

5*15 

6*81 

In  six  months 

18-27 

18*13 

31*82 

32*52 

30*22 

32*79 

27*51 

41*06 

Table  Xl. — Showing  the  proportion  which  obtains  between  the  quantity  of  rain  de- 
posited on  the  Mountains  and  in  the  Valley  in  the  Summer  months. 


1846. 

Sea  FeU, 
3166  feet. 

Great  Gable, 
2925  feet. 

Sparkling 

Tarn, 

1900  feet. 

St3'e  Head, 
1290  feet. 

The  Valley. 

Borrowdale. 

Seatollar 
Common, 
1334  feet. 

Valley. 

Wastdale. 

Seatbwaite. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

May  

2*40 

3*13 

4*11 

3*80 

3*65 

2*75 

4*40 

June  

5*00 

7*60 

6*55 

6*26 

5*33 

5*70 

6*42 

July  

14*38 

16*87 

22*73 

17*76 

16*82 

18*35 

20*80 

August  

7*05 

8*65 

12*03 

11*03 

8*96 

8*15 

10*58 

September 

3*22 

3*32 

5*06 

4*22 

3*79 

3*75 

4*60 

October  

13*40 

12*82 

20*35 

15*35 

15*75 

17*42 

25*43 

1847. 

May  

6*16 

5*56 

7*59 

7*56 

5*30 

7*13 

8*08 

June  

5*05 

6*57 

8*13 

7*12 

6*62 

5*71 

7*27 

July  

3*25 

3*10 

4*15 

3*66 

3*80 

2*50 

3*32 

August  

8*39 

7*90 

12*00 

10*22 

7*79 

10*38 

10*48 

September 

8*75 

9*22 

12*43 

10*92 

11*94 

12*06 

13*28 

October 

12-38 

10*95 

18*00 

17*50 

13*53 

19*02 

20*52 

In  twelve  months.. 

89*43 

95*69 

133*13 

115*40 

103*28 

112*92 

135*18 

Table  XII. — Showing  the  proportion  in  the  Winter  months. 


1846. 

Sea  Fell. 

Great  Gable. 

Sparkling 

Tarn. 

Stye  Head. 

The  Valley. 

Borrowdale. 

Seatollar 

Common. 

VaUey. 

March  

in. 

in. 

in. 

in. 

in. 

in. 

in. 

6*51 

7*47 

4*83 

14*94 

5*38 

10*35 

6*59 

14-20 

7*53 

17*85 

7*70 

April  

November  I 

4*39 

17*82 

to  1847.  )> 

April  J 

18-27 

18*13 

31*82 

32-52 

32*79 

27*51 

41*06 

November  

9*55 

10*86 

22*64 

20*00 

17*54 

18*07 

21*85 

In  nine  months  ... 

38*72 

41*29 

74*78 

70*34 

67*27 

67*31 

88*46 

* March  22,  the  gauges  were  free  of  ice ; on  the  31st  they  were  again  frozen  up. 

t Estimated  in  the  same  proportion  as  the  other  months  bear  to  the  valley,  this  gauge  not  being  erected  till 
December  31st,  1846. 


MDCCCXLIX. 


M 


82 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


X 


a 

S3 

r 


’-a 

c 

a 

w 

z 

z 


q; 

-C 

ci 


XJ) 

s 

O) 

s 

0 

1 

s 


bJD 

S 

s 

xn 

'So 

QJ 


OJ 

.o 


O) 

ci 

O) 

'J1 

-M 

o; 


c3 

S 

CL. 

s 

O 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


83 


Note. — The  Lake  District  gauges  are  5 inches  in  diameter  ; they  are  all  of  the  same 
form  and  construction,  and  are  elevated  about  18  inches  above  the  surface.  [During 
1844,  1845  and  part  of  1846,  they  were  raised  only  6 inches  above  the  ground  : in  the 
course  of  the  latter  year  they  were  altered  to  their  present  height.  From  a series  of 
daily  observations  made  in  1847  (vide  Table)  at  Seathwaite,  it  appears  that  at  18  inches 
a gauge  receives  about  2^  per  cent,  less  rain  than  at  6 inches  above  the  surface.] 
The  funnel  rims  are  of  stout  sheet  brass,  so  that  the  apertures  cannot  readily  lose 
their  circular  form.  The  metres  (Howard’s)  were  all  made  by  Mr.  Bate  of  the 
Poultry,  London.  The  rain  (except  at  five  stations)  is  read  off  daily  at  nine  o’clock 
A.M.,  and  each  day  is  accounted  wet  in  which  any  appreciable  deposition  is  found  in 
the  instrument.  The  rain  at  St.  James’s  Church  Steeple,  at  Gatesgarth  and  Eskdale 
Head,  is  measured  weekly;  and  at  Round  Close  and  Gillerthwaite  once  or  twice  a 
month. 

The  gauges  at  and  in  the  vicinity  of  Whitehaven,  are  8 inches  in  diameter,  and 
the  metres  show  distinctly  each  separate  thousandth  of  an  inch. 

Before  concluding  to  use  a gauge  of  5 inches  diameter  for  the  Lake  Districts,  I 
placed  one  of  Howard’s  gauges  in  my  garden,  within  a few  yards  of  the  8-inch  plu- 
viometer, and  measured  the  contents  of  each  every  morning  for  six  months.  From 
the  1st  of  August  1843  to  the  31st  of  January  1844,  the  gauge  of  8-inches  aperture 
received  23*997  inches,  and  the  5-inch  gauge  23*765  inches  I attribute  this  trifling 
difference  to  the  circumstance  of  the  larger  gauge-metre  being  graduated  to  lo^ooth 
of  an  inch,  whilst  the  smaller  only  indicates  xioth,  or  half  a hundredth  of  an  inch. 

Remarks. 

1845. — At  Seathwaite,  there  have  been  thirty-one  days  in  which  the  fall  was  be- 
tween 1 and  2 inches ; fifteen  days  between  2 and  3 inches ; five  days  between  3 and 
4 inches ; one  day  between  4 and  5 inches,  and  one  day  between  6 and  7 inches. 

On  the  27th  of  November,  at  nine  a.m.,  there  was  measured  at  Seathwaite  6*62 
inches,  and  on  the  26th  and  27th  nearly  10  inches,  being  unquestionably  the  greatest 
quantity  of  rain  which  has  ever  been  recorded  in  the  same  period  in  the  British 
Islands. 

At  Langdale  Head,  in  Westmoreland,  the  fall  on  the  27th  was  6*28  inches,  and  on 
the  26th  and  27th  nearly  9 inches. 

On  the  22nd  of  April  1792,  Dr.  Dalton  measured  4*592  inches  at  Kendal,  a re- 
markably wet  locality;  but  I find  on  inquiry  that  the  greatest  fall  at  that  place  in 
twenty-four  hours,  during  the  present  century,  is  rather  short  of  3 inches. 

Of  the  total  quantity  of  rain  measured  in  the  Vale  of  Borrowdale  in  1845,  106*58 
inches  fell  in  the  six  months  of  January,  March,  August,  October,  November  and 
December ; and  nearly  46  inches  in  the  two  latter  months.  The  quantity  in  De- 
cember, at  some  of  the  stations,  is  more  than  falls  at  many  places  in  England  during 
a whole  year. 

The  fall  at  Seathwaite  is  more  than  three  times  the  quantity  at  Whitehaven,  one 

M 2 


84 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


of  the  wettest  towns  in  the  kingdom.  It  exceeds  the  fall  at  Leeds  by  six  times  ; at 
Culloden  by  five  and  a half  times  ; at  Doncaster  and  Highfield  House,  Nottingham- 
shire, by  five  times ; at  Cirencester  and  Arbroath  by  five  and  a quarter  times,  and  at 
Makerstoun  near  Kelso,  by  more  than  seven  times. 

Seathwaite  exceeds  Doncaster  in  January  by  fifteen  times,  in  November  by  twenty- 
one  times,  and  in  December  by  nine  and  a half  times.  It  exceeds  the  quantity  at 
York  in  January  by  16  inches,  or  twenty  times ; in  March  by  nine  times,  and  in  No- 
vember by  twenty  times.  It  exceeds  Dublin  in  March  by  fourteen  times,  in  April  by 
thirteen  times,  in  October  by  five  times,  and  in  November  by  seven  times. 

1S46. — At  Seathwaite  there  have  been  thirty-six  days  in  which  the  quantity  of  rain 
was  between  1 and  2 inches ; six  days  between  2 and  3 inches ; five  days  between 

3 and  4 inches  ; one  day  between  4 and  5 inches,  and  one  day  between  5 and  6 inches. 
At  Langdale  Head  there  have  been  thirty-eight  days  of  the  first,  five  days  of  the 
second,  and  four  days  of  the  third  class ; and  one  day  wherein  the  fall  exceeded 

4 inches.  The  rain  at  Seathwaite  on  the  3rd  and  4th  of  March  amounted  to  6’86 
inches  ; and  on  the  9th  and  10th  of  October  the  fall  was  upwards  of  9 inches. 
On  three  days  of  the  latter  month  there  fell  12T7  inches. 

Of  the  total  fall  of  rain  at  Seathwaite  in  1846  (143‘518  inches),  103’24  inches  fell 
to  the  share  of  January,  February,  March,  July,  August  and  October;  the  other  six 
months  received  much  less  than  in  the  previous  year.  In  November  and  December 
1845,  there  fell  45f  inches  ; in  the  corresponding  months  of  1846,  the  fall  but  slightly 
exceeds  17  inches.  The  table  shows,  that  whilst  the  lake  district  stations  generally 
have  received  more  rain  than  in  1845,  the  deposit  in  the  five  wettest  localities  is 
somewhat  less  than  in  the  previous  year. 

1847. — A glance  at  the  first  table  will  show  that  during  the  year  1847  much  less 
than  an  average  quantity  of  rain  has  fallen*  ; indeed,  had  it  not  been  for  the  enormous 
downfall  in  October,  November  and  December,  the  past  year  would  have  been  one 
of  the  driest  on  record  in  this  part  of  the  country.  At  the  close  of  September  the 
fall  in  the  lake  districts  was  from  one-third  to  one-fourth  less  than  the  average  of  the 
two  preceding  years  : thus,  Seathwaite  was  29‘59  inches,  or  nearly  one-third ; Wast- 
dale  18’76  inches,  or  one-fourth  ; and  Gatesgarth  34*96  inches,  or  more  than  one-third 
short  of  the  average  of  1845  and  1846,  for  the  same  period.  But  the  year  1847  is 
memorable  for  the  remarkable  fact,  that  as  much  or  nearly  as  much  rain  fell  in  the 
last  three  months  as  descended  during  the  other  nine  months  of  the  year.  At  the 
following  stations,  the  quantity  from  October  to  December  inclusive  is  considerably 
more  than  one-half  of  the  whole  annual  depth. 

January  to  October.  October  to  December. 


Buttermere 39*79  42*53 

Gatesgarth 49*97  56*28 

Troutbeck 37'25  40*75 

Stonethw'aite 51*86  54*35 


* With  some  few  exceptions  the  deficiency  appears  to  have  been  general  over  the  kingdom. 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


85 


At  Seathwaite  there  liave  been  thirty-two  days  wherein  the  quantity  of  rain  was  be- 
tween 1 and  2 inches,  five  days  between  2 and  3 inches,  five  days  between  3 and  4 
inches,  one  day  between  4 and  5 inches,  and  one  day  between  5 and  6 inches.  At 
Langdale  Head  there  have  been  thirty  days  of  the  first,  three  days  of  the  second,  and 
five  days  of  the  third  class  (3  to  4 inches). 

There  was  hail  in  the  lake  districts  on  the  8th  of  June  and  on  the  25th  of  July. 
The  last  traces  of  snow  disappeared  from  the  mountains  on  the  1st  of  June,  and  the 
first  appearance  of  hoar  frost  was  on  the  27th  of  September. 

I purposely  postpone  any  remarks  on  the  temperature  of  the  lake  districts  till  the 
next  report,  when  I hope  to  make  some  extensive  comparisons  with  other  and  widely 
different  localities.  The  temperature  of  these  valleys  is  much  higher  than  is  com- 
monly imagined.  The  observations  both  in  1846  and  1847  were  taken  with  great 
care,  and  I have  no  doubt  of  their  correctness.  The  radiation  from  the  earth  is 
much  greater  in  summer  than  at  the  coast ; but  in  winter  it  appears  to  be  so  ex- 
ceedingly small,  that  I have  thought  it  best  to  omit  the  results  for  those  months  in 
the  table  till  future  observations  have  proved  their  accuracy  or  otherwise. 

The  Mountain  Gauges. 

The  mountain  gauges  are  on  pretty  much  the  same  construction  as  those  in  the 
valleys,  but  the  receivers  are  much  more  capacious,  being  calculated  to  hold  nearly 
80  inches  of  water.  These  gauges  are,  with  one  exception,  stationed  on  the  high 
mountains  surrounding  the  vale  of  Wastdale. 

Sea  Fell,  the  highest  mountain  in  England,  stands  on  the  south,  and  Great  Gable 
on  the  north  side  of  the  valley.  The  gauge  above  Stye  Head  Tarn  is  on  the  shoulder 
of  the  Gable  at  the  eastern  extremity  of  the  vale : Sparkling  Tarn  is  about  600  feet 
above  the  top  of  Stye  Head  Pass,  in  a southerly  direction,  and  1260  feet  higher,  bear- 
ing south-west,  are  Sea  Fell  Pikes. 

The  bearings  of  the  several  stations  from  the  gauge  at  Wastdale  Head  are  as  fol- 
low:— Sea  Fell,  S.;  Gable,  N.N.E. ; Stye  Head,  N.E. ; Sparkling  Tarn,  E.  by  N.;  and 
Seatollar  Common  in  Borrowdale,  N.E.,  distant  four  and  a half  miles  in  a direct  line. 

The  gauges  on  Sea  Fell,  Gable  and  Seatollar,  are  on  the  extreme  summits  of  these 
mountains,  and  the  whole  of  the  instruments  are  freely  exposed  to  the  action  of  wind 
and  rain  from  almost  every  point  of  the  compass. 

Appended  to  the  tables  for  1846  I find  the  following  remark  : — “It  would  be  pre- 
mature,  from  the  scanty  data  before  me,  to  draw  any  decided  inference  as  to  the  gra- 
dation in  the  quantity  of  rain  at  these  great  elevations  above  the  sea.  But  it  seems 
probable  that  in  mountainous  districts  the  amount  of  rain  increases  from  the  valley 
upwards,  to  an  altitude  of  about  2000  feet,  where  it  reaches  a maximum ; and 
that  above  this  elevation  it  rapidly  decreases.”  The  Table  for  1846  exhibited  the 
rain-fall  of  the  summer  months  only,  but  the  additional  returns  of  1847,  obtained  in 
every  variety  of  season,  confirm  the  above  deductions  in  every  essential  particular. 


86 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


SO  that  we  may  fairly  assume  the  combined  results  to  be  indicative  of  a physical  law, 
so  far  at  least  as  relates  to  the  particular  locality  in  question.  Thus,  in  twenty-one 
months, 


The  Valley  . . 

160  feet  above  the  sea,  has  received 

170'55  inches. 

8tye  Head  . . . 

. 1290 

55  5’ 

18574  „ 

Seatollar  Common 

. 1334 

?5 

180-23*  „ 

Sparkling  Tam 

. 1900 

35  33 

207-91 

Great  Gable  . . 

. 2925 

55  35 

136-98 

Sea  Fell  .... 

. 3166 

55  55 

128-15 

An  apparent  exception  to  this  law  occurs  in  the  gauge  stationed  at  Brant  Rigg,  about 
midway  between  the  top  of  Stye  Head  and  the  vale  of  Wastdale,  at  an  estimated 
height  of  500  feet  above  the  sea,  and  which  in  last  year  has  received  about  one- 
eighth,  or  twelve  and  three  quarters  per  cent,  less  rain  than  the  valley.  This  is  the 
only  one  of  the  gauges  situated  on  the  slope  of  a mountain  ; it  is  on  the  windward 
side,  and  I imagine  that  in  such  a position,  eddies  or  counter  currents  are  produced 
in  windy  weather,  which  cause  a less  quantity  of  water  to  be  deposited  in  the  instru- 
ment than  is  due  to  the  elevation.  We  know^  that  all  sloping  roofs,  from  the  same 
cause,  materially  diminish  the  receipts  of  rain-gauges. 

It  will  be  observed  that  the  amount  of  water  received  by  the  Seatollar  gauge  is 
invariably  less  than  the  deposit  in  the  adjacent  vale  of  Seathwaite,  and  the  deficiency 
is  pretty  equable  in  every  month  of  the  year.  I am  unable  to  give  any  satisfactory 
reason  for  this  apparent  anomaly,  or  to  account  for  the  very  great  excess  of  rain  in 
this  valley  over  all  others  in  the  lake  districts.  As  the  gauge  on  Seatollar  is  two  or 
three  miles  distant  in  a direct  line  from  the  others,  the  near  approach  of  its  receipts 
to  the  Stye  Head  gauge,  about  the  same  elevation,  is  rather  remarkable.  In  1846 
the  Seatollar  exceeded  the  Stye  gauge  in  quantity,  which  it  should  do  if  the  assumed 
height  be  correct. 

By  referring  to  the  table  for  the  summer  months,  we  find  that  between  the  1st  of 
May  and  the  31st  of  October,  the  gauge  at  1290  feet  has  obtained  nearly  twelve  per 
cent,  more  rain  than  the  valley;  at  1334  feet,  nine  and  a half  per  cent,  more;  at 
1900  feet,  twenty-nine  per  cent,  more;  at  2928  feet,  seven  and  a half  per  cent,  less-, 
and  at  3100  feet,  thirteen  and  a half  per  cent,  less  than  the  valley. 

In  the  winter  months  (November  to  April  inclusive)  the  gauge  at  1290  feet  has 
received  four  and  a half  per  cent,  more  than  the  valley,  and  at  1334  feet  exactly  the 
same  quantity  as  the  valley;  at  1900  feet,  eleven  and  a quarter  per  cent,  more;  at 
2928  feet,  thirty-eight  and  a half  percent,  less ; and  at  3100  feet,  forty-two  and  a half 
per  cent,  less  than  the  valley.  The  difference  in  the  proportion  to  the  valley  between 
the  summer  and  winter  half-year,  as  shown  in  the  tables,  is  rather  startling.  When 
much  snow  falls,  doubtless  a considerable  proportion  is  lost  to  the  instrument,  either 


* The  height  of  Seatollar  Common  has  not  been  correctly  ascertained. 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


87 


by  its  being  blown  out  of  the  funnel,  or  by  the  orifice  getting  choked  up.  But  I do 
not  think  that  this  cause  alone  is  at  all  adequate  to  account  for  the  great  compara- 
tive deficiency  in  the  winter  months,  for  there  was  very  little  snow  on  the  mountain 
tops  during  the  winter  of  1846-4/,  less  I am  told  by  one  of  the  oldest  residents  in 
the  Fell  Dales,  than  he  almost  ever  remembers.  At  Whitehaven  we  had  no  snow 
worth  naming,  except  on  the  night  of  the  23rd  of  December,  when  it  covered  the 
ground  to  the  depth  of  nearly  an  inch,  but  disappeared  in  the  course  of  the  ensuing 
morning. 

The  late  Mr.  Crosthwaite  of  Keswick,  by  means  of  marks  on  the  side  of  Skiddaw, 
and  with  the  assistance  of  a telescope  at  his  residence,  made  two  or  three  daily  ob- 
servations on  the  height  of  clouds  for  several  years,  and  it  is  clearly  proved  by  his 
tables,  that  the  clouds  are  lowest  in  the  three  first  and  three  last  months  of  the  year*. 
Moreover,  Dr.  Dalton  affirms  in  his  “ Meteorology,”  that  the  clouds  are  seldom  a 
mile  high  (or  little  more  than  1^  time  the  altitude  of  Sea  Fell)  in  this  climate  in 
winter.  Now  the  Doctor  here  probably  alludes  to,  or  at  least  includes,  the  most 
elevated  clouds,  such  as  the  cirri,  and  some  varieties  of  the  cirrostratus.  But  there 
can  be  no  doubt,  that  between  the  months  of  November  and  March,  the  under  surface 
of  the  nimbus  or  rain-cloud  (the  lowest  except  the  stratus)  is  far  below  the  tops  of 
our  highest  mountains,  and  I have  reason  to  believe,  not  unfrequently,  its  upper  surface 
also  : when  this  is  the  case,  the  gauges  on  Sea  Fell,  Gable,  &c.  will  receive  no  rain 
at  all,  when  it  is  descending  abundantly  in  the  valleys  beneath.  I have  a well-authen- 
ticated instance  of  such  an  occurrence,  even  in  the  middle  of  summer.  On  the  5th 
of  July  1846  (the  hottest  day  in  the  year)  this  county  was  visited  by  a dreadful  storm 
of  thunder,  lightning,  hail  and  rain,  which  continued  from  two  to  half-past  four  o’clock 
in  the  afternoon.  Two  gentlemen  who  happened  to  be  on  the  top  of  Skiddaw  during 
this  storm,  state  that,  whilst  the  rain  was  pouring  down  in  torrents  in  the  valley,  not 
a drop  fell  on  the  summit  of  the  mountain.  In  this  elevated  position  the  sky  was 
clear,  and  the  atmosphere  calm  and  untroubled,  when  below  them  the  elemental  war 
was  raging  with  the  most  terrific  fury.  The  spectators  describe  the  scene  as  awfully 
grand,  beyond  conception.  The  lowness  of  the  rain-cloud  at  this  season  is,  I appre- 
hend, the  principal  cause  of  the  small  quantity  of  rain  in  proportion  to  the  valley, 
during  the  winter  as  compared  with  the  summer  months. 

I shall  conclude  this  paper  with  a few  general  remarks. 

In  the  year  1836  or  1837,  Mr.  Beck  of  Esthwaite  Lodge,  about  two  miles  to  the 
westward  of  Windermere  Lake,  began  to  register  the  amount  of  rain  in  that  neigh- 
bourhood, and  between  1837  and  1844,  the  annual  quantity  varied  from  60  to 
86  inches.  In  1843,  Mr.  Jefferies  obtained  90  inches  at  Grasmere.  The  results 
at  Esthwaite  and  Grasmere  were  received  with  astonishment  by  meteorologists, 
not  unaccompanied  by  some  degree  of  suspicion  as  to  their  correctness.  Indeed  it 
was  with  the  view  of  removing  all  doubt  on  the  matter,  that  in  the  year  1844  I was 

* Dalton’s  Meteorology,  1796. 


88 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


induced  to  begin  the  present  series  of  experiments  on  rain  amongst  the  hills  of  Cum- 
berland. Yet  90  inches  would  now  be  thought  a small  quantity  for  some  parts  of  the 
Lake  District,  even  in  a year  of  drought ! ! 

I am  frequently  asked  by  persons  unacquainted  with  such  matters,  what  beneficial 
end  I expect  such  a series  of  experiments  to  lead  to,  and  what  information  I have 
gained  in  return  for  my  loss  of  time  and  trouble.  To  this  question  1 may  reply,  they 
have  shown  us,  that  at  least  60  inches  more  rain  is  deposited  in  England  than  we 
were  previously  aware  of ; that  150  inches  sometimes  descends  in  the  Lake  District 
in  a year,  more  than  falls  in  most  parts  of  the  tropics  with  which  we  are  acquainted, 
and  sufficient  to  drown  standing,  two  of  the  tallest  men  in  Great  Britain,  one  on  the 
top  of  the  other.  They  have  further  informed  us,  that  6^  perpendicular  inches  of 
water  is  sometimes  precipitated  from  the  atmosphere  in  twenty-four  hours,  and  10 
inches  in  forty-eight  hours,  a quantity  which  would  be  thought  large  for  any  two 
consecutive  months  in  most  parts  of  England.  We  have  further  ascertained  that  the 
almost  incredible  depth  of  30  inches  occasionally  descends  in  a single  month  ; a 
fall  nearly  equal  to  the  calculated  average  for  all  other  parts  of  England  in  a year*. 
The  experiments  have,  in  short,  enabled  us  to  collect  a number  of  new  and  curious 
facts,  bearing  on  the  quantity  and  very  unequal  distribution  of  rain  in  this  island. 
We  have  also  ascertained,  with  a high  degree  of  probability,  the  law  of  the  gradation 
in  the  amount  of  rain,  at  various  intermediate  points,  between  the  valleys  and  the 
tops  of  our  highest  mountains. 

A little  consideration  will  greatly  lessen  our  surprise  at  the  enormous  quantities 
of  water  deposited  in  the  hilly  districts  of  Cumberland  and  Westmoreland,  and  at 
the  consequent  unequal  distribution  of  rain  in  the  climate  of  Great  Britain.  To  those 
unacquainted  with  these  localities,  it  may  be  briefly  stated,  that  the  lake  district 
valleys  radiate  from  a series  of  mountains  of  slate  and  pritnitive  rock,  having  the 
Gable,  2928  feet  in  height,  as  a nucleus  or  central  point,  and  in  the  immediate 
vicinity  of  which  are  Sea  Fell  and  Pillar,  of  the  respective  elevations  of  3166  and 
2893  feet ; and  Great  End,  Bowfell  and  Glaramara,  not  much  inferior  in  altitude. 
These  mountains  are  distant  only  about  thirteen  or  fifteen  miles,  in  a direct  line  from 
the  Irish  Channel,  and  as  no  hills  intervene,  they  are  consequently  fully  exposed  to 
our  wet  and  prevailing  winds,  which  are  the  south-west. 

The  warm  south-westerly  current  arrives  at  the  coast  loaded  with  moisture  obtained 
in  its  transit  across  the  Atlantic  : now  our  experiments  justify  us  in  concluding,  that 
this  current  has  its  maximum  density  at  about  2000  feet  above  the  sea  level ; hence 
it  will  travel  onward  until  it  is  obstructed  by  land  of  sufficient  elevation  to  precipitate 
its  vapour ; and  retaining  a portion  of  the  velocity  of  the  lower  parallel  of  latitude 
whence  it  was  originally  set  in  motion,  it  rapidly  traverses  the  short  space  of  level 

* This  astonishing  quantity  fell  at  Seathwaite  in  February  1 848,  in  twenty-five  days,  on  several  of  which 
the  amount  was  very  trifling.  The  gauge  at  6 inches  above  the  surface  received  30'55  inches,  and  that  at 
18  inches  29'98,  or  30  inches  nearly. 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


89 


country,  and  with  little  diminution  of  its  weight  or  volume ; but  on  reaching  the 
mountains,  it  meets  with  a temperature  many  degrees  lower  than  the  point  at  which 
it  can  continue  in  a state  of  vapour ; sudden  condensation  consequently  ensues  in 
the  form  of  vast  torrents  of  rain,  which  in  some  instances  must  descend  almost  in 
a continuous  sheet,  as  when  9 or  10  inches  are  precipitated  in  forty-eight  hours. 

When  we  reflect  that  a warm  moist  current,  perhaps  only  3°  or  4°  above  the  point 
of  saturation,  in  coming  in  contact  with  the  mountain  ridge,  probably  meets  with  a 
stratum  of  air  10°  or  15°  lower  than  its  own  inherent  temperature,  we  shall  cease  to 
marvel  that  such  quantities  as  four  or  five,  or  even  six  perpendicular  inches  of  water 
should  be  deposited  in  these  localities  in  the  course  of  a few  hours.  The  mountains 
are,  in  fact,  huge  natural  condensers,  destined  to  force  from  the  atmosphere  the 
mighty  volumes  of  water  requisite  for  the  supply  of  our  lakes  and  rivers. 

I have  before  stated  that  I am  unable  to  offer  any  satisfactory  reason  for  the  great 
excess  of  rain  at  Seathwaite  over  all  the  other  valleys ; judging  from  its  situation,  I 
should,  a 'priori,  have  looked  for  the  greatest  fall  at  Wastdale  Head,  as  it  is  sur- 
rounded by  the  highest  mountains,  and  the  valley  opens  out  fairly  to  the  south-west. 
But  the  maximum  quantity  is  found  to  obtain,  not  where  theory  would  indicate,  but 
in  the  very  identical  spot  where  it  is  most  required, — in  the  vale  of  Borrowdale,  which 
affords  the  principal  supply  of  water  to  the  extensive  and  picturesque  lakes  of  Der- 
went and  Bassenthwaite  ; thus  adding  one  more  to  the  multitudinous  instances  which 
surround  us,  of  the  wonderful  adaptation  of  external  nature  to  the  physical  wants 
and  requirements  of  man. 


Whitehaven,  March  15,  1848. 


MDCCCXLIX. 


N 


[ M ] 


\'ni.  An  Investigation  on  the  Chemical  Nature  of  Wax. 

By  Benjamin  Collins  Brodie,  Esq. 

Communicated  hy  Sir  Benjamin  C.  Brodie,  Bart.,  F.R.S.  8§c. 

Received  May  11, — Read  November  23,  1848. 

III.  On  Myricin. 

I HAVE  placed  the  investigation  of  the  Chinese  wax  between  that  of  the  cerotic 
acid  and  of  the  residue  of  the  bees’-wax  which  remains  after  that  substance  has  been 
separated  from  it.  By  the  saponification  of  this  Chinese  wax  we  procure,  as  I have 
shown,  an  acid  identical  with  the  cerotic  acid  from  bees’-wax,  and  also  the  alcohol 
of  this  acid,  so  that  the  chemical  history  of  these  substances  is  closely  connected. 
We  have  moreover  in  the  Chinese  wax  to  deal  with  a substance  found  in  nature  in  a 
state  of  great  purity,  the  products  of  the  decomposition  of  which  by  alkalies  and  by 
heat  can  readily  be  prepared  and  examined.  The  knowledge  of  the  relation  of  these 
products  to  one  another  throws  great  light  upon  the  nature  of  myricin,  which  is  not 
a pure  substance,  and  the  chemical  relations  of  which  are  complex. 

I have  stated  that  the  first  extracts  of  wax  with  alcohol  give  with  acetate  of  lead 
an  abundant  precipitate  in  a hot  alcoholic  solution.  This  affords  us  a ready  test  of 
the  presence  of  the  cerotic  acid.  The  wax  may  be  long  boiled  with  alcohol  before 
the  whole  of  the  cerotic  acid  is  removed.  If  however  this  process  of  boiling  and 
decantation  be  continued,  a time  will  come  when  the  acetate  of  lead  will  cease  to 
give  any  precipitate  whatever  in  the  hot  alcoholic  extract.  I'he  residue  after  this 
extraction  I speak  of  as  myricin.  It  is  advisable  to  continue  for  two  or  three  times 
the  operation  of  boiling  and  decanting,  even  after  the  acetate  gives  no  precipitate, 
the  cerotate  of  lead  not  being  entirely  insoluble  in  the  hot  solution. 

The  myricin  thus  prepared  is  a greenish  substance  of  about  the  consistency  of  wax, 
uncrystalline,  still  possessing  a slight  smell  of  wax,  and  of  a melting-point  of  64°  C. 
This  substance  is  hardly  acted  on  by  dilute  potash.  It  is  however  saponified  by 
boiling  with  strong  potash,  and  more  readily  by  an  alcoholic  solution  of  the  alkali. 
The  saponification  may  also  be  effected  by  melting  it  with  hydrate  of  potash,  as  in 
the  case  of  the  Chinese  wax.  The  products  are  the  same  in  whichever  way  the 
operation  be  conducted. 

If  the  soap  from  the  saponifieation  of  the  myricin  be  treated  in  the  same  manner 
as  the  similar  soap  from  the  Chinese  wax*,  it  also  will  be  found  to  contain  two  sub- 
stances, an  acid  and  another  substance  which  is  contained  in  the  ether  with  which 
the  baryta  salt  is  extracted.  On  attempting  to  purify  these  substances  respectively 

* Philosophical  Transactions,  1848,  Part  I.  p.  161. 

N 2 


92 


MR.  BRODIE  ON  xMYRICIN. 


by  crystallization  out  of  alcohol,  ether  or  absolute  alcohol,  great  variations  in  the 
melting-point  both  of  the  acid  and  of  the  basic  substance  will  be  observed.  And 
careful  observation  shows  that  these  are  not,  as  in  the  case  of  the  Chinese  wax,  sub- 
stances in  a state  of  comparative  chemical  purity,  but  are  mixtures,  both  in  the  case 
of  the  acid  and  of  the  other  matter,  of  at  least  two  bodies  difficultly  separable  from 
one  another.  It  is  the  separation  of  these  substances  which  gives  a peculiar  difficulty 
to  the  investigation  of  the  nature  of  myricin. 

Although  the  acid  and  basic  products  of  the  saponification  may  thus,  as  in  the 
case  of  the  Chinese  wax,  be  separated  by  precipitation  of  the  soap  by  a baryta  salt, 
in  the  case  of  the  bees’- wax  these  substances  admit  of  a simpler  method  of  separation, 
Avithout  which  method,  so  difficult  is  it  to  wash  perfectly  out  the  baryta  salt,  that  I 
question  whether  the  substances  could  be  obtained  pure.  The  soap,  in  whatever 
way  the  saponification  may  have  been  effected,  and  after  the  alcohol,  if  any,  used  for 
the  saponification  has  been  distilled  off,  is  to  be  dissolved  in  a large  quantity  of  water, 
and  the  boiling  solution  decomposed  by  an  acid.  The  melted  mass  which  results 
from  this  operation,  after  having  been  repeatedly  boiled  out  with  water,  is  to  be  dis- 
solved in  a large  quantity  of  hot  alcohol.  An  abundant  precipitate  appears  in  the 
cold  fluid  from  which  the  solution  is  to  be  filtered,  and  the  precipitate  repeatedly 
redissolved  and  recrystallized  out  of  alcohol.  The  precipitate  will  at  length  be  found 
to  consist,  almost  entirely,  of  the  basic  portion  of  this  waxy  matter.  The  alcoholic 
solution  contains  the  acid. 

I shall  proceed  to  give  the  simplest  method  by  which  the  pure  substances  may  be 
obtained,  and  those  experiments  which  I have  made  upon  their  constitution,  which 
I think  can  leave  no  doubt  upon  the  mind  of  the  chemist  as  to  the  true  nature  of 
that  matter  of  which  by  far  the  greater  portion  of  the  myricin  and,  indeed,  of  the 
wax  itself  consists. 

The  first  separation  of  the  products  of  saponification  may  be  made  as  I have 
stated,  by  combining  the  acid  with  baryta  and  washing  out  the  resulting  salts  with 
ether ; the  basic  portion  of  the  products  may  be  obtained  as  pure  by  this  as  by  the 
other  method. 


Melissin. 

If  the  substance  contained  in  the  etherial  solution,  With  which  the  baryta  salt  is 
washed  out,  be  crystallized  out  of  ether  or  alcohol,  the  melting-point  will  be  con- 
siderably raised,  from  below  70°  C.  to  above  80°,  by  repeated  crystallization.  The 
difficulty  with  which  the  melting-point  was  raised,  made  it  evident  that  the  substances 
contained  in  the  solution  were  to  be  separated  only  by  long  crystallization  and  a 
careful  attention  to  the  variations  of  the  melting-points.  I made  various  experiments 
to  discover  a satisfactory  method  of  purification.  At  length  I found  that  if  the 
etherial  solution  be  filtered  while  yet  warm,  and  when  only  a small  portion  of  matter 
has  crystallized  out,  a substance  remains  on  the  filter  of  a melting-point  of  85°  C. 
of  a satiny  lustre,  and  of  highly  crystalline  appearance.  It  is  with  difficulty  that 


MR.  BRODIE  ON  MYRICIN. 


93 


even  a small  portion  of  substance  can  be  thus  obtained,  and  it  is  necessary  to  use, 
during  the  filtration,  a hot  water  apparatus  to  prevent  the  precipitation  of  the  whole 
matter  dissolved.  I have  never  been  able  to  succeed  in  further  raising  the  melting- 
point  of  this  body,  and  therefore  regard  it  as  pure.  In  this  condition  it  crystallizes 
on  cooling  from  the  melted  state,  and  its  crystallization  is  marked  by  striae  parallel 
to  the  line  of  cooling ; it  being  in  all  respects,  but  the  melting-point,  similar  in  ap- 
pearance to  cerotin  as  procured  from  Chinese  wax. 

I give  this  method  of  preparing  this  substance  as  it  was  the  first  I adopted,  and 
as  it  can  thus  be  procured  in  a high  state  of  purity.  I afterwards  however  disco- 
vered the  use  of  rectified  coal  naphtha  as  a solvent  for  these  substances,  and  by  far 
the  best  and  simplest  method  of  procuring  the  body  is  by  crystallization  out  of  that 
solvent,  of  the  precipitate  from  the  alcoholic  solution  which  I have  before  mentioned, 
as  procured  by  dissolving  in  alcohol  the  wax  matter  obtained  by  decomposing  by  an 
acid  the  soap  from  the  myricin.  By  alcohol  the  basic  portion  of  the  saponified  rnyricin 
is  separated  from  the  acids.  By  naphtha  the  substance  of  85°  melting-point  is  sepa- 
rated from  another  and  probably  an  analogous  body,  of  which  I shall  speak  hereafter. 

This  substance  gave  to  analysis  the  following  numbers.  The  result  is  the  same  in 
whatever  way  the  substance  is  prepared. 


Substance. 

CO,. 

HO. 

I.  0*2685  grm.  gave  . . 

. . 0*8075 

0*341 

II.  0*2597  grm.  gave  . . 

. . 0*7839 

0*3326 

III.  0*278  grm.  gave  . . 

. . 0*84375 

0*35325 

IV.  0*2584  grm.  gave  . . 

. . 0*7812 

0*325 

V.  0*251 1 * grm.  gave 

. . 0*7595 

0*3215 

VI.  0*261 7 "1“  grm.  gave  . 

. . 0*7870 

0*3295 

which  give 

in  100  parts — 

I.  11. 

III.  IV. 

V. 

VI. 

Carbon 

82*02  82*40 

82*77  82*43 

82*48 

82*01 

Hydrogen 

14*11  14*25 

14*11  13*97 

14*22 

13*99 

Oxygen 

3*87  3*35 

3*12  3*60 

3*30 

4*00 

100*00  100*00 

100*00  100*00 

100*00 

100*00 

These  analyses  agree  with  the  formula— 

Atomic  weight. 

Calculated. 

^60 

. . 360 

82*19 

H62  . 

. . 62 

14*15 

O2  . 

. . 16 

3*66 

438 

100*00 

This  substance  I propose  to  call  Melissin. 

* This  substance  was  procured  directly  from  wax,  from  which  it  may  be  obtained  and  purified  in  the  same 
manner  as  from  the  purified  myricin ; which  is  the  simplest  way  of  procuring  the  substance  if  the  other  pro- 
ducts of  saponification  are  not  required. 

t This  substance  was  procured  from  the  Ceylon  wax  mentioned  in  a former  paper. 


94 


MR.  BRODIE  ON  MYRICIN. 


Melissic  Acid. 

Melissin,  heated  with  lime  and  potash,  as  the  similar  experiment  was  made  with 
cerotin*,  is,  like  that  body,  converted  into  an  acid.  This  acid  has  a similar  appear- 
ance to  the  wax  acid  already  described.  It  has  however  a much  higher  melting-point, 
namely,  88°-89°  C.  The  preparation  of  the  substance  need  not  be  again  described. 

CO2.  HO. 

I.  0‘2655  grm.  gave 07764  0*3104 

II.  0*2507  grm.  gave  (another  preparation)  . 0*728  0*2507 

III.  0*2508  grm.  gave 0*7333  0*3077 

JV.  0*2396  grm.  gave  (another  preparation)  . 0*7026  0*2885 

V.  0*258  grm.  gave 0*3085 

which  give  in  100  parts — 


I.  II. 

III. 

IV.  V. 

Carbon  ....  79*74  79*19 

79*74 

79*97 

Hydrogen  . . . 13*00  ’13*32 

13*63 

13*40  13*28 

Oxygen  ....  7'26  7'49 

6*63 

6*63 

100*00  100*00 

100*00 

100*00 

These  analyses  agree  with  the  formula — 

Atomic  weight. 

Calculated. 

CgQ  . . . 360 

79*64 

Heo  . . . 60 

13*27 

O4  ...  32 

7*09 

452 

100*00 

I prepared  the  silver  salt  of  this  acid  in  precisely  the  same  manner  as  was  prepared 

the  silver  salt  of  the  cerotic  acid. 

I.  0*6085  grm.  gave 

. 0*1175  silver. 

II.  0*678  grm.  gave 

. 0*1315  silver. 

III.  0*58625  grm.  gave  (another  preparation)  . 

. 0*1 1575  silv'er. 

which  give  in  100  parts — 

I. 

II. 

HI. 

Silver 19*30 

19*39 

19*74 

CO„.  HO. 

I.  0*4619  grm.  of  the  salt  gave  . . 

. . 1*0863  0*4464 

II.  0*484  grm.  of  the  salt  gave  . . 

. . 1*13375  0*471 

giving  in  100  parts — 

I. 

II. 

Carbon 

. 64*13 

63*90 

Hydrogen 

. 10*73 

10*81 

Oxygen  and  silver 

. 25*14 

25*29 

100*00 

100*00 

* Philosophical  Transactions,  1848,  Part  I.  p.  161. 


MR.  BRODIE  ON  MYRICIN. 


95 


These  analyses  lead  to  the  formula  Cgg  H59O4  Ag. 


Calculated. 

Cgo  .... 

64*38 

H59  .... 

10*55 

O4  .... 

377 

Ag  .... 

19*30 

100*00 

The  formula  therefore  of  the  hydrated  acid  is  Cgg  Hgg  O4.  This  acid  I call  Melissic 
Acid. 

Chlor-Melal. 


By  the  action  of  chlorine  on  melissin  a perfectly  analogous  result  is  obtained  to 
that  obtained  by  the  action  of  chlorine  on  cerotin.  The  substance  undergoes  also  a 
similar  change  in  appearance,  being  converted  into  a resin. 

The  substance  was  prepared  and  analysed  with  a view  to  confirming  the  formula 
of  the  body. 

I.  0*4136  grm.  gave  . . 

II,  0*4263  grm.  gave 
which  give  in  100  parts — 

Carbon 


Oxygen  and  chlorine 


CO,. 

HO. 

0*589 

0*175 

0*602 

0*1835 

I. 

II. 

. . 38*83 

38*51 

. . 4*70 

4*78 

. . 56*47 

56*71 

100*00 

100*00 

I.  0*6663  grm.  gave  1*4821  grm.  of  chloride  of  silver  equivalent  to  0*3665  grm.  of 
chlorine. 

II.  0*6075  grm.  gave  1*341  grm.  of  chloride  of  silver  equivalent  to  0*3316  grm.  of 
chlorine. 

III. .  0*6475  grm.  gave  1*4375  grm.  of  chloride  of  silver  equivalent  to  0*3555  grm. 
of  chlorine. 

These  determinations  correspond  in  100  parts  to — 

I.  II.  III. 

Chlorine 55*01  54*58  54*91 

These  analyses  lead  to  the  formula 


^60  j 

r ^45*5 

1 '-'2- 

^60  • • 

. . . 38*50 

H454  . 

. . . 4*86 

di44  • 

. . . 54*90 

O2.  . 

. . . 1*74 

100*00 

As  in  the  case  of  the  cerotin,  by  the  action  of  chlorine  two  equivalents  of  hydrogen 
are  removed  without  replacement  by  chlorine,  while  the  further  action  is  an  action 
of  substitution,  the  substance  being  the  analogue  of  chloral. 


96 


MR.  BRODIE  ON  MYRICIN. 


The  products  of  the  distillation  of  melissin  are  analogous  to  those  of  the  distillation 
of  cerotin.  The  substance  partly  distils  over  unaltered,  and  is  partly,  with  the  loss 
of  water,  converted  into  solid  hydrocarbon.  Sulphuric  acid  also  combines  with  it 
under  the  same  conditions  as  with  the  other  wax-alcohol. 

Palmitic  Acid  from  the  Saponification  of  Myricin. 

Melissin  is  soluble  with  such  great  difficulty,  in  every  solvent  suitable  for  washing 
out  the  baryta  salt  from  the  wax  soap,  that  its  separation  from  the  acid  cannot  in 
this  manner  be  effected.  It  may  however  be  separated  by  simple  crystallization. 
The  alcoholic  solution  (p.  278)  from  which  the  melissin  has  crystallized  out,  after 
having  been  considerably  concentrated  and  again  filtered  from  any  precipitate  pro- 
duced on  cooling,  contains  hardly  a trace,  if  any,  of  that  substance.  The  acids  are 
very  soluble  in  alcohol,  and  it  is  only  on  great  concentration  that  they  crystallize 
from  that  solvent.  The  alcohol  is  to  be  distilled  off  to  the  point  of  crystallization, 
and  the  first  portions  only  of  the  fat  acid  selected  for  the  preparation  of  the  pure 
substance.  The  acid  is  to  be  boiled  with  potash,  combined  with  baryta,  and  washed 
out  with  ether. 

On  decomposing  the  baryta  salt  with  hydrochloric  acid,  a fat  acid  separates,  having 
the  appearance  of  margaric  or  palmitic  acid,  which  latter  body  is  in  truth  the  prin- 
cipal acid  of  the  wax.  It  is  however  mixed  with  another  acid  of  a lower  melting- 
point,  for  which  reason  it  is  desirable,  as  I have  mentioned,  to  use  in  its  preparation 
only  the  first  crystallization  of  the  acid.  From  this  other  body  it  is  separable  with 
the  greatest  difficulty  ; but  by  long-continued  crystallization  from  ether,  an  acid 
may  be  obtained  of  the  melting-point  of  62°  C.,  beyond  which  point  it  cannot  be 
raised.  This  acid  gave  to  analysis  the  following  results : — 


CO^. 

HO. 

I.  0'2486  grm.  gave 

0*6877 

0*278 

II.  0*2605  grm.  gave 

0*7145 

0*290 

III.  0*2542  grm.  gave 

0*6937 

0*2847 

giving  per  cent. — 

I. 

II. 

III. 

Carbon 75’42 

74*80 

74*43 

Hydrogen 12*43 

12*36 

12*43 

Oxygen 12*15  ' 

12*84 

12*14 

100*00 

100*00 

100*00 

The  silver  salt  was  made  as  in  the  other  cases 

by  precipitation  from  the  ammo- 

niacal  solution  of  the  acid. 

I.  0*6885  grm.  of  this  salt  gave  . . 

. 

0*2005  silver. 

II.  0'66025  grm.  of  the  same  gave  . 

. 

0*1920  silver. 

III.  0*623  grm.  of  anotlier  preparation  gave  . 

0*182  silver. 

IV.  0*609  grm.  of  the  same  gave  . 

. 

0*17625  silver. 

V.  0*671  grm.  of  another  preparation  gave  . 

0*197  silver. 

VI.  0*744  grm.  of  the  same  gave  . 

. 

0*2185  silver. 

MR.  BRODIE 

ON  MYRICIN. 

97 

giving  in  100  parts — 

I.  II.  III. 

IV. 

V. 

VI. 

29-12  29-23  29-21 

28-94 

29-35 

29-36 

CO,. 

HO. 

I.  0-4458  grm.  of  the  first  preparation  gave  . . 

. 0-869 

0-3495 

II.  0-4463  grm.  of  the  same  preparation  gave 

. 0-870 

0-3555 

III.  0-5896  grm.  of  the  second  preparation  gave  . 

. 0-7545 

0-3065 

which  correspond  in  100  parts  to — 

I. 

II. 

III. 

Carbon 

53-16 

53-22 

52-82 

Hydrogen 

. 8-70 

8-85 

8-75 

Silver  and  oxygen  .... 

. 38-14 

37-93 

38-43 

100-00 

100-00 

100-00 

The  silver  salt  is  by  no  means  insoluble 

in  the  ammoniacal  solution,  so  that  in 

the 

making  of  the  salt  by  this  method  a certain  separation  of  the  substance  is  effected. 
If  any  impurity  were  presented,  it  probably  would  be  detected  on  analysing  the  acid 

as  again  separated  from  the  silver  salt. 

CO,. 

HO. 

I.  0-2523  grm.  of  the  acid  thus  separated  gave 

. 0-6970 

0-285 

II.  0-228  grm.  of  the  same  gave  . 

. 0-6255 

0-257 

giving  in  100  parts 

I. 

II. 

Carbon 

. . 75'38 

74-82 

Hydrogen 

. . 12-56 

12-52 

Oxygen 

. . 12-06 

12-66 

100-00 

100-00 

These  analyses,  as  well  as  those  of  the  acid  previous  to  combination  with  silver, 
agree  with  the  formula  of  palmitic  acid,  C32  H32  O4,  with  which  substance  the  melt- 
ing-point of  the  acid  also  identifies  it.  The  calculated  numbers  in  parts  per  cent,  of 
the  acid  and  silver  salt  are — 


C32  • 

....  192  . 

. . 75*0 

H32. 

....  32  . 

. . 12-5 

O4  . 

....  32  . 

. . 12-5 

256 

100-0 

C32  • 

....  192 

. . 52-8 

H31. 

....  31 

. . 8-5 

O4  . 

....  32  . 

. . 9-0 

Ag  . 

....  108-1  . 

. . 29-7 

363-1 

100-0 

MDCCCXLIX. 


o 


98 


MR.  BRODIE  ON  MYRICIN. 


Dutillation  of  Myricin. 

The  discovery  of  the  cerotic  acid  rendered  it  evident  that  in  order  to  obtain  the 
products  of  distillation  of  myricin,  and  especially  the  acids  in  a state  of  purity,  it  was 
necessary  first  to  remove  that  body  and  to  distil  only  the  residue  of  the  wax.  I give 
the  results  of  this  experiment  made  with  myricin.  The  first  portions  of  the  distillate 
consist  almost  entirely  of  acids,  the  latter  of  hydrocarbons.  During  the  distillation 
a smell  of  butyric  acid  may  be  perceived.  This  however  appeared  to  me  to  diminish 
when  the  boiling  of  the  wax  with  alcohol  had  been  very  long  continued.  It  is 
possible  to  effect  nearly  a complete  separation  of  the  acids  and  the  hydrocarbons  by 
distillation.  It  is  however  not  advisable  to  proceed  in  this  manner,  but  it  is  best 
after  boiling  the  distillate  with  water  to  saponify  the  whole  by  potash.  The  soap  may 
be  removed  by  a syphon  from  the  hydrocarbons  which  float  on  the  surface. 

Palmitic  Acid  from  the  Distillation  of  Myricin. 

The  acid,  having  been  purified  in  the  usual  manner  by  washing  out  the  baryta 
salt  with  ether,  and  the  subsequent  methods  of  purification,  presents  an  appearance 
similar  to  the  acids  obtained  by  saponification.  By  crystallization  the  melting-point 


may  be  raised  to  62°  C. 

CO2.  HO. 

I.  0'2592  grm.  of  this  acid  gave  ....  0'7165  0'293i 

II.  0*250  grm.  of  this  acid  gave  ....  0*6865  0*27925 

III.  0*2776  grm.  of  this  acid  gave  ....  0*75925  0*311 

These  analyses  correspond  in  100  parts  to — 

I.  II.  III. 

Carbon  . . 75*39  74*89  74*61 

Hydrogen  . 12*58  12*40  12*45 

Oxygen  . . 12*03  12*71  12*94 

100*00  100*00  100*00 

The  silver  salt  of  this  acid,  prepared  as  before,  gave  the  following  results  *. — 

I.  0*5006  grm.  of  the  substance  gave 0*1479  silver. 

II.  0*2295  grm.  of  another  preparation  gave  ....  0*0685  silver, 
which  correspond  in  100  parts  to — 

I.  II. 

Silver  . . . . . 29*54  29*84 

CO2.  HO. 

0*3505  grm.  of  the  same  salt  gave  ....  0*6873  0*2758 

which  gives  in  100  parts, — 

Carbon . 53*47 

Hydrogen . . . ...  . 8*74 

Oxygen  and  silver  . . . . 37*79 


100*00 


MR.  BRODIE  ON  MYRICIN. 


99 


These  numbers  prove  the  identity  of  the  acid  from  the  distillation  of  myricin  with 
that  obtained  from  the  saponification  of  that  substance  (p.  283). 

There  are  great  difficulties  in  the  way  of  obtaining  even  a sufficient  quantity  of  this 
acid  for  the  determination  of  its  formula.  To  obtain  even  a very  small  portion  of  it 
of  which  the  purity  may  be  relied  on,  it  is  necessary  to  operate  on  a large  quantity 
of  the  impure  acid  : for  the  preparation  of  this  pure  myricin  is  required,  free  from 
cerotic  acid,  which  it  is  not  easy  to  get  in  any  quantity. 

These  difficulties  have  prevented  me  making  any  further  experiments  with  this 
acid,  the  identity  of  which  however  with  palmitic  acid,  as  obtained  by  Fremy  and 
Stenhouse  from  palm  oil,  and  by  Sthamer  from  Japan  wax,  is  made  out.  I subjoin, 
for  the  sake  of  comparison,  the  silver  determination  of  the  silver  salt  of  the  palmitic 
acid  as  obtained  by  these  chemists. 

Fremy*.  STENHousEf.  SthamerJ. 

Silver,  per  cent.  . . 29‘60  29‘23  29’42  29‘28  29‘51 

This  acid  appears  also  to  be  the  same  as  the  acid  obtained  by  Varrentrapp'^  from 
the  oxidation  of  oleic  acid  by  means  of  lime  and  potash,  which  also  had  the  melting- 
point  of  62°  C.  The  silver  determinations  of  this  acid  gave  as  the  per-centage  of  silver, 

29-27  29-45  29-13, 

numbers  identical  with  my  own. 

Melen. 

It  is  well  known  that  one  of  the  principal  products  of  the  dry  distillation  of  wax 
is  a solid  hydrocarbon.  Ettling,  who  first  analysed  this  substance ||,  concluded  froln 
its  melting-point,  analysis,  and  general  appearance,  that  it  was  identical  with  paraffin, 
a hydrocarbon  then  recently  discovered  by  Reichenbach  in  the  products  of  the  dry 
distillation  of  wood.  The  wax  hydrocarbon  has  therefore  borne  the  name  of  paraffin. 

This  substance  was  supposed,  from  the  analyses  of  Ettling  and  J.  Gay-Lussac, 
to  be  isomeric  with  olefiant  gas. 

Recently,  however,  this  has  been  contested  by  Lewy,  who  analysed  paraffin  from 
various  sources,  and  showed  it,  as  he  conceived,  to  contain  a larger  amount  of  hydro- 
gen than  had  been  previously  supposed.  In  truth  the  average  of  his  analyses  gave, — 

Carbon 85-03 

Hydrogen 14-87 

99-90 

numbers  inconsistent  with  the  old  idea.  The  question  however  is,  whether  M.  Lewy 
experimented  with  a pure  chemical  substance,  for  which  there  is  no  guarantee. 

* Liebig’s  Annalen,  vol.  xxxvi.  p.  45.  Silver  determinations,  V.  VI.  VII. 

t Ibid.  p.  52.  The  mean  of  five  determinations  closely  agreeing.  This  acid  melted  at  60°  C. 

+ Ibid.  vol.  xliii.  p.  342.  The  mean  of  three  determinations. 

§ Ibid.  vol.  XXXV.  p.  209.  1|  Ibid.  vol.  ii.  p.  259. 


100 


MR.  BRODIE  ON  MYRICIN. 


My  own  experiments  confirm  the  analyses  of  Ettling,  and  the  constitution 
originally  assigned  to  the  substance,  to  which  theoretical  considerations  also  lead. 
But  I cannot  see  any  reason  to  believe  the  wax  hydrocarbon  to  be  identical  with  the 
paraffin  of  Reichenbach.  This  name  of  paraffin  has  been  applied  indiscriminately 
to  the  whole  class  of  solid  hydrocarbons,  which  have,  or  have  nearly  the  formula 
H^,  the  identity  of  which  has  been  taken  for  granted,  in  the  absence  of  any  true 
knowledge  as  to  the  chemical  nature  of  the  substances  from  the  decomposition  of 
which  by  heat  they  are  produced.  The  different  melting-points  however  of  these 
substances  point  out  to  us  at  once  a distinction  between  them.  The  paraffin  of 
M.  Lewy  melted  at  46°’8.  A specimen  of  the  paraffin  of  wood  given  to  me  by  Pro- 
fessor Liebig,  and  which  that  gentleman  received  from  Reichenbach,  its  discoverer, 
melted  at  43°’5  C. ; Ettling’s  paraffin  at  57°  to  58°  C.  I confess  it  is  difficult  for  me 
to  conceive  what  substance  in  a state  approaching  to  purity  Lewy  analysed  from  the 
wax  having  the  melting-point  he  has  given,  since  nothing  is  easier  than  to  raise  the 
melting-point  of  the  paraffin  from  the  wax  to  56°  C.,  although  beyond  this  any 
change  is  effected  with  difficulty. 

Cerin  alone  gives  on  distillation  hardly  a trace  of  this  hydrocarbon,  while  it  forms 
a principal  product  of  the  distillation  of  myricin.  The  palmitic  acid  is  separated  by 
saponification,  and  the  general  preparation  of  the  substance  is  the  same  as  in  the 
similar  case  of  the  ceroten  from  Chinese  wax,  to  which  substance  it  is  closely  analo- 
gous. If  the  hydrocarbon  from  the  distillation  of  the  pure  myricin,  the  acids  having 
been  boiled  out  with  potash,  be  pressed  out  in  a press  between  blotting-paper,  it  will 
have  a melting-point  of  about  56°  C.  This  can  be  raised  by  further  crystallization 
out  of  ether  to  60°  C.  The  analysis  of  the  substance  in  this  condition  shows  the 
presence  of  some  body  containing  oxygen,  in  addition  to  the  hydrocarbon. 

CO,.  HO. 

0‘2606  grm.  of  this  substance  gave  ....  0'8094  0*3402 

giving  in  100  parts, — 

Carbon 84*74 

Hydrogen  ....  14*51 

Oxygen  ....  0*75 

10000 

Another  analysis  gave  similar  results.  This  led  me  to  prepare  the  substance  in 
rather  a different  manner.  The  paraffin  having  been  carefully  pressed  out  in  the 
manner  described,  was  rectified  over  potassium,  which  destroys  the  oxygen  com- 
pound. The  distillate  is  perfectly  white  : it  contains  a little  oil,  which  may  again 
be  pressed  out.  By  crystallization  out  of  pure  ether,  the  melting-point  may  now  be 
raised  to  62°  C.  This  substance  was  analysed. 

COa.  HO. 

0*261  grm.  gave  . . . 0*8165  0*3393 


MR.  BRODIE  ON  MYRICIN. 


101 


giving  in  100  parts, — 

Carbon  ....  85-31 

Hydrogen  . . . 14*44 

99-75 

85-71 
14-28 

99-99 

The  difference  between  the  hydrogen  calculated  and  found  is  only  0*16  per  cent., 
which  is  as  near  to  theory  as  such  analyses  can  be  expected  to  come.  Cerotin  melts 
at  81°  C.  The  hydrocarbon  I have  called  ceroten  melts  at  57°  to  58°.  Melissin  melts 
at  85°.  The  wax  hydrocarbon  at  62°  C.,  showing  a precisely  analogous  difference  in 
their  melting-points.  Owing  to  the  numerous  operations  which  are  necessary  before 
this  hydrocarbon  can  be  procured  in  a pure  state,  I have  been  unable  to  make  further 
experiments  with  the  pure  substance.  The  analyses,  however,  the  analogy  of  this 
other  substance  and  the  mode  of  its  formation,  can  leave  no  doubt  but  that  it  is  the 
hydrocarbon  of  the  wax-alcohol  Cgo  Hgo,  to  which  may  be  given  the  name  of  melen. 


The  formula  C„  demands — 

m.  m 

C . 

m 

n 


The  Nature  of  Myricin. 

The  analogy  of  the  products  of  the  decomposition  of  myricin  by  alkalies  and  by  heat, 
to  those  of  the  Chinese  wax  and  of  spermaceti  under  similar  circumstances,  would 
lead  us  to  suspect  that  a similar  relation  exists  between  the  substances  to  which  these 
products  are  due.  If,  however,  we  take  the  numbers  which  have  been  obtained  by 
analysis  for  this  body,  those  for  example  of  Ettling*,  or  those  of  Lewy'|',  and 
attempt  from  these  to  reckon  out  a formula  which  shall  give  a rational  account  of 
these  decompositions,  we  find  a considerable  deficiency  of  carbon.  I give  one 
of  Lewy’s  analyses,  with  which  other  analyses  of  himself  and  other  chemists  are 
sufficiently  accordant;!:. 

Carbon 80*28 

Hydrogen  ....  13*34 

Oxygen 6*38 

100-00 


The  formula  C92  H92  O4,  which  would  account  in  a simple  manner  for  the  decom- 
positions,— 


^32  ^31  ^3 

^60  ^61  O 


C32  ^32  ^4 
^60  Hgo 


^92  H92  O4 


C92  H92  o 


4 


* Liebig’s  Annalen,  ii.  267. 


f Annales  de  Chimie,  xiii.  443. 


t Ibid. 


102 


MR.  BRODIE  ON  MYRICIN. 


requires — 

C92. 

H92 

O4  . 


Atomic  weight- 

81-65 

552 

13-60 

92 

14-75 

32 

100-00 


6/6 


leaving-  a difference  of  one  and  a half  per  cent,  of  carbon,  a difference  too  great  to  be 
attributed  to  any  accidental  error. 

I have  stated  that  the  decompositions  of  the  myricin  are  far  from  being  so  simple 
as  those  of  the  Chinese  wax,  and  that  in  order  to  obtain  either  the  acid  or  the  wax 
alcohol,  long  and  repeated  crystallizations  are  necessary.  This  at  once  led  me  to  the 
suspicion  that  the  so-called  myricin  was  no  pure  chemical  substance,  but  a mixture 
of  two  or  more  bodies.  Subsequent  experiment  confirmed  this  view. 

The  residue  of  the  wax,  after  the  cerotic  acid  has  been  boiled  out  by  alcohol, 
melts  at  64°  C.  It  is  but  very  slightly  soluble  in  alcohol.  Pure  ether,  however,  will 
dissolve  it  without  much  difficulty.  It  crystallizes  out  of  this  reagent  in  light  feathery 
crystals.  The  precipitate  and  the  residue  from  the  solution,  evaporated  to  dryness, 
have  different  melting-points.  I succeeded  in  this  manner  in  raising  the  melting- 
point  of  the  precipitate  to  71°‘5.  This  end  may  be  more  readily  obtained  by  adding 
a small  quantity  of  naphtha  to  the  ether. 

The  following  analyses  were  made  of  a substance  of  72°,  which  after  repeated  cry- 
stallizations was  precipitated  on  the  filter  out  of  the  hot  solution,  the  filter  being 
kept  hot  by  means  of  a hot  water  apparatus.  I have  not  succeeded  in  raising  the 
melting-point  beyond  72°.  The  substance  is  now  highly  crystalline  in  appearance, 
which  the  impure  myricin  is  not,  and  of  about  the  consistency  of  wax.  I regard  it  in 
this  state  as  pure. 


CO,. 

HO. 

I*.  0-2592  grin,  of  substance 

gave  . . 

. . 0-7735 

0-3135 

II.  0-2243  grm.  of  substance 

gave  . . 

. . 0-672 

0-269 

which  give  in  100  parts, — 

I. 

II. 

Carbon  . . . 

81-38 

81-70 

Hydrogen  . . . 

13-44 

13-33 

Oxygen  . . . 

5-18 

4-97 

100-00 

100-00 

These  numbers  are  very  different  from  any  which  have  been  before  obtained  for 
any  substance  from  the  myricin,  and  different  from  those  which  I myself  have  ob- 


* The  thorough  combustion  of  these  waxes  is  difficult,  and  I have  made  many  experiments  to  ascertain  the 
best  method  of  analysis.  Bichromate  of  lead  was  the  material  generally  employed.  But  when  the  combustion 
is  made  very  slowly,  I believe  it  to  be  complete  even  with  oxide  of  copper  alone.  The  greater  number  of  such 
analyses  in  this  investigation  were  made  by  my  chemical  assistant,  Mr.  L.  Hoffmann,  to  whose  care  and  skill 
I am  much  indebted. 


MR.  BRODIE  ON  MYRICIN. 


i03 


tained  for  substances  of  a lower  melting-point.  The  crystalline  appearance  marks 
the  purity  of  the  substance,  and  notwithstanding  the  slight  difference  in  the  hydro- 
gen, I cannot  but  regard  it  as  the  body  C92  H92  O4,  with  the  calculated  formula  of 
which,  as  given  above,  it  sufficiently  agrees.  I must  add  that  the  substance  is  separable 
with  extreme  difficulty.  The  next  precipitate  from  the  solution  from  which  the  above 
substance  had  been  separated,  had  a melting-point  half  a degree  lower,  and  gave  to 
analysis  rather  less  carbon,  namely,  C.  8 TO  per  cent. 


The  greater  part  of  the  difficultly  saponifiable  portion  of  the  wax  appears  to  consist 
of  the  substance  the  analysis  of  which  I have  just  given,  and  to  which  we  may  confine 
the  name  myricin.  We  have,  however,  clearly  some  other  body  present  accompany- 
ing it,  the  products  of  the  decomposition  of  which  by  potash  are  to  be  found  with 
both  the  acid  and  the  wax-alcohol  procured  by  saponification  of  the  impure  substance, 
which,  as  I have  said,  render  extremely  difficult  the  preparation  of  these  bodies  in  a 
pure  state,  i shall  proceed  to  give  some  experiments  which  throw  some  true  light 
upon  the  nature  of  this  substance,  although  I cannot  say  that  its  history  is  satisfac- 
torily made  out.  The  solution  of  ether  or  naphtha  (p.  2/8)  from  which  the  melissin 
of  85°  has  been  separated,  still  contains  a large  quantity  of  substance  of  a similar  ap- 
pearance, but  of  a melting-point  much  lower  than  that  of  the  melissin  itself.  Notwith- 
standing however  the  differences  in  the  melting-point,  analysis  shows  us  but  little  or 
rather  no  difference  in  the  constitution  of  the  different  portions  of  this  substance. 
In  the  case  for  example  of  a substance  melting  at  78°'5  C., — 


CO2.  HO. 

0’2522  grm.  gave  ....  0’764  0‘324 

which  gives  in  100  parts, — 


Carbon  . . 

. . . 82-59 

Hydrogen  . 

. . . 14-27 

Oxygen . . 

. . . 3-14 

100-00 

In  the  case  again  of  a substance  melting  at  72°, — 

CO,. 

HO. 

0-249  grm.  gave  . . . 

. 0-75075 

0-317 

which  gives  in  100  parts, — 

Carbon  . . 

. . . 82-22 

Hydrogen  . 

. . . 14-14 

Oxygen 

. . . 3-64 

Other  analyses  gave  similar  results. 


100-00 


104 


MR.  BRODIE  ON  MYRICIN. 


These  analyses  do  not  differ  seriously  from  one  another,  and  give  precisely  the 
numbers  of  the  melissin  itself  (p.  279).  The  numbers  however  are  consistent  with 
various  formulae  besides  that  of  the  melissin.  At  72°  the  melting-point  is  extremely 
constant.  A portion  of  substance  was  obtained  at  this  melting-point  by  repeatedly 
filtering  the  etherial  solution  from  the  melissin  which  first  crystallized  out  of  the  hot 
liquid.  A time  arrived  when  there  was  no  difference  between  the  melting-point  of 
the  portion  which  first  crystallized  out  of  the  hot  solution  and  which  was  on  the 
filter,  and  that  which  afterwards  crystallized  out  of  the  fluid  which  had  passed 
through.  The  melting-point  in  both  cases  was  72°.  By  heating  with  lime  and  potash, 
as  in  the  case  of  melissin,  this  substance  of  72°  also  affords  an  acid,  which  after  the 
usual  preparation,  gives  very  different  numbers  to  those  of  the  melissic  acid.  This 


acid  melts  at  77°'5. 

COg.  HO. 

I.  0*256  grm.  gave 0*735  0*3015 

II.  0*267  grm.  gave  . - . . . . 0*765  0*311 

III.  0*2551  grm.  gave 0*730  0*2995 

giving  in  100  parts, — 

I.  II.  III. 

Carbon  ....  78*28  78*14  78*05 

Hydrogen  . . . 13*09  12*94  13*05 

Oxygen  ....  8*63  8*92  8*90 

100*00  100*00  100*00 


Between  the  second  and  third  analyses  the  substance  was  twice  crystallized  out  of 
ether.  The  substance  dissolved  by  the  ether  had  the  same  melting-point  of  78°  as 
the  substance  on  the  filter. 


The  silver  salt  of  this  acid  gave  the  following 

numbers  : — 

I.  0*5054  grm.  of  substance  gave  . . 

CO^.  HO. 

. 1*127  0*4572 

II.  0*5182  grm.  of  substance  gave  . . 

. 1*1505  0*467 

giving  in  100  parts, — 

I. 

II. 

Carbon 60*80 

60*56 

Hydrogen  ....  10*05 

10*01 

Oxygen  and  silver  . 29*15 

29*43 

100*00 

100*00 

I.  0*617  grm.  gave  on  ignition 

. . . 0*1375  silver. 

II.  0*7315  grm.  gave  on  ignition 

. . . 0*1625  silver. 

giving  per  cent. — 

I. 

II. 

Silver  ....  22*28 

22*21 

Mil.  BRODIE  ON  MYRICIN. 


105 


These  analyses  perfectly  agree  with  the  formiilse  for  the  acid,  C49  H49  O4. 


Calculated. 


78-4 

13-0 

8-6 


100-0 


Calculated. 


60-9 

9-9 

6-8 

22-4 


100-0 


If  we  compare  the  numbers  of  this  acid  with  those  of  the  substance  from  the 
oxidation  of  which  it  was  derived,  we  shall  see  that  it  is  impossible  to  account  for 
the  changes  in  the  same  simple  manner  as  in  other  cases  of  such  transformation.  It 
would  not  be  difficult  to  reckon  out  a formula  that  without  great  violence  should 
account  for  it,  but  it  is  hardly  worth  while  to  do  so,  since  notwithstanding  the  per- 
fect agreement  of  the  calculated  and  theoretical  numbers,  it  is  impossible  to  assert 
with  certainty  that  either  it  or  the  body  from  which  it  is  derived  are  pure  chemical 
substances.  There  is  too  great  a difficulty  in  the  perfect  separation  of  the  melissin 
to  lead  us  to  hope  that  it  can  absolutely  be  removed  by  the  method  I have  given. 
I failed  in  attempting  to  procure  in  larger  quantities  this  substance  of  72°.  The 
melting-point  was  very  constant  at  but  on  oxidizing  a considerable  quantity  of 
this  substance  with  lime  and  potash,  acids  were  procured,  which  by  crystallization 
were  separable  in  the  same  manner  as  the  substance  from  which  they  were  derived, 
and  the  purification  and  perfect  separation  of  which  presented  the  same  difficulties. 
I obtained  in  this  way  an  acid  having  nearly  the  melting-point  of  85°,  the  melting- 
point  of  melissic  acid,  and  also  an  acid  with  a lower  melting-point  than  77°,  but  of 
which  the  melting-point  was  not  so  absolutely  constant  as  to  induce  me  to  investigate 
it  further.  I give  however  these  analyses,  since  they  unquestionably  prove  the  exist- 
ence of  some  other  body  in  addition  to  the  melissin,  in  the  products  of  the  saponifi- 
cation of  wax,  which  by  oxidation  is  capable  of  passing  into  an  acid  belonging  to  the 
series  O4.  Since  it  is  only  a pure  body  or  a mixture  of  acids  of  this  series 

which  could  give  rise  to  the  results  I have  given,  and  from  the  great  difficulty  of 
separation,  the  acid  in  all  probability  contains  a very  large  number  of  equivalents  of 
carbon,  whether  it  have  precisely  the  formula  I have  above  given  or  not. 

Mixed  with  the  palmitic  acid  of  62°,  is  found  another  acid  of  a much  lower  melt- 
ing-point, and  which  presents  similar  difficulties  of  separation  from  the  palmitic  acid 
to  those  of  the  substance  mixed  with  the  melissin  from  the  melissin  itself.  This  acid 
is  very  soluble  in  alcohol,  unctuous  to  the  touch,  and  of  a very  low  melting-point. 
I do  not,  however,  mean  to  assert  that  the  other  wax-alcohol  exists  in  the  wax  in 

MDCCCXLIX.  p 


106 


MR.  BRODIE  ON  MYRICIN. 


combination  with  this  unctuous  acid,  the  presence  of  which  is  very  probably  due  to 
another  source. 

This  alcohol  may  possibly,  as  well  as  the  melissin,  be  combined  with  palmitic  acid, 
or  it  may  be  in  some  altogether  different  form  in  the  wax.  Even  after  long  boiling 
with  alcohol,  the  myricin  has  a slight  wax  smell,  and  it  is  possible  that  this  unctuous 
acid  is  the  product  of  the  action  of  potash  upon  the  oil  which  is  one  of  the  con- 
stituents of  the  wax,  and  from  which  I have  in  fact  procured  an  acid  of  this  nature. 
This  oil,  or  rather  grease,  which  was  analysed  by  Lewv,  is  a very  curious  substance. 
The  other  constituents  of  the  wax  are,  in  a pure  state,  inodorous  and  crystalline, 
and  to  it  the  wax  owes  its  tenacity  and  peculiar  smell.  I have  made  some  experi- 
ments as  to  its  nature,  and  procured  from  it  also  an  acid  and  an  unsaponifiable 
substance ; I will  not,  however,  here  enter  upon  the  matter,  hoping  at  some  future 
time  to  resume  its  investigation. 

I must  not  omit  to  mention,  with  reference  to  the  bees’-wax  from  Ceylon,  of  which 
I spoke  in  a former  paper,  and  which  contained  no  cerotic  acid,  that  it  possesses  all 
the  general  characters  of  the  other  portion  of  the  wax.  Like  the  impure  myricin,  it 
contains  more  than  one  substance.  The  wax  itself  has  a melting-point  of  65°'5. 
When  digested  with  ether  in  the  cold,  a portion  is  taken  up  by  the  ether,  and  a residue 
left  of  the  melting-point  of  67° ; and,  when  dissolved  in  ether,  if  the  etherial  solution 
be  filtered  while  warm  from  the  first  portions  of  the  precipitate  which  crystallizes 
out,  a substance  may  be  obtained,  of  the  melting-point  of  72°,  crystalline  in  appear- 
ance, hardly  at  all  acted  on  by  a solution  of  potash,  but  readily  saponified  by  melted 
potash ; resembling  in  short  in  all  its  properties  the  pure  myricin.  The  products  of 
the  saponification  of  the  wax  itself  closely  resemble  those  of  the  impure  myricin,  and 
present  similar  difficulties  of  separation. 

An  acid  may  be  obtained  from  it  having  the  character  of  palmitic  acid,  and  I have 
also  procured  from  this  wax  the  substance  melissin,  having  a melting-point  of  84°. 
The  analysis  VI.  p.  279,  was  made  from  a preparation  from  Ceylon  wax. 


I will  sum  up  the  results  of  this  investigation  by  giving  a list  of  the  principal  sub- 
stances of  which  an  account  has  been  given  in  this  and  the  preceding  papers.  This 
table  will  exhibit,  at  one  view,  their  relations  to  one  another,  and  to  the  natural 
substances  from  the  decomposition  of  which  they  are  derived. 

Cerotic  acid  [cerin] =^54  H54  O4. 


Chlor-cerotic  acid 

Cerotic  ether 


— C54 

=C58H 


1^42  O4. 

ICk  ^ 


'12 

58  04“ 


^54  H53  O3. 

H5  O. 


=c 


58 


fH 

.Cl 


46 


o 


C4 

J 


O3. 


12 


H 

IC4  H5  O 


12 


Chlor-cerotic  ether  . . 


MR.  BRODIE  ON  MYRICIN. 


Cerotin 

Sulphate  of  oxide  of  cerotyle  . . 

Chlor-cerotal 


107 


Ceroten  [parafiin] 


Chlor-ceroten 


Chinese  wax 


— C54  H56  O2. 

= SO„C,,  H55O+HO. 


rH4i  Q 


*13 


H 


54  •**■54* 


^54 


fH. 


Cl 


35* 


19* 


— <f  r /^33- 

I Hoo. 


•"54 


*32* 

Cl22* 


— ^108  ^108  — 


1^54  H53  O3. 

^^54  H55 


Melissin — CgoH02O2- 

Chlor-melal Og. 

^^n4-5 

Melissic  acid =^00  Hgo  O4. 

Melen  [paraffin] =Cgo  Hgg. 

Palmitic  acid — C32  H32  O4. 

Myricin  (pure) =C92  H92  04=|p^^  O^’ 

^'^60  -*^61 

I might  add  to  this  list  the  acid  C49  H49  O4,  the  constitution  of  which  however,  for 
the  reasons  I have  given,  I cannot  consider  to  be  made  out  with  sufficient  certainty. 

We  should  naturally  suspect  some  intimate  chemical  relation  between  wax  and  fat 
from  their  similar  appearance  and  properties.  This  suspicion  gave  rise  to  the  idea 
that  wax  was  convertible  into  fat,  and  to  the  hypothesis  that  wax  was  to  be  regarded 
as  the  aldehyde  of  stearic  acid,  and  was  capable  of  passing  into  that  substance  by  a 
simple  process  of  oxidation,  a view  of  its  chemical  nature  entirely  without  foundation. 
From  the  preceding  inquiry,  we  arrive  however  at  the  knowledge  of  a no  less  remark- 
able relation  between  these  substances. 

Margaric  acid  was  recently  the  last  of  that  singular  series  of  acids  of  the  type 
H^04,  which  commencing  with  formic  acid  comprehended  acetic  acid,  the  volatile 
acids  of  butter  and  the  acid  of  spermaceti,  and  sethal  was  the  last  of  the  corresponding 
alcohols.  In  the  wax  acids  and  alcohols  of  which  an  account  has  been  given  in  this 
and  the  preceding  papers,  we  have  bodies  at  the  other  extremity  of  the  series  stand- 
ing in  a similar  relation  to  margaric  acid  and  to  sethal,  as  that  in  which  acetic 
and  butyric  acid,  and  alcohol  and  potatoe  oil  stand  to  them  at  the  commencement. 

p 2 


108 


MR.  BRODIE  ON  MYRICIN. 


An  intervening  acid  of  the  series,  the  acid  C44  H44  O4,  has  lately  been  discovered  by 
VoLCKER*  in  the  oil  of  the  Guilandina  Moringa,  and  the  investigation  of  the  nume- 
rous class  of  vegetable  oils  and  waxes  will  doubtless  afford  other  bodies  of  the  group. 

Notwithstanding  the  many  different  properties  of  these  substances,  we  find  their 
chemical  analogies  constant,  and  the  mutual  relation  of  the  acid,  the  alcohol  and  the 
hydrocarbon,  is  the  same  between  bodies  containing  sixty  as  between  those  contain- 
ing only  four  equivalents  of  carbon.  Through  at  least  half  the  series,  from  thirty  to 
sixty  equivalents,  the  same  physical  type  of  fat  prevails.  As  a fat  is  doubtless  but  a 
soft  kind  of  wax,  so  may  not  alcohol  be  but  a very  fluid  form  of  fat  ? Alcohol  has  not 
yet  been  solidified,  but  one  cannot  help  suspecting  that  when  solidified  it  will  appear 
as  a wax  or  fat. 

Direct  experiment  has  shown  us  that  in  the  body  of  the  bee  sugar  is  converted 
into  wax.  A simple  analysis  of  the  two  substances  showed  that  the  carbon  and 
hydrogen  were  in  the  same  ratio  in  both,  and  that  the  change  could  be  effected  by  a 
simple  deoxidation  of  the  sugar.  Of* the  way  in  which  this  change  is  effected  we  are 
ignorant.  The  true  formula  of  these  wax  substances  however  shows  that  they  belong 
to  the  very  type  of  bodies  which  are  the  ordinary  products  of  fermentation,  and  are 
connected  with  them  by  the  strongest  chemical  analogies.  A new  mode  of  fermenta- 
tion produced  butyric  acid  out  of  sugar ; might  not  another  kind  of  fermentation 
produce  wax  r 

Until  we  know  the  nature  of  the  whole  of  the  ingredients  of  the  wax,  it  is  useless 
to  speculate  on  the  law  of  such  a change.  Although  the  wax  itself  is  no  pure 
chemical  substance,  but  a mixture  of  substances  differing  nearly  three  per  cent,  from 
one  another  in  their  amount  of  carbon,  yet  the  analysis  of  the  whole  bees’-wax  gives 
results  showing  in  different  specimens  which  I have  examined,  no  difference  of  eon- 
stitution  which  analysis  can  reach.  This  renders  it  probable  that  the  action  is  definite, 
and  that  the  sugar  in  all  cases  loses  the  same  amount  of  oxygen,  although  the 
remaining  elements  may  in  different  cases  be  differently  grouped. 

* Liebig’s  Annalen,  vol.  Ixiv.  p.  342. 


[ 109  ] 


IX.  On  the  Structure  and  Development  of  the  Liver.  By  C.  H.  Jones,  M.D. 
Communicated  hy  Sir  Benjamin  Collins  Brodie,  Bart.,  F.R.S. 


Received  June  16, — Read  June  17,  1847. 

In  venturing  to  offer  a second  communication  to  the  Royal  Society  respecting  the 
structure  of  the  liver,  I feel  the  rather  anxious  to  do  so,  that  I may  have  an  oppor- 
tunity of  correcting  an  error  and  supplying  a deficiency  which  existed  in  my  previous 
paper.  In  the  following  observations  I purpose  to  present  some  account  of  the 
structure  of  the  liver  examined  in  the  ascending  series  of  animals,  and  also  to  de- 
scribe the  several  stages  of  its  evolution  in  the  embryo ; in  this  way  I trust  I may 
be  able  to  exhibit  the  characteristic  structural  features  of  the  organ  as  it  exists  in  Man 
and  the  higher  animals,  and  also  to  determine  the  true  place  which  ought  to  be 
assigned  to  it  in  a classification  of  the  various  glandular  organs  occurring  in  the 
same. 

I am  not  aware  that  any  detailed  account  of  the  structure  of  the  liver  has  been 
recently  published,  except  that  by  M.  Natalis  Guillot,  which  however,  so  far  as  I 
comprehend  it,  does  not  seem  to  be  one  that  can  be  readily  accepted ; the  idea  that 
the  minute  biliary  ducts  and  lymphatics  originate  together  in  a common  net-work, 
is  d priori  improbable,  and  entirely  opposed  to  conclusive  evidence  (as  I think), 
which  will  be  subsequently  adduced.  A very  interesting  paper  on  the  structure  and 
function  of  the  liver  has  also  appeared  in  the  4th  volume  of  the  Guy’s  Hospital 
Reports,  from  the  pen  of  Dr.  Williams  ; to  his  labours  I shall  several  times  have 
occasion  to  refer,  but  it  will  be  seen  that  I differ  from  him  in  several  particulars, 
especially  respecting  the  importance  of  the  basement  or  limitary  membrane. 

Commencing  with  the  Bryozoon  polype  as  the  lowest  individual  in  the  animal 
series  in  which  distinct  traces  of  a liver  have  been  discovered,  we  find  that  (according 
to  Dr.  Farre  and  Professor  Owen)  there  are  a number  of  follicles  filled  with  a rich 
brown  secretion,  which  open  into  a distinct  compartment  of  the  stomach  ; these 
doubtless  constitute  an  hepatic  organ. 

In  the  Asterias,  where  though  the  several  systems  of  organs  are  sketched  out,  they 
yet  remain  without  any  appearance  of  concentration  and  high  individual  develop- 
ment, there  exists  considerable  doubt  as  to  the  part  of  the  digestive  system  to  which 
the  function  of  a liver  is  to  be  attributed ; the  most  usual  opinion  seems  to  regard 
the  ramified  appendage  found  at  the  dorsal  aspect  of  the  stomach  as  having  this 
character.  Dr.  Williams,  however,  considers  it  more  probable  that  the  layer  of  cells,' 
lining  the  dilated  cseca  of  the  prolongations  of  the  digestive  sac  into  the  rays,  discharges 


110 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


the  office  of  an  hepatic  apparatus,  grounding  his  opinion  on  a comparison  of  the 
secreting  elements  in  the  two  organs.  My  own  examination  of  the  dorsal  appendage 
of  the  stomach  does  not  lead  me  to  agree  with  Dr.  Williams,  in  excluding  it  from 
participating  in  the  function  of  a liver;  I find  it  to  consist  of  csecal  follicles  which 
present  occasional  bulgings ; the  diameter  of  these  is  about  ^^th  of  an  inch  ; they 
lie  packed  together  in  groups  which  are  easily  visible  to  the  naked  eye : in  structure 
they  consist  of  an  homogeneous  membrane,  which  encloses  a mass  of  nuclear  granules 
varying  in  size  from  9 --4^0  Q-oth  of  an  inch  ; also  granular  globules,  oval  or  circular 
transparent  vesicles,  yellow  amorphous  matter  and  oil-drops ; between  these  and 
the  contents  of  the  gastric  caeca  I did  not  observe  any  remarkable  difference ; never- 
theless, I do  not  mean  to  imply  that  the  dorsal  appendage  serves,  like  the  gastric 
caeca,  for  the  reception  of  the  chyle  ; but  only  that,  admitting  the  secretory  apparatus 
of  the  latter  may  possibly  perform  the  office  of  producing  bile,  there  seems  no  suffi- 
cient ground,  from  difference  of  structure,  for  supposing  the  former  to  be  destined  to 
a different  purpose.  I ought,  however,  to  mention  that  in  one  or  two  specimens  I 
examined,  the  structure  of  the  appendage  in  question  corresponded  more  nearly  to 
the  account  given  of  it  by  Dr.  Williams,  but  this  appeared  to  me  to  be  a deviation 
from  the  natural  condition ; nor  indeed  have  I ever  observed  anything  which  could 
lead  me  to  assent  to  the  opinion  that  it  represents  a pancreas,  an  organ  which  first 
manifests  itself  unequivocally  in  the  class  of  Fishes,  and  exhibits  in  the  different  genera 
so  many  beautiful  stages  of  progressive  complication. 

In  the  Echinidm,  another  kindred  family,  we  find  the  alimentary  canal,  apparently 
of  great  simplicity,  passing  from  the  wonderful  dental  apparatus  on  one  side,  to  the 
opposite  pole  of  its  elaborately  constructed  shell,  performing  only  a few  gyrations  in 
its  course;  a few  salivary  caeca  are  described  as  entering  the  canal  just  before  the 
oesophagus  commences,  but  no  mention  is  made  of  any  structure  serving  the  purpose 
of  a liver  ; I have,  however,  found  in  the  delicate  walls  of  the  intestine  a layer  of 
elongated  follicles,  much  resembling  the  gastric  tubuli  of  higher  animals  ; these 
occupy  the  whole  thickness  of  the  intestinal  wall,  and  are  closely  in  apposition  with 
each  other;  their  colour  is  a deep  yellow;  they  consist  of  nuclear  granules  and 
amorphous  matter,  with  probably  a yellow  fluid ; these  materials  seem  to  cohere 
simply  together,  and  not  to  be  contained  in  tubes  of  homogeneous  membrane ; the 
diameter  of  the  follicle-shaped  masses  measures  about  of  an  inch.  If  I be  cor- 

rect in  supposing  these  follicles  to  secrete  a fluid  analogous  to  bile,  it  would  give 
additional  probability  to  the  opinion  of  Dr.  Williams  respecting  the  function  of  the 
gastric  caeca  of  the  Asterias. 

In  the  class  of  Annelides  we  may  expect  to  find  the  hepatic  apparatus  in  a very 
simple  and  primitive  form,  corresponding  to  the  general  configuration,  which  exhibits 
in  so  marked  a manner  the  law  of  irrelative  repetition.  I shall  describe  the  minute 
structure  of  the  hepatic  gland  in  three  different  instances,  where  its  existence  and 
position  are  satisfactorilyascertained,  viz.  in  the  Earthworm  {Lumhricus  terrestris),  the 


AND  DEVELOPMENT  OF  THE  LIVER. 


in 


Leech  {Hirudo  medicinalis),  and  the  Sandworm  {Arenicola  Phcatorvm)  : among  these 
we  shall  find  some  instructive  and  remarkable  differences,  the  existence  of  which 
seems  to  indicate  clearly  that  we  must  not  rely  too  much  on  finding  exact  analogy  of 
structure  in  any  organ,  even  in  the  individuals  of  the  same  class.  In  the  Earthworm, 
a thin  yellow  stratum  is  found  applied  over  a great  part  of  the  outer  surface  of  the 
intestine ; it  adheres  intimately  to  it,  and  seems  to  be  moulded  on  the  convexities  of 
the  sacculi,  not  dipping  deeply  into  the  furrows  by  which  they  are  separated.  I have 
already  described  this  yellow  layer  as  consisting  of  dark-yellow  masses,  the  majority 
of  which  cannot  be  seen  to  have  an  enveloping  cell-membrane,  while  in  others  it  is 
clearly  perceptible  though  of  extreme  tenuity ; the  masses,  with  or  without  this  en- 
velope, are  often  seen  elongated  into  a conical  form,  the  apex  directed  towards  the 
intestine,  to  which  it  often  adheres  pretty  firmly;  from  this  circumstance  I formerly 
conceived  that  the  biliary  secretion  was  discharged  by  the  bursting  of  the  cells  into  the 
cavity  of  the  intestine,  each  cell  representing  for  a short  space  an  attached  follicle,  and 
it  is  not  impossible  that  this  may  be  the  case  to  some  extent.  But  there  is  another  mode 
in  which  the  bile  may  come  to  exert  its  action  on  the  chyle  (if  such  indeed  be  necessary), 
viz,  by  the  latter  percolating  the  coats  of  the  intestine,  and  consequently  the  layer  of 
hepatic  substance,  before  it  is  absorbed  by  the  ramifications  of  the  deep  abdomino- 
dorsal vessel.  This  latter  opinion  seems  to  be  strongly  supported  by  the  unques- 
tionable condition  of  another  part  of  the  intestinal  apparatus,  known  by  the  name  of 
Typhlosole : this  blind  tube,  which  is  beautifully  plicated  on  its  surface,  extends  along 
the  dorsal  aspect  of  the  intestine  from  the  gizzard  nearly  as  far  as  the  vent.  In  struc- 
ture it  consists  of  a strong  homogeneous  membrane,  covered  by  a layer  of  ciliary 
epithelium,  continuous  with  that  which  may  be  often  seen  on  the  rest  of  the  intestinal 
surface,  while  internally  it  is  lined  by  a thick  stratum  of  biliary  cells,  almost  precisely 
similar  to  those  on  the  exterior  of  the  intestine,  and  forming  with  them  one  con- 
tinuous system.  Now  the  typhlosole  thus  seems  to  be  an  inflection  of  the  intestinal 
wall  for  the  purpose  of  straining  off  the  chyle  from  the  coarse  mass  of  the  ingesta; 
and  as  it  is  certain  that  the  biliary  matter  is  not  discharged  from  the  cells  which  line 
it  into  the  cavity  of  the  intestine,  it  seems  also  probable,  that  at  other  parts  of  the 
intestinal  surface  the  process  is  the  same,  the  chyle  transuding  through  them  as  it 
does  through  the  membrane  of  the  typhlosole. 

In  the  Leech,  as  Prof.  Owen  has  described  it,  the  hepatic  apparatus  appears  as  a 
brown  tissue,  extending  along  the  alimentary  canal  between  the  nervous  cords  and 
the  mucous  glands,  and  also  upon  the  dorsal  aspect  of  the  anterior  part  of  the  cavity. 
It  is  composed,  he  states,  of  a congeries  of  elongated,  convoluted  and  irregularly  con- 
stricted follicles,  which  are  united  in  groups  by  the  confluence  of  their  ducts  into  a single 
slender  excretory  tube : that  this  tissue,  so  well  described,  is  truly  the  hepatic  organ, 
cannot  for  a moment  be  doubted  by  any  who  have  examined  it  with  the  microscope, 
the  follicles  being  filled  with  minute  spherules  of  a deep  yellow  colour,  resembling 
precisely  those  whieh  crowd  the  biliary  cells  in  the  Earthworm.  Regarding  it  then 


112 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


as  the  hornologue  of  the  hepatic  apparatus  we  have  just  examined,  I will  enter  on  a 
rather  more  particular  account  of  it,  which  will  disclose  I think  some  characters 
illustrative  of  hepatic  structure  in  general.  It  may  be  described  as  consisting  of  two 
portions,  one  in  which  the  constituent  cells  are  free,  entirely  separate  from  each  other, 
or  only  fused  together  in  very  small  groups,  and  another  in  which  the  cells  are  com- 
pletely fused  together  so  as  to  represent  either  simple  undilated  tubes,  or  tubes  irre- 
gularly constricted  and  bulged  at  intervals  ; the  former  is  evidently  that  part  of  the 
organ  where  the  production  of  fresh  cells  takes  place ; these  are  seen  at  first  as 
granular  cells  with  envelopes  more  or  less  distinct,  but  having  only  imperfect  traces  of 
nuclei ; subsequently  the  characteristic  biliary  spherules  appear  in  them,  and  at  last 
fill  them  completely.  Now  the  cells  becoming  developed  in  this  manner  (and  they 
proceed  exactly  in  a similar  manner  in  the  Earthworm)  may  either  become  fused 
together  to  constitute  the  tubes  above  described,  or  they  may  lose  all  trace  of  an  en- 
veloping membrane  ; their  component  spherules  separating  from  each  other,  and  the 
cell  at  last  undergoing  complete  disintegration  on  the  spot  where  it  had  been  originally 
formed,  while  its  elaborated  contents  are  probably  absorbed  into  the  circulating 
stream,  from  whence  as  plasma  they  had  proceeded.  The  contents  of  the  tubes  are 
doubtless  poured  into  the  intestine,  while  the  debris  of  the  free  parenchymal  cells 
are  scattered  throughout  the  surrounding  tissue,  and  thus  in  this  low  Annelide  we 
seem  to  recognise  a division  of  the  hepatic  apparatus  into  two  portions,  similar  to 
those  which  we  shall  shortly  distinguish  in  the  higher  animals  ; these  have  probably 
separate  functions,  the  tubular  influencing  by  its  secretion  the  intestine  and  its  con- 
tents, while  the  parenchymal  seems  adapted  to  supply  material  directly  for  the  use 
of  the  respiratory  process. 

In  the  Arenicola,  the  biliary  cells  are  of  a lighter  colour  than  in  the  Leech  or 
Earthworm  ; they  are  at  first  of  a pale  granular  aspect  and  often  exhibit  nuclei ; 
subsequently  they  acquire  dark  oily-looking  contents,  and  often  change  their  form, 
becoming  remarkably  elongated  ; their  diameter  varies  from  y-Q^o  q to  g^th  of  an  inch. 
If  the  outer  surface  of  the  intestine  be  examined  with  a low  power,  it  is  found  to 
present  the  convexities  of  numerous  short  sacculi  with  intervening  furrows,  and  to 
be  perfectly  even  and  defined,  while  the  inner  surface,  on  the  contrary,  has  a floccu- 
lent,  almost  ragged  appearance.  This  effect  is  due  to  the  disposition  of  the  cells, 
which  form  a moderately  thick  stratum,  resting  on  an  homogeneous  membrane,  the 
sole  constituent  of  the  intestinal  wall ; the  cells  are  therefore  actually  in  the  cavity 
of  the  intestine,  and  in  immediate  contact  with  its  contents  ; they  contrast  herein 
remarkably  with  those  of  the  Earthworm,  which  we  have  seen  to  lie  on  the  outside, 
for  the  cells  of  the  Sandworm  may  be  completely  removed  by  washing  the  inner 
surface  of  the  intestine,  while  those  of  the  Earthworm  can  be  thus  detached  only 
from  the  exterior. 

These  three  instances  from  among  the  Annelides  seem  to  exhibit  the  extreme  varieties 
of  condition  which  the  hepatic  apparatus  is  capable  of  assuming.  In  the  Earthworm 


AND  DEVELOPxMENT  OF  THE  LIVER. 


113 


it  is  wholly  parenchymal,  in  the  Sandworm  wholly  included  by  the  intestinal  mem- 
brane, while  in  the  Leech  it  is  of  a mixed  kind,  consisting  partly  of  tubes  continuous 
with  the  intestine  and  partly  of  free  parenchymal  cells. 

In  the  class  of  Insects,  however  widely  the  external  form  and  the  organs  of  the 
animal  functions  may  vary,  the  hepatic  apparatus  preserves  a remarkable  uniformity, 
consisting'  of  long  slender  cylindrical  tubes  varying  in  number  from  4 to  200. 
Besides  these  tubes  however,  of  whose  truly  hepatic  character  but  little  if  any  doubt 
can  I think  exist,  there  is  another  structure  whose  function  is  more  doubtful;  this  is 
the  so-called  adipose  tissue,  which  Mr.  Newport  believes  to  serve  as  a reservoir  of 
nutriment,  and  also  to  fulfill  in  some  way  the  office  of  lymphatic  vessels,  while  Bur- 
MEiSTER,  Oken  and  Treviranus  agree  in  regarding  it  as  a portion  of  the  hepatic 
apparatus.  The  opinion  of  these  latter  authorities  is  that  to  which  I incline,  for 
reasons  which  I will  state,  when  I have  given  a description  of  the  structure  of  the 
two  systems  of  organs  now  adverted  to.  The  hepatic  tubes  in  the  Blow-fly  {Musca 
vomitoria)  for  a considerable  part  of  their  course  present  remarkable  dilatations  and 
constrictions  ; these  are  sometimes  situated  so  as  to  face  each  other  on  opposite 
sides  of  the  tube,  at  other  parts  they  are  placed  more  nearly  alternate.  Towards  its 
commencement  each  tube  is  found  to  consist  of  a number  of  vesicles,  which  are 
arranged  in  a series  so  as  to  overlap  each  other;  these  vesicles  are  more  or  less 
perfectly  fused  together,  their  coalescence  becoming  more  complete,  and  the  margin 
more  even  as  we  advance  towards  the  intestinal  extremity  of  the  tube.  In  many 
insects  the  walls  of  the  tubes  are  perfectly  even  and  present  no  bulgings  or  constric- 
tions ; even  the  terminal  blind  extremity  is,  I think,  for  the  most  part  undilated.  A 
most  distinct  and  strongly-marked  basement  membrane,  unsupported  by  any  fibrous 
tissue,  but  often  covered  by  minute  ramifications  of  tracheae,  constitute  the  wall  of 
the  tubes ; it  is  perfectly  homogeneous,  but  presents  nothing  that  I have  ever  seen 
corresponding  to  the  germinal  centres  of  Mr.  Goodsir.  On  the  interior  of  the  base- 
ment membrane  is  a layer  of  granular  matter  of  variable  thickness  ; this  is  often  of 
a deep  yellow  tint  from  the  presence  of  biliary  matter,  or  rendered  opake  for  a 
greater  or  less  extent  by  deposits  of  oily  matter  ; in  it  are  imbedded  cells  which  are 
sometimes  granular,  and  exhibit  traces  of  nuclei,  especially  I think  in  their  early 
stage,  but  mostly  appear  as  large,  delicate  and  quite  transparent  vesicles,  which  often 
escape  from  their  bed  of  granular  matter,  and  collect  in  the  central  canal,  along 
which  they  glide  rapidly  when  subjected  to  some  degree  of  pressure  ; the  diameter 
of  these  varies  frotn  to  of  an  inch  ; they  are  particularly  remarkable  from 

the  circutnstance  that  the  secretion  does  not  form  in  them,  but  under  their  influence 
probably  in  the  surrounding  granular  matter.  In  most  instances  the  layer  of  granular 
matter  is  of  the  same  appearance  in  its  whole  thickness,  but  occasionally  I have 
noticed  that  the  stratum  in  contact  with  the  homogeneous  tunic  was  quite  pale, 
while  that  bounding  the  central  canal  was  more  or  less  deeply  tinged  with  yellow, — 
an  interesting  difference,  which  would  seem  to  indicate  a gradual  evolution  of  the 


MDCCCXLIX. 


Q 


114 


DR.  C.  H,  JONES  ON  THE  STRUCTURE 


material  of  the  secretion  from  a previously  formed  granular  blastema.  The  contents 
of  the  tubes  are  for  the  most  part  free  in  the  cavity,  and  form  a continuous  layer 
along  the  wall ; but  sometimes,  especially  in  the  sacculated  tubes  of  the  fly,  the  cells 
and  granular  matter  form  separate  masses,  though  these  are  not  I think  surrounded 
by  envelopes*.  The  central  canal  varies  much  in  width  ; sometimes  it  is  very  narrow 
or  obstructed  with  oily  or  biliary  matter,  in  other  cases  it  is  equal  to  half  the  dia- 
meter of  the  tube. 

Directing  our  attention  now  to  the  so-called  adipose  tissue,  which  I will  venture 
to  name  the  parenchymal  portion  of  the  liver,  it  is  to  be  observed  that  it  varies  a 
good  deal  both  in  its  extent  and  in  its  general  appearance  in  different  instances ; 
moreover,  it  is  not  always  uniform  throughout,  but  presents  in  different  parts  succes- 
sive stages  of  development.  In  its  simplest  and  primary  state,  it  appears  as  a pale, 
granular  and  amorphous  blastema,  containing  numerous  large  cells,  the  average 
diameter  of  which  is  y^th  of  an  inch  ; these  are  provided  with  a distinct  envelope 
enclosing  well-formed  nuclei  and  granular  matter  of  a yellowish  tinge.  Very  nume- 
rous young  cells  are  also  present  in  the  blastema  ; they  are  nucleated,  and  contain 
only  pale  granular  matter ; their  diameter  varies  from  3 _ 2^o¥o  of  an  inch  ; lastly,  oil- 
globules  of  a greenish  yellow  tinge,  some  large  and  others  of  minute  size  grouped 
together,  are  also  found  in  this  material ; these  seem  clearly  to  arise  from  the  blas- 
tema and  not  to  be  produced  in  cells,  in  which  they  are  never  found.  Following  on 
now  the  development  of  the  parenchyma,  we  find  that  a mass  of  granular  blastema, 
in  which  lie  both  young  and  fully-formed  cells,  assumes  a definite  form,  its  margin 
becomes  even  and  invested  by  an  homogeneous  membrane  ; thus  we  have  produced 
vesicles, or  short  tubes  of  various  size  and  shape,  which  coalesce  very  irregularly  with 
each  other,  and  form  a kind  of  coarse  net-work.  Occasionally  the  vesicles  are  found 
free  and  unconnected  with  others  ; sometimes  also  they  are  replaced  more  or  less 
completely  by  long  tubes,  which  might  easily  be  mistaken  for  the  hepatic  tubes  them- 
selves. The  contents  of  the  vesicles  or  tubes  vary  a good  deal ; in  Caterpillars  they 
are  wholly  filled  with  large  colourless  oil-drops  ; in  Butterflies,  May  bugs,  and  some 
other  insects,  they  contain  a quantity  of  yellow  biliary-looking  matter,  with  various 
proportions  of  oily  and  granular  matter.  In  some  cases  there  is  scarce  any  oily  matter 
at  all,  but  only  granular,  pale,  or  of  a yellow  tint.  The  primary  cells  may  almost  always 
be  discerned  in  the  interior  of  the  vesicles,  and  upon  them  doubtless  depend  the 
persistent  action  of  these  structures.  The  interesting  observation  of  Dr.  Williams, 
respecting  the  termination  of  minute  tracheary  ramifications  in  the  vesicles  of  moths 
and  butterflies,  I have  been  able  in  some  measure  to  confirm  : I cannot  speak  posi- 
tively as  to  the  tracheae  actually  terminating  in  the  vesicles,  but  I have  seen  them 
traversing  an  elongated  vesicle  from  one  end  to  the  other,  and  thus  holding  nearly 
as  intimate  a relation  to  the  contents  as  if  they  had  actually  terminated  in  them. 

* Dr.  Williams  describes,  as  the  constant  arrangement  of  the  contents  of  the  tubes,  large  cells  containing 
several  secondary  ones  with  granular  and  biliary  matter. 


AND  DEVELOPMENT  OF  THE  LIVER. 


115 


As  reasons  for  considering-  the  tissue  now  described  as  part  of  the  hepatic  appa- 
ratus, I may  mention, — 1st,  the  close  resemblance  which  often  exists  between  the  con- 
tents of  the  vesicles  and  those  of  the  undoubted  biliary  tubes  ; in  several  instances,  in 
fact,  they  have  appeared  to  me  identical.  2nd.  The  presence  of  distinctly  yellow 
fluid,  either  infiltrating-  the  g-raniilar  contents  of  the  vesicles,  or  united  to  oil-drops  : 
this  fluid  may  be  reasonably  supposed  to  be  of  the  nature  of  bile.  3rd.  The  existence 
of  much  g-ranular  matter,  shown  by  chemical  tests  to  be  of  albuminous  nature,  of 
granular  cells  and  nuclei  in  the  vesicles,  shows  that  they  cannot  be  regarded  as 
adipose  tissue  merely;  nor  should  we  expect  to  find  this  in  such  constancy  and  abun- 
dance in  a class  no  higher  than  that  of  Insects.  4th.  The  oily  matter  which  is  found 
in  them  is  usually  not  at  all  more  abundant  than  in  the  liver  of  many  higher  animals ; 
it  exists  also  in  a state  of  diffusion  and  combination  with  the  granular  matter,  and 
its  presence  (since  the  tissue  is  surely  not  mere  adipose)  argues  in  some  measure  in 
favour  of  its  hepatic  character,  it  being  well  known  how  prone  oily  matter  is  to 
accumulate  in  hepatic  structure.  Were  it  proved  by  chemical  tests  that  the  yellow 
fluid,  not  unfrequently  seen  in  the  vesicles,  is  truly  bile,  no  further  argument  would 
be  needed  ; of  this  however  I have  been  unable  to  obtain  positive  evidence  ; yet  once 
I observed  the  yellow  tint  to  be  decidedly  deepened  by  nitric  acid,  and  from  the 
action  of  this  reagent  and  sulphuric  acid  in  other  instances,  I am  pretty  well  satisfied 
that  albumen  and  oily  matter  are  not  the  only  contents  of  the  vesicles. 

The  above  arguments,  though  far  from  conclusive  in  favour  of  the  opinion  I have 
adopted,  are  not  without  weight  ; and  I will  only  add,  that  if  this  view  should  prove 
correct,  an  analogy  will  obtain  between  the  hepatic  apparatus  of  the  Leech  and  that 
now  described  as  existing  in  Insects. 

The  structure  of  the  liver  in  Crustaceans  is  so  well  known,  and  has  been  so  well 
described,  that  I can  add  nothing  to  our  knowledge  respecting  it ; I would  remark, 
however,  that  the  large  quantity  of  free  oily  matter  which  is  found  in  the  follicles  of 
this  class,  must  be  regarded  as  an  indication  both  of  the  feeble  intensity  of  the  respi- 
ratory process,  and  also  that  the  secretion  is  not  to  be  regarded  as  in  any  great 
degree  excrementitious,  since  it  would  not  then  be  found  accumulating  in  such  quan- 
tity. Before  passing  on,  however,  I must  particularly  allude  to  one  interesting  in- 
dividual which  is  ranked  with  this  class,  the  Daphnia  monoculus : this  little  creature, 
from  the  transparency  of  its  shell,  and  the  simplicity  of  its  organization,  is  a most 
favourable  object  for  examination.  Any  one  who  would  study  the  phenomena  of 
muscular  action  in  the  living  fibre  to  advantage,  should  not  omit  to  examine  a living 
specimen  of  this  species  ; striped  fibres  exist  in  the  larger  ones,  and  the  oscillating 
waves  of  contraction  during  the  action  of  the  fibre  may  be  distinctly  observed.  The 
hepatic  apparatus  in  the  Daphnia  I believe  to  consist  of  large  cells  whose  diameter 
is  about  7-looth  of  an  inch  ; these  are  chiefly  aggregated  round  the  intestine,  but 
exist  also  in  other  parts  ; they  have  a distinct  envelope,  which  encloses  a transparent 
fluid  and  a large  reddish  yellow  oil-drop,  with  one  or  two  smaller  ones ; a nucleus  is 

Q 2 


116 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


sometimes  discernible,  especially  when  the  secretion  is  in  small  quantity.  These 
cells  usually  cohere  together,  yet  retaining  perfectly  their  separate  outline ; but  some- 
times the  groups  seem  to  become  fused  together,  and  to  form  a mass  which  is  applied 
against  the  intestinal  wall  by  a covering  membrane.  It  seems  quite  certain  that  these 
cells  are  naked,  and  uncontained  in  any  follicular  offsets  from  the  intestine  ; nor 
does  there  appear  to  be  any  provision  for  the  transmission  of  the  secretion  thither  ; 
that  they  perform  the  function  of  a liver  is  I think  highly  probable  ; their  appearance 
is  generally  such  that  one  can  scarcely  hesitate  to  believe  them  to  be  agents  of 
biliary  secretion,  and  I cannot  find  any  other  apparatus  which  seems  at  all  adapted 
to  fulfill  such  an  office.  However,  I must  state  that  in  some  cases,  especially  when 
the  Daphnia  is  laden  with  ova,  these  cells  are  almost  devoid  of  their  biliary-looking 
contents,  and  are  much  less  manifest,  though  even  then  themselves  or  their  nuclei 
are  discernible  more  or  less  clearly.  IStill,  as  it  is  impossible  to  believe  that  they  ean 
be  merely  adipose  tissue,  I regard  them  as  of  hepatic  nature,  and  would  refer  to  them 
as  an  interesting  example  of  a purely  parenchymal  hepatic  organ. 

As  a specimen  of  the  liver  among  Arachnidans,  I believe  that  of  the  common  house 
spider  may  be  referred  to ; here  the  liver  is  very  bulky  indeed,  occupying  the  greater 
part  of  the  pouch-like  abdomen ; it  is  of  a dull  yellowish-white  colour.  In  structure 
it  consists  of  short  csecal  follicles  very  closely  set  together,  about  -g^th  of  an  inch  in 
diameter  ; each  of  these  is  bounded  by  a well-marked  limitary  membrane,  and  stuffed 
with  opake  contents.  The  cells  in  the  interior  of  the  follicles  measure  about 
to  iwfh  of  an  inch ; they  have  a very  delicate  envelope,  and  contain  a quantity  of 
opake  oily-looking  matter,  with  one  or  more  granular  but  highly  refracting  vesicles; 
these  are  usually -3:r^^oth  of  an  inch  in  diameter,  and  appear  subsequently,  when  set 
free,  to  undergo  development  into  secreting  cells.  There  is  a good  deal  of  free  oily 
matter,  but  very  little  trace  of  bile  pigment ; the  oily  matter  very  often  appears  in 
the  form  of  groups  of  small  equal-sized  vesicles  of  an  inch  diameter,  which 

almost  seem  to  be  enclosed  in  a definite  envelope  ; this  may  be  the  commencement 
of  the  formation  of  nuclei  or  young  cells  under  the  favouring  physical  conditions, 
which  Ascherson  has  pointed  out.  The  large  size  of  the  gland  in  this  class  is  worth 
noticing,  as  well  as  the  character  of  its  contents,  which  consist  principally  of  granular 
and  oily  matter. 

Among  the  various  families  of  the  Mollusca,  the  follicular  type  of  arrangement  of 
the  liver  obtains,  I believe,  universally ; the  gland  is  remarkable  in  most  cases  for  its 
large  size,  and  frequently  for  the  deep  colour  of  its  elaborated  contents.  In  most 
cases  the  basement  membrane  of  the  follicles  is  extremely  distinct,  but  occasionally 
it  is  very  delicate,  and  even  its  existence  has  sometimes  appeared  to  me  doubtful; 
this  led  me  originally  to  believe  that  the  presence  of  the  basement  membrane  was 
not  essential  to  the  act  of  secretion,  but  that  its  function  was  of  a purely  mechanical 
nature,  supporting  the  secreting  cells,  and  preserving  constantly  a passage  to  the 
excretory  duct.  Subsequent  observations  have  quite  confirmed  this  opinion,  by 


AND  DEVELOPMENT  OF  THE  LIVER. 


117 


acquainting-  me  with  several  instances  where  it  is  certainly  absent  from  glandular 
structure;  thus,  in  the  pancreas  of  a pigeon,  I recently  ascertained  the  total  absence 
of  limitary  membrane  from  the  ultimate  vesicles,  the  epithelium  being  arranged  into 
follicle-shaped  masses  and  tubes,  the  form  of  which  was  solely  preserved  by  the 
cohesion  of  the  particles  together.  In  the  Common  Oyster  {Ostrea)  I notieed  a 
similar  instance ; here,  besides  the  well-known  follicular  liver,  there  is  a thin  lamella 
of  reddish  brown  aspect,  which  lies  between  the  mass  of  the  liver  and  ovary  and  the 
adductor  muscle  in  contact  with  the  intestine,  to  which  it  adheres  pretty  firmly.  In 
structure  this  consists  of  numerous  cells  aggregated  together,  and  set  as  it  were  in 
an  imperfectly  fibrous  tissue ; these  cells  measure  about  i smooth  of  an  inch  diameter, 
and  are  provided  with  an  envelope  enclosing  biliary -looking  granules,  which  some- 
times fill  them  completely:  nuclei  are  rarely  to  be  seen  in  them,  but  free  nuclei  and 
young  cells  occur  in  the  uniting  tissue.  Now  these  cells,  which  seem  to  belong  to 
the  hepatic  apparatus,  from  the  nature  of  their  contents,  are  certainly  not  contained 
in  follicles  or  any  envelopes  of  limitary  membrane,  but  lying  interstitially  fulfill  with- 
out doubt  a work  of  secretion.  This  view  of  the  non-essentiality  of  the  basement  tissue 
was  promulgated  some  years  ago  by  the  distinguished  physiologist  who  gave  the 
membrane  its  name  and  pointed  out  its  wide-spread  extent.  To  illustrate  a condition 
of  the  liver  not  uncommon  among  Mollusca,  I may  mention  the  examination  of  a Fresh- 
water Snail  {Limnceus  stagnalis),  which  I made  during  the  cold  spring  of  last  year ; 
the  organ  was  of  very  dark  aspect  and  soft  consistence,  and  its  basement  tissue  was 
scarcely  discernible;  the  secreting  structure  consisted  of  a large  quantity  of  amor- 
phous and  biliary  matter  in  a free  state,  with  numerous  cells,  some  of  which  exhibited 
an  envelope,  an  interior  nucleus,  and  granular  or  biliary  contents  ; others  were 
merely  pale  granular  bodies  : these  cells  seem  to  originate  as  delicate  vesieles  having 
a mean  diameter  of  2-^^th  of  an  inch  ; they  acquire  pale  granular  contents,  and 
probably,  at  some  period  of  their  existence,  nuclei ; but  from  observation  of  this  and 
several  others  of  the  lower  animals,  it  has  seemed  difficult  to  believe  that  tlie  energy 
of  the  cell  is  always  dependent  on  the  presence  of  a nucleus.  In  the  higher  animals 
I think  this  is  certainly  the  case,  and  yet  there  would  appear  even  in  them  to  be  an 
exception  in  the  fat  cells,  which  vary  so  much  in  size,  that  it  seems  certain  their 
growth  must  continue  long  after  the  disappearance  of  the  nucleus.  A circumstance 
which  was  very  striking  in  the  examination  of  the  liver  of  the  Limneeus,  was  the 
prodigious  quantity  of  dark  biliary  matter  which  was  accumulated  in  it ; in  many 
parts  it  seemed  as  if  the  follicle-shaped  masses  were  perfectly  solid,  converted,  one 
might  almost  say,  into  biliary  calculi.  This  state  of  the  secreting  apparatus  must 
surely  be  conceived  to  imply  a very  tardy  and  imperfect  discharge  of  the  elaborated 
matter,  and  accords  well  with  the  imperfect  character  of  the  respiratory  proeess.  In 
a Sepia,  one  of  the  most  highly  organized  among  the  Mollusca,  the  liver  was  still 
found  to  be  of  the  follicular  type;  the  terminal  cavities  were  however  very  short  and 
wide,  and  the  limitary  membrane  by  no  means  conspicuous:  the  contents  were  of 


118 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


the  usual  kind,  nuclei,  cells,  and  abundant  granular  and  oily  matter,  with  some  yel- 
low masses  which  seemed  to  consist  of  concrete  biliary  substance. 

In  concluding  this  imperfect  survey  of  the  structure  of  the  liver  in  the  Invertebrate 
sub-kingdom,  we  may  recapitulate  by  observing,  that  the  tubular  or  follicular  type 
of  arrangement  is  that  which  generally  prevails,  and  to  which  a tendency  is  almost 
invariably  manifested ; yet  it  has  been  shown  to  be  probable  in  several  instances,  that 
a more  or  less  considerable  portion  of  the  gland  is  in  a condition  which  may  be 
termed  parenchymatous,  the  secreting  structure  being  interstitially  situated  and  not 
in  connection  with  any  excretory  duct.  In  the  next  great  division  of  animals  at 
which  we  arrive,  the  hepatic  apparatus  is  constantly  distinguishable  into  a tubular 
and  parenchymatous  portion,  but  the  latter  now  preponderates  immensely,  and  the 
office  of  the  tubular  structure  is  confined  to  serving  as  an  excretory  duct;  the  evi- 
dence of  this  will  clearly  appear  in  the  class  of  Fishes,  which  will  next  be  investigated. 

With  the  exception  of  the  curious  Lancelot  {AmpMoxus),  the  liver  in  all  fishes  may 
be  stated,  on  the  authority  of  Professor  Owen,  to  be  a parenchymatoid  organ,  provided 
with  efferent  hepatic  ducts,  and  usually  a gall-bladder  and  cystic  duct,  which  pour 
the  secretion  into  the  duodenum.  The  blood-vessels  entering  the  liver  are  now  of 
different  kinds,  the  portal  vein  or  veins  supplying  altogether  the  parenchyma,  while 
the  hepatic  artery  is  devoted  principally  to  the  ducts:  this  circumstance  I think  has 
not  yet  been  fully  accounted  for  ; it  will  again  attract  our  attention  when  we  consider 
the  manner  in  which  the  secretion  is  conveyed  into  the  excretory  ducts.  Respecting 
the  actual  structure  of  the  liver  in  Fishes,  as  in  all  Vertebrate  animals,  our  knowledge 
has  hitherto  been  very  imperfect ; for  though,  if  I may  use  the  term,  the  geography 
of  the  organ  was  perfectly  set  forth  by  Mr.  Kiernan,  yet  since  we  have  become  ac- 
quainted with  the  actual  agents  in  the  process  of  secretion,  the  cells  which  elaborate 
the  bile,  and  which  constitute  so  very  large  a part  of  the  organ,  it  has  remained  a 
complete  mystery  how  the  ultimate  bile  ducts  were  disposed  with  relation  to  the  cells, 
and  in  what  manner  the  secretion  when  formed  was  conveyed  into  the  excretory  pas- 
sages. Before  giving  an  account  of  the  observations  I have  lately  made  respecting 
these  points,  I ought  perhaps  to  mention  that,  according  to  Dr.  Williams,  the  struc- 
tural arrangement  in  fishes  is  nearly  the  same  as  in  the  molluscous  tribes,  the  secreting 
cells  being  enclosed  (he  deems)  in  tubes  of  homogeneous  membrane;  this,  however, 
is  so  completely  contradicted  by  all  that  I have  seen,  that  I shall  do  no  more  than 
thus  cursorily  allude  to  it.  As  it  appears  to  me  that  in  Fishes,  the  lowest  of  the  Ver- 
tebrate classes,  we  find  the  liver  at  once  assuming  a very  different  type  of  arrange- 
ment from  any  which  it  has  hitherto  exhibited  during  our  survey  of  the  animal  series, 
it  is  evidently  a matter  of  great  importance  to  determine,  if  possible,  its  real  consti- 
tution, and  to  understand  in  what  the  essential  change  consists  which  has  produced 
so  marked  a difference  of  form  and  character ; fortunately  this  is  rendered  more  prac- 
ticable by  the  circumstance,  that  in  the  liver  of  fishes  there  is  comparatively  a small 
quantity  of  fibrous  tissue  (corresponding  to  the  capsule  of  Glisson)  diffused  throughout 


AND  DEVELOPMENT  OF  THE  LIVER. 


119 


the  gland,  which  therefore  separates  much  more  readily  into  its  elementary  parts:  I 
have  endeavoured  to  take  advantage  of  this  peculiarity  to  ascertain  the  actual  con- 
dition of  the  ultimate  hepatic  ducts,  and  I trust  that  I have  in  some  measure  suc- 
ceeded, Taking  up  a main  branch  of  the  duct,  I find  that  by  gentle  traction  and 
lacerating  the  surrounding  parenchyma,  I can  isolate  it  with  a multitude  of  ramifica- 
tions without  much  ditficulty,  and  after  gentle  washing  remove  it  to  a slip  of  glass. 
When  now  the  specimen  is  spread  out,  and  covered  with  a thin  lamina,  it  can  be 
conveniently  examined : some  of  the  branches,  especially  the  larger  ones,  are  evidently 
broken  across,  but  a great  number  of  the  smaller  ramifications  do  not  appear  to  have 
suffered  injury,  and  their  characters  may  be  thus  described.  They  have  a diameter 
of  10  00-5 oofb  of  on  inch  at  their  origin  from  the  trunks  ; they  run  a remarkably 
long  course,  giving  off  very  few  branches,  and  those  for  the  most  part  at  long  inter- 
vals, though  sometimes  a group  of  minute  branches  arise  close  together  ; they  taper 
slowly  towards  their  extremities,  which  are  found  in  various  conditions,  sometimes 
undoubtedly  closed,  with  a defined  rounded  margin  formed  by  homogeneous  mem- 
brane ; this  however  is  rare ; more  usually  the  structure  towards  the  extremity 
becomes  less  distinct,  and  it  seems  as  if  the  duct  gradually  ceased.  The  larger  ducts 
and  the  smaller  at  their  commencement  are  invested  by  a thin  layer  of  fibrous  tissue  ; 
within  this  is  a distinct  basement  membrane,  which  extends  beyond  the  fibrous  layer 
for  a variable  distance  ; sometimes  it  forms  the  rounded  closed  extremity  of  the  duct, 
but  mostly  it  becomes  gradually  faint,  and  can  only  be  supposed  to  exist  by  the  duct 
still  exhibiting  a well-defined  margin ; in  many  instances  it  certainly  ceases  some 
way  from  the  terminal  extremity.  The  contents  of  the  ducts  vary  considerably ; in 
the  larger  ones  there  may  be  either  nuclei  with  granular  matter  forming  an  epithelial 
layer,  or  very  delicate  and  pellucid  vesicles;  or  the  cavity  may  appear  transparent, 
containing  only  some  finely-mottled  substance.  Advancing  to  the  smaller  ducts,  we 
find  that  they  may  likewise  contain  pellucid  vesicles,  so  large  as  to  occupy  their  whole 
cavity,  but  more  frequently  they  are  filled  with  nuclear  granules  and  granular  matter, 
the  nuclei  again  being  often  very  indistinct,  so  that  there  is  scarce  anything  but  gra- 
nular matter  to  be  detected  ; when  they  are  in  this  condition  the  basement  membrane 
also  has  generally  disappeared,  and  the  aspect  of  the  duct,  some  way  before  its  ter- 
mination, is  that  of  a tract  of  granular  matter,  which  preserves  accurately  the  tapering 
form  and  course  of  the  original  structure.  In  some  cases  the  fibrous  coat  is  pro- 
longed further  than  usual,  being  continued  as  a filamentous  expansion  into  the  sur- 
rounding parenchyma  beyond  the  terminal  extremity  of  the  duct.  The  foregoing 
description  expresses  the  results  at  which  I have  arrived  from  numerous  dissections 
of  the  liver  in  marine  fishes ; in  the  Perch  {Perea),  however,  I have  observed  a con- 
dition of  the  ultimate  ducts  which  differs  from  that  now  described  in  some  respects, 
but  resembles  exactly  that  which  is  found  in  the  mammalian  liver;  instead  of  ap- 
pearing as  minute  cylinders  of  granular  matter  in  which  nuclei  are  scarcely  per- 
ceptible, these  ducts  consist  almost  wholly  of  small  nuclei  set  close  together  in  a 


120 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


scanty  basis  substance ; they  are  quite  devoid  of  basement  membrane,  and  measure 
s'- 3^0 00 th  of  an  inch  towards  their  terminal  extremity.  The  mode  which  I have 
adopted  of  examining  the  ducts  may  be  thought  by  some  to  be  objectionable,  on  the 
ground  that  the  extremities  of  the  ducts  must  necessarily  be  lacerated  ; but  I think  a 
careful  repetition  of  the  process  I have  indicated,  will  satisfy  the  observer  that  it 
offers  the  most  probable  means  for  deciding  the  point  in  question  ; in  fact  I know  of 
no  other  except  injection  which  can  be  adopted,  and  I am  satisfied  that  in  this  case 
the  results  of  injection  are  not  to  be  depended  on.  To  one  remarkable  character  of 
the  ducts  which  has  been  mentioned  I would  ask  especial  attention,  viz.  the  long 
course  which  the  smaller  ramifications  take  without  giving  off  branches.  I have  ob- 
served one  which  ran  ^th  of  an  inch  without  giving  off  any  branches,  and  another 
which  gave  off  only  one  branch  in  a course  of  -^oth  of  an  inch.  When  we  take  into 
consideration  this  fact,  and  remember  also  how  minute  the  terminal  extremities  of 
the  ducts  become,  and  that  they  are  not  unfrequently  seen  distinctly  closed,  it  will 
appear  quite  certain  that  the  ducts  can  have  no  actual  connection  with  the  surround- 
ing parenchyma,  so  as  to  envelope  and  contain  it  in  their  terminal  expansions,  as 
some  have  supposed.  The  real  relation  of  the  ducts  to  the  parenchyma  is,  I think, 
well  shown  by  a peculiarity  in  their  condition  which  I have  noticed  as  of  tolerably 
frequent  occurrence  ; when  this  exists  there  are  found  in  the  parenchyma  numerous 
masses  of  more  or  less  deep  biliary  tinge,  consisting  apparetitly  of  large  yellow  gra- 
nules enclosed  in  an  envelope  ; when  a duct  is  dissected  out,  these  yellow  masses  are 
found  adhering  to  it  at  various  parts  of  its  circumference  ; they  are  manifestly  not 
in  the  cavity  of  the  duct,  but  simply  adherent  to  it.  That  these  yellow  masses  origi- 
nate in  the  secreting  parenchyma  is  I think  indubitable ; they  evidently  consist  of 
biliary  matter  ; but  this  seems  to  have  undergone  some  change,  which  has  rendered  it 
incapable  of  being  readily  absorbed  by  the  ducts,  and  it  thus  remains  on  the  exterior, 
indicating  as  it  were  the  route  it  would  normally  pursue.  I may  here  describe  some 
remarkable  structures  which  I have  found  in  the  liver  of  the  Skate  {Raia  Bails),  and 
respecting  which  1 am  rather  in  doubt  whether  they  belong  to  the  parenchyma  or  the 
ducts  ; these  are  vesicles  of  oval  or  subcircular  form,  measuring  from  to  3^th  of 
an  inch  in  diameter  ; they  have  a distinct  envelope  of  homogeneous  membrane,  and 
a central  cavity,  which  does  not  occupy  more  than  half  the  diameter  of  the  vesicle ; 
the  intervening  substance  between  the  wall  and  the  cavity  presents  no  distinct  struc- 
ture, but  only  some  traces  of  concentric  layers  with  a few  nuclear  corpuscles  ; the 
aspect  of  the  vesicles  is  such  as  to  imply  that  they  are  filled  with  some  substance 
having  a high  refractive  power,  which  is  probably  of  oily  nature,  derived  from  that 
which  is  so  abundantly  diffused  throughout  the  parenchyma.  These  vesicles  are 
often  found  free,  and  unconnected  with  any  other  structures;  they  appear  to  be 
scattered  throughout  the  parenchyma,  but  are  sometimes  at  least  involved  in  the 
fibrous  sheaths  of  the  ducts,  so  as  to  remain  adherent  to  them  ; what  their  function 
may  be  is  quite  hypothetical ; I can  only  conjecture  that  they  may  serve  as  reser- 


AND  DEVELOPMENT  OF  THE  LIVER. 


121 


voirs  in  part  for  the  immense  quantity  of  oily  matter  which  is  produced  in  the 
gland. 

Turning  now  to  the  examination  of  the  parenchyma  of  the  liver  in  Fishes,  it  may 
be  stated  that  it  does  not  usually  present  a very  marked  division  into  lobules ; this 
however  is  often  indicated  by  the  branching  of  the  vessels,  which  do  not  run  in  inter- 
lobular fissures,  such  as  exist  in  the  liver  of  mammals.  The  term  parenchyma  is  in 
the  greater  number  of  instances  exactly  expressive  of  the  condition  of  the  secreting 
portion  of  the  hepatic  apparatus  in  fishes,  it  is  truly  a substance  poured  among  and 
upon  the  vessels  and  ducts,  filling  up  completely  the  interstices  between  them,  and 
forming  together  with  them  a solid  mass ; its  actual  state  may  vary  a good  deal ; 
sometimes  the  greater  part  consists  of  perfect  cells  with  distinct  envelopes,  and  there 
is  only  a small  quantity  of  free  nuclei  with  granular  and  oily  matter ; at  other  times 
these  are  found  to  predominate,  and  but  few  perfect  cells  are  to  be  detected ; in  this 
case  however  we  very  commonly  observe  a tendency  to  the  formation  of  cells,  the 
granular  and  oily  matter  being  aggregated  into  cell-like  masses,  which  either  enclose 
or  have  enclosed  at  some  time  a nucleus.  The  masses  of  biliary  granules,  which  I 
have  already  mentioned  as  adhering  to  the  ducts,  occur  also  free  in  the  parenchyma; 
besides  these,  I have  found  in  the  Mackerel  {Scombriis  Scomber),  and  also  in  the 
Flounder  {Platessa  Jtesus),  some  peculiar  cells  which  are  perhaps  of  the  same  nature 
as  the  above-mentioned  masses  ; they  are  larger  than  the  secreting  cells,  of  a perfectly 
circular  form,  and  contain,  within  a well-marked  envelope,  from  three  to  five  oval  or 
subcircular  vesicles,  which  have  often  a nucleolar  corpuscle  in  their  centre,  and 
possess  a high  refractive  power;  these  cells  lie  free  in  the  midst  of  the  parenchyma, 
often  forming  small  groups,  which  are  imbedded  in  yellowish  granular  matter. 
The  Flounder  furnishes  an  exception  in  some  measure  to  the  rule,  that  the  liver  of 
fishes  is  not  divided  into  lobules  by  fissures ; the  last  twigs  of  the  portal  vein  may  be 
distinctly  traced  running  in  canals  and  short  fissures  in  thin  sections  of  the  organ, 
these  canals  being  much  wider  than  the  vessels  contained  in  them  ; hence  arises  in 
certain  conditions  of  the  gland  a remarkable  disposition  which  is  well  worthy  of 
notice.  I have  usually  found  the  parenchyma  of  the  liver  in  this  fish  of  a yellowish 
white  colour,  and  very  opake  from  the  great  quantity  of  oily  matter  contained  in  it ; 
but  sometimes  it  is  found  much  more  transparent  and  of  a^  redder  tinge  ; in  the  former 
of  these  conditions  the  canals  and  fissures  are  comparatively  empty,  but  in  the  latter 
they  are  filled  with  cells  of  about  the  same  size  as  those  of  the  parenchyma,  but 
more  opake  and  of  a darker  aspect  from  the  oily  nature  of  their  contents.  The  inter- 
pretation which  I would  offer  of  this  appearance  is,  that  in  this  state  the  parietal  cells 
of  the  canals  and  fissures  do  not  readily  dehisce  and  discharge  their  contents  into 
the  cavity,  from  whence  they  may  be  absorbed  by  the  excretory  ducts,  but  encroach 
upon  and  fill  it  up  : we  shall  find  in  Mammalia  instances  of  a somewhat  similar 
occurrence,  which  appear  to  me  particularly  significant  of  the  real  constitution  of 
the  liver. 


MDCCCXLIX. 


R 


122 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


An  important  circumstance  which  cannot  but  arrest  the  attention  in  examining 
the  livers  of  many  fishes,  especially  those  of  the  Skate  and  Cod,  is  the  very  large 
amount  of  oily  matter  which  is  manifestly  in  a free  state  ; this,  as  we  have  on  former 
occasions  remarked,  indicates  a low  intensity  of  the  respiratory  process,  and  also 
serves  as  a further  proof  of  the  correctness  of  the  view  here  taken  of  the  structure  of 
the  liver ; for  were  this  abundant  oily  matter  free  in  the  cavities  of  ducts,  it  should 
surely  constitute  in  great  part  the  contents  of  the  gall-bladder,  and  so  marked  a 
difference  would  not  exist  between  the  dark-green  fluid  found  in  that  receptacle,  and 
the  dead  white  of  the  adjacent  parenchyma  of  the  liver.  Doubtless  the  excretory 
ducts  separate,  by  a process  of  vital  absorption,  the  bile  from  the  oily  matter  in  which 
they  are  bathed. 

Among  Reptiles  I have  examined  the  Common  Snake  {Coluber  natrix),  the  Fresh- 
water Tortoise  {Emys  europced),  the  Turtle  {Chelonia  my  das)  ^ the  Newt  {Triton  crista- 
tus),  the  Frog  {Rana  temporaria)  and  the  Toad  {Bufo  vulgaris)  ; in  all  these  the  liver 
is,  Kar  e^oyjiv,  a Solid  gland,  the  capillary  network  extending  equally  in  every  direction : 
the  coats  of  the  capillaries  are  remarkably  strong,  and  there  can  be  no  better  oppor- 
tunity than  is  here  presented  for  examining  their  structure,  which  corresponds  pretty 
closely  with  that  figured  by  Henle.  In  most  of  these  animals  I have  examined  the 
ducts  by  dissecting  them  out  in  the  way!  have  described,  but  by  no  means  with  such 
satisfactory  results  as  I have  obtained  in  fishes ; this  depends  on  the  greater  strength 
of  the  fibrous  and  other  tissues  composing  the  framework  of  the  gland  ; however,  in 
the  Newt,  Snake  and  Toad,  I have  been  able  to  determine  sufficient  respecting  the 
ducts,  to  satisfy  me  that  they  do  not  differ  in  any  essential  circumstance  of  structure  or 
arrangement  from  those  of  fishes : thus  it  is  quite  certain  that  they  bear  only  a small 
proportion  to  the  mass  of  secreting  parenchyma ; they  can  be  traced  running  a long 
course  through  it,  and  giving  off  very  few  branches,  and  in  one  or  two  instances  they 
have  clearly  been  seen  to  terminate  by  closed  extremities.  In  structure  they  consist 
of  a delicate  epithelium  with  an  investing  layer  of  basement  membrane,  and  often  of 
fibrous  tissue ; these  latter  elements  are  often  wanting  in  the  smaller  ducts,  whose 
diameter  varies  from  3 to  loooth  of  an  inch  ; towards  their  terminal  extremity  also  the 
tubular  character  is  often  completely  lost,  and  the  nuclei  become  indistinct,  so  that 
there  remains  only  a tract  of  granulo-amorphous  matter  containing  some  minute  oil- 
drops,  which  is  soon  lost  in  the  surrounding  parenchyma.  This  mode  of  termination 
in  reptiles,  as  well  as  in  fishes,  is  manifestly  equivalent  to  terminating  by  a closed 
caecal  extremity,  as  far  as  regards  a direct  communication  with  the  secreting  paren- 
chyma. 

In  none  of  the  Reptilia  that  I have  examined  has  there  appeared  any  manifest 
tendency  to  a division  of  the  parenchyma  into  lobules  ; it  consists  of  delicate  cells, 
free  nuclei  and  granular,  with  a small  proportion  of  oily  matter : in  the  Snake  these 
are  arranged  into  masses  of  a definite  form,  which  are  disposed  so  as  to  represent 
short  linear  series  coalescing  to  form  a plexus,  but  in  the  others  they  merely  occupy 


AND  DEVELOPMENT  OF  THE  LIVER. 


123 


and  fill  the  interstices  of  the  capillary  network.  Sometimes,  as  in  the  Toad  and  Snake, 
the  greater  part  of  the  secreting  structure  is  in  the  form  of  free  nuclei  and  granular 
matter,  with  globules  of  secretion ; in  others,  as  the  Tortoise,  Frog  and  Newt,  the 
perfect  cells  are  more  abundant ; these  are  usually  very  delicate,  appearing  often  like 
transparent  spaces  in  the  midst  of  the  darker  surrounding  substance.  Besides  these, 
the  ordinary  elements  of  secreting  structure,  there  are  constantly  found  in  all  the 
animals  I have  mentioned,  excepting  the  Snake,  a great  number  of  rather  large  dark 
yellowish  corpuscles  imbedded  in  the  parenchyma ; these  in  the  Eft  measured  from 
Ty^  to  iT^th  of  an  inch  ; their  form  is  usually  circular  or  rather  oval,  but  sometimes 
irregular  when  several  have  coalesced  together  ; their  margin  is  generally  well-defined, 
they  lie  quite  separate  and  unconnected  with  any  other  structures.  I have  not  been 
able  to  determine  exactly  the  mode  of  their  production ; sometimes  it  has  appeared 
that  a number  of  dark  yellow  granules  were  grouping  themselves  together  to  form  a 
circular  mass ; they  exhibited  very  active  molecular  motion,  but  were  enclosed  by  no 
envelope ; in  other  instances  a delicate  envelope  is  distinctly  demonstrable,  and  once 
I have  observed  a mass  of  similar  granules  enclosed  in  a cell  with  envelope  and  nucleus. 
It  seems  on  the  whole  probable  that  these  dark  corpuscles  are  produced  in  some  way 
by  the  agency  of  cells,  or  perhaps  by  their  nuclei  alone,  and  it  is  scarcely  doubtful  that 
they  must  be  considered  as  products  of  hepatic  secretion,  though  an  eminent  chemist, 
whom  I requested  to  examine  them,  was  unable  to  discover  in  them  the  usual  reac- 
tions of  bile.  These  remarkable  biliary  concretions  (for  so  I think  we  may  call  them), 
occurring  in  the  liver  of  reptiles,  are  evidently  identical  in  their  nature  and  import 
with  the  yellow  masses  described  in  the  liver  of  fishes  ; both  are  doubtless  indications 
of  imperfect  excretory  action  ; but  the  deep,  almost  black  colour  of  the  retained  pro- 
duct in  the  reptile,  and  the  great  deficiency  of  oily  matters  in  the  gland,  as  compared 
with  that  of  the  fish,  seem  to  lead  to  the  conclusion,  that  a vicarious  relation  subsists 
between  the  colouring  and  fatty  principles  of  the  hepatic  secretion  ; and  this  is  borne 
out  by  the  appearance  which  is  presented  in  complete  fatty  degeneration  of  the 
human  liver,  compared  with  the  same  in  a state  of  biliary  congestion,  the  olive  tint 
of  the  latter  condition  being  replaced  by  the  dull  yellowish  white  of  the  former. 

In  Birds  the  liver  is  of  a crisper  texture,  and  much  lighter  colour  than  in  most 
reptiles ; it  presents  decided  indications  of  a lobular  arrangement,  and  in  thin  sections 
portal  canals  may  be  easily  traced  dividing  into  fissures.  Its  parenchyma  varies  in 
character ; in  a pigeon  it  was  remarkably  free  from  oil-globules,  and  consisted  almost 
entirely  of  nuclei  and  granular  matter,  no  perfect  cells  being  discernible  ; in  a swan 
{Cygnus  olor)  the  secreting  substance  was  of  a dark  greenish  colour,  owing  to  the 
presence  of  biliary  matter,  and  chiefly  disposed  so  as  to  form  masses  having  a plexiform 
arrangement ; in  a duck  {Anas  hoschus)  the  parenchyma  was  equally  destitute  of 
perfect  cells,  consisting  entirely  of  nuclei  and  granular  matter,  with  diffused  oily 
particles ; there  were  also  numerous  groups,  as  well  as  separate  molecules  of  biliary 
matter,  lying  free  in  the  parenchyma,  and  also  in  the  fissures  by  which  it  was  traversed, 

R 2 


124 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


These  and  several  of  the  observations  previously  recorded  render  it,  I think,  certain 
that  the  formation  of  perfect  cells  is  not  necessary  to  the  act  of  secretion,  the  nuclei 
alone  are,  doubtless,  adequate  to  produce  the  necessary  change  in  the  exuded  plasma ; 
but  if  it  be  intended  that  the  structure  shall  have  a certain  degree  of  permanence, 
then  it  is  surrounded  with  an  envelope,  to  isolate  and  confine  in  some  measure  the 
elaborated  contents. 

In  the  Pigeon,  the  ducts,  when  dissected  out,  were  found  to  terminate  very  much 
in  the  same  manner  as  they  do  in  the  liver  of  mammals  ; thus  one  small  branch,  r^g^tli 
of  an  inch  in  diameter,  appeared  to  terminate  by  a closed  extremity ; its  walls  consisted 
of  nuclei  set  close  together  in  an  amorphous  or  finely  granular  basis-substance,  and 
were  not  invested  by  any  basement  membrane ; another  branch,  j-^^th  of  an  inch 
in  diameter,  was  seen  in  one  part  of  its  course  to  have  a fine  homogeneous  tunic 
enclosing  nuclei  and  granular  matter ; it  terminated  by  losing  its  tubular  character, 
and  becoming  resolved  into  a tract  of  very  perfect  and  beautiful  nuclei,  which  still 
retained  the  original  form  of  the  duct.  In  an  owl  I found  one  or  two  minute  ducts 
which  certainly  seemed  to  terminate  by  closed  extremities  ; they  consisted  principally 
of  a finely  granular  substance  containing  small  greenish  yellow  oil-drops  ; nuclei  were 
seldom  visible  in  them,  and  the  basement  membrane  ceased  before  their  terminal 
extremity.  In  an  examination  of  a duck  I obtained  some  very  perfect  specimens  of 
the  ultimate  ducts ; they  were  often  long  and  slender,  about  y^^th  of  an  inch  in 
diameter,  and  tapered  very  gradually  to  their  extremity,  which  I think  was  in  some 
instances  certainly  closed.  In  structure  they  resembled  pretty  nearly  those  of  the 
Owl,  appearing  as  cylindrical  tracts  of  granular  matter,  but  the  nuclei  in  them  were 
rather  more  distinct ; in  one  of  them  which  I have  figured  it  is  well  seen  how  the 
basement  tissue,  distinct  at  one  part,  gradually  fades  away,  and  is  lost  as  the  duct 
diminishes  toward  its  terminal  extremity.  From  these  observations  there  can  be  no 
doubt  that  the  liver  in  birds  is  of  the  same  type  of  structure  as  that  which  we  have 
found  to  prevail  in  the  two  lower  Vertebrate  classes;  we  may  remark  again,  in  these 
animals  of  rapid  circulation  and  active  respiration,  how  the  character  of  the  oxidizing 
process  affects  the  condition  of  the  liver,  a very  small  quantity  of  oily  matter  only 
existing  in  the  parenchyma  of  the  Pigeon,  a bird  of  vigorous  flight,  while  that  of  the 
stately  and  slow-moving  Swan  presents  evident  traces  of  retained  secretion. 

Lastly,  we  arrive  at  the  Mammalia,  in  whom  each  of  the  glandular  organs  has  a 
definite  and  unvarying  type  of  structural  arrangement.  The  tubes  of  the  testis  and 
kidney,  the  vesicles  of  the  salivary  and  allied  glands,  are  familiar  to  our  thoughts 
and  observations,  but  the  well-defined  and  closely-crowded  cells  of  the  liver  are  yet 
scarcely  acknowledged  to  constitute  a parenchyma  in  the  true  acceptation  of  the 
word,  several  yet  seeming  to  incline  to  the  belief  that  they  are  contained  in  some  way 
in  terminal  expansions  of  the  ducts.  In  endeavouring  to  determine  the  long-mooted 
question,  as  to  the  mode  in  which  the  biliary  ducts  terminate,  I have  of  course  re- 
sorted to  the  method  of  injection,  but  except  in  the  case  of  the  Pig,  I cannot  think 


AND  DEVELOPMENT  OF  THE  LIVER. 


125 


that  I have  obtained  any  satisfactory  results ; a better  prospect  of  success  is  I be- 
lieve afforded  by  the  mode  of  examination  I have  already  described,  in  which  actual 
recognition  of  structure,  and  not  appearance  only,  is  accepted  as  decisive  evidence 
of  the  presence  of  the  duct.  Before  proceeding  to  describe  the  results  of  my  dissec- 
tions of  the  ducts,  I may  state  what  appears  to  me  to  be  an  unexceptionable  conclu- 
sion drawn  from  injection  of  the  hepatic  ducts  in  the  Pig.  Here,  when  a successful 
injection  has  been  made  in  the  double  mode  so  successfully  employed  by  Mr.  Bowman, 
the  lobules  are  seen  to  be  definitely  marked  out  by  yellow  lines  or  tracts,  corresponding 
to  and  exactly  occupying  the  “ fissures”  and  “ spaces.”  In  several  beautiful  specimens 
thus  prepared,  the  yellow  line  presents  a most  defined  edge,  and  does  not  trench  in 
the  slightest  degree  upon  the  interior  of  the  lobule ; from  this  I cannot  but  conclude 
that  no  tubular  duct  penetrates  the  secreting  structure ; for  were  such  the  case,  it  is 
impossible  that  the  injection  should  not,  to  some  extent  at  least,  have  coloured  the 
substance  of  the  lobule.  Hitherto  I believe  no  particular  description  has  been  given 
of  the  structure  of  the  minute  branches  of  the  hepatic  duct ; the  larger  ones  are 
known  to  have  a columnar  epithelium  resting  on  a subjacent  basement  membrane, 
which  is  strengthened  by  an  investing  layer  of  fibrous  tissue.  In  the  minute  branches, 
which  seem  to  be  approaching  their  termination,  and  which  sometimes  can  be  isolated 
and  examined  in  the  most  satisfactory  manner,  the  epithelial  particles  are  remarkably 
modified;  they  can  scarcely  be  said  to  exist  as  separate  individuals,  but  rather  their 
nuclei,  which  are  often  large  and  distinct,  are  set  close  together  in  a subgranular  or 
homogeneous  basis-substance.  In  ducts  where  this  condition  of  epithelium  exists, 
there  is  seldom  any  distinct  trace  of  basement  membrane,  the  margin,  though  suffi- 
ciently even,  yet  exhibiting  the  bulging  outlines  of  the  component  nuclei;  still  less  is 
there  any  proper  fibrous  coat,  though  the  ducts  may  be  more  or  less  involved  in  the 
filamentary  expansions  of  the  capsule  of  Glisson.  Ducts  of  this  character  have  usually 
a diameter  of  about  iwo^h  of  an  inch  ; they  can  be  sometimes  followed  for  a consi- 
derable distance,  without  being  seen  to  give  off  any  branches,  or  to  diminish  much  in 
calibre.  Their  mode  of  termination  is  various ; several  have  been  distinctly  seen  to 
terminate  by  rounded  and  closed  extremities,  which  have  nearly  the  same  diameter 
as  the  duct  itself ; others  seem  to  lose  their  tubular  character,  their  nuclei  become 
less  closely  set  together,  and  the  uniting  substance  more  faintly  granular  and  indefi- 
nite ; the  duct  in  short  gradually  ceases,  losing  all  determinate  structure.  In  some  of 
rather  minute  size,  3-2^0 ooth  of  an  inch  in  diameter,  the  exterior  form  remains 
distinct,  but  the  canal  is  almost  obliterated  by  the  close  approximation  of  the  nuclei 
of  the  opposite  walls.  These  structures  now  described  I believe  to  be  truly  the 
terminal  branches  of  the  hepatic  duct,  from  which  they  certainly  originate  ; they  seem 
gradually  to  lay  aside  the  several  component  tissues  of  the  larger  ducts,  the  fibrous 
coat  blending  with  the  ramifications  of  Glisson’s  capsule,  the  basement  membrane 
imperceptibly  ceasing,  and  the  epithelium  being  resolved  at  last  into  its  simple  fun- 
damental nuclei.  The  above  account  has  been  taken  chiefly  from  examination  of 


126 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


the  liver  of  the  Sheep,  but  in  the  Human  subject  and  in  the  Pig  I have  made  obser- 
vations precisely  similar. 

In  proceeding  next  to  speak  of  the  parenchyma  of  the  liver  in  Mammals,  I must 
recur  to  some  points  which  I have  dwelt  on  in  a previous  paper ; several  of  these 
have  been  fully  confirmed  by  my  later  observations,  but  in  respect  to  one  I have 
fallen  into  a considerable  error.  I described  (as  Mr.  Bowman  had  previously  done) 
the  cells  composing  the  lobules  as  arranged  in  long  radiating  series  around  the  inter- 
lobular vein,  the  series  however  communicating  with  each  other,  and  presenting  a 
more  or  less  decidedly  plexiform  arrangement : I observed  the  sides  of  the  lobules  to 
be  invested  by  a membrane,  which  was  continued  across  the  floor  of  the  fissure  to 
line  the  side  of  the  opposite  lobule ; this  membrane,  in  the  Rabbit  and  often  in  the 
Sheep,  is  truly  homogeneous,  and  resembles  exactly  the  basement  tissue.  I concluded 
it  to  be  such,  and  believed  that  its  presence  afforded  exact  information  of  the  mode 
in  which  the  excretory  duct  terminated,  which  would  thus  appear  to  have  expanded 
into  the  interlobular  fissure.  This  view  was  further  confirmed  by  the  observation  that 
the  supposed  basement  membrane  was  often  deficient,  the  marginal  cells  of  the 
lobules  being  then  irregularly  prominent,  and  crowded  with  secretion  globules,  which 
appeared  to  be  escaping  in  great  numbers  into  the  interlobular  fissure.  Subsequent 
examination  has  convinced  me  that  the  membrane  investing  the  lobules  is  not  really 
the  basement  tissue  of  the  ducts,  but  a continuation  of  the  capsule  of  Glisson  ; that 
however  it  is  frequently  of  homogeneous  texture,  that  it  is  also  often  absent,  and 
that  the  marginal  cells  are  then  in  the  condition  which  may  be  termed  active,  are 
points  which  repeated  examination  has  fully  confirmed.  Respecting  the  office  of  the 
interlobular  fissure  as  a receptacle  of  the  secretion,  and  pro  tanto  a portion  of  the  duct, 
I hardly  feel  able  to  make  confidently  a general  statement ; it  certainly  is  often  seen 
crowded  with  globules  of  secretion,  which  have  evidently  been  produced  by  the 
marginal  cells  of  the  lobules  ; at  other  times  it  appears  empty,  and  the  sides  of  the 
lobules  are  evenly  lined  by  the  investing  membrane  ; not  unfrequently  (at  least  in 
the  Sheep)  the  interlobular  ‘‘  fissure”  has  completely  disappeared,  and  even  the 
space”  become  contracted,  from  the  encroachment  of  the  peripheral  cells  of  the 
lobules,  so  that  the  mammalian  liver  has  then  assumed  pretty  nearly  the  condition 
of  the  undivided  liver  of  Fishes : — a conclusion  probably  not  far  from  the  truth  is,  that 
the  fissure  may  often  serve  as  a receptacle  for  the  secreted  product,  especially  when 
the  gland  is  in  a high  state  of  activity,  but  that  under  ordinary  circumstances  the 
removal  of  the  seereted  bile  may  be  effected  without  its  having  been  first  received 
into  the  fissure.  I may  here  record  an  observation  which  I made  on  the  liver  of  a 
dog  who  died  of  granular  disease  of  the  kidneys.  On  the  surface  of  a section  of  the 
organ  there  were  seen  a number  of  yellow  ramifying  lines  or  tracts,  which  were  found 
to  be  occasioned  by  the  accumulation  of  a quantity  of  yellowish  material  in  the  portal 
canals  and  fissures ; this  deposit  undoubtedly  was  in  part  of  biliary  nature,  and 
seemed  to  indicate  that  the  absorbing  action  of  the  excretory  ducts  having  been 


AND  DEVELOPMENT  OF  THE  LIVER. 


127 


checked,  the  secretion  from  the  marginal  cells  of  the  lobules  had  accumulated  in  the 
fissures  and  canals,  so  as  to  produce  the  appearance  described.  Now  that,  which 
occurred  to  an  extreme  degree  in  this  abnormal  condition,  may  very  probably  take 
place  to  a lesser  extent  when  the  gland  is  in  a healthy  state,  and  there  would  seem 
in  all  cases  to  be  a tendency  to  the  occurrence  of  something  similar.  The  theory, 
first  suggested  by  Henle  though  not  adopted  by  him,  which  I endeavoured  to  esta- 
blish in  my  previous  paper,  respecting  the  mode  in  which  the  bile,  elaborated  by  the 
cells  in  the  interior  of  the  lobule,  is  conveyed  to  the  efferent  duct  on  the  exterior, 
viz.  that  it  makes  its  way  by  transmission  from  cell  to  cell  of  a linear  series,  is  I 
think  somewhat  confirmed  by  what  I have  occasionally  observed  respecting  the  dis- 
position of  the  contents  of  the  cells  when  arranged  in  a series  ; thus  in  one  very  per- 
fect series  of  some  considerable  length,  there  was  a distinct  indication  of  a central 
canal  extending  throughout  it,  the  granular  matter  in  each  lay  in  contact  with  the 
cell-wall,  and  the  middle  part  of  the  cell  was  comparatively  free.  But  though  from 
the  examination  of  certain  livers  we  might  be  led  to  conclude  that  this  mode  of 
transmission  was  the  only  one  in  which  the  secretion  of  the  cells  was  disposed  of,  yet 
instances  are  abundantly  frequent  which  render  it  very  probable  that  there  is  another 
and  more  direct  mode  in  which  the  removal  of  the  cell  product,  prone  as  it  is  to 
accumulate,  is  provided  for.  Now  the  following  circumstance  cannot  I think  but 
arrest  the  attention  of  all  who  are  in  the  habit  of  examining  the  condition  of  hepatic 
structure,  viz.  that  the  quantity  of  free  oily  (perhaps  also  of  biliary)  matter  varies 
very  greatly ; sometimes  it  is  extremely  abundant,  at  others  scarce  any  is  to  be  found  : 
moreover  it  is  manifest,  that  the  product  of  secretion,  while  thus  freely  diffused,  is 
just  in  the  condition  which  renders  it  most  exposed  to  the  absorbing  action  of  the 
circulating  current.  If  the  materials  which  serve  as  fuel  for  respiration  are  deficient 
in  the  blood,  they  may  be  readily  absorbed  into  this  fluid,  as  it  percolates  the  lobular 
masses ; and  we  may  go  further,  and  state  that  it  is  quite  probable,  that  even  while 
the  biliary  secretion  is  contained  within  the  cell  envelope,  it  is  capable  of  being 
influenced  by  the  state  of  the  blood,  so  as  to  make  its  way  by  endosmosis,  into  the 
capillary  streams,  through  the  homogeneous  membranes  of  the  cell  and  blood-vessel. 
This  view  will  not  seem  improbable,  if  we  reflect  on  the  simple  constitution  of  the 
lobules,  where  a vast  mass  of  naked  cells  is  traversed  by  an  exceedingly  close  capil- 
lary network ; the  cells  and  the  blood  are  therefore  brought  into  the  closest  relation 
possible,  and  it  cannot  but  be  on  mere  physical  principles,  that  the  contents  of  either 
should  tend  to  intermingle.  I may  also  remark,  that  this  view  supplies  another 
reason  besides  that  suggested  by  Mr.  Simon  for  the  absence  of  the  basement  mem- 
brane, viz.  that  not  only  the  cells  may  be  more  freely  exposed  to  the  blood,  but  the 
blood  also  to  the  contents  of  the  cells.  The  above  suggestions,  founded  on  structural 
characters,  and  on  the  varying  conditions  of  the  organ,  harmonize  well  with  the  view 
which  has  lately  received  so  much  support  from  chemical  inquiry,  and  which  regards 
the  bile  as  mainly  intended  to  be  absorbed  and  returned  to  the  circulation ; they 
may  also  help  to  explain  why  the  bile  has  to  pursue  so  tardy  and  indirect  a course 


128 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


before  it  can  be  received  into  the  excretory  duct ; and  lastly,  if  correct,  they  seem  to 
establish  that  the  liver  is  not  widely  removed  from  the  class  of  g-lands  destitute  of 
efferent  ducts,  like  them  allowing  a part  of  its  elaborated  products  to  return  at  once 
into  the  blood,  from  whence  as  plasma  they  had  been  derived.  On  a future  occasion 
I trust  to  have  the  opportunity  of  examining  more  closely  into  the  function  of  the 
liver.  I may  however  at  present  remark,  that  if  the  capillary  radicles  of  the  portal 
vein  absorb  the  saccharine  and  amylaceous  matters  from  the  intestines,  it  seems  a 
wise  provision  that  the  blood  so  charged  should  percolate  intimately  a vast  mass  of 
cells,  which  may  specially  act  on  the  newly-absorbed  materials,  retain  them  if  they 
are  in  excess,  convert  them  into  biliary  compounds,  and  again  allow  them  to  return, 
as  needed,  into  the  circulating  current : this  in  fact  is  nearly  the  view  proposed  by 
Messrs.  Bouchardat  and  Sandras.  I have,  lastly,  to  speak  of  the  relation  which  the 
excretory  ducts,  before  described,  hold  to  the  lobules  of  the  parenchyma.  As  far  as 
I can  ascertain,  they  do  not  ramify  very  extensively,  at  least  both  in  the  Rabbit  and 
Sheep  many  fissures  appear  quite  destitute  of  them ; in  those  where  the  margin  is  in 
an  active  state,  the  cells  bare  and  discharging  their  contents,  the  absence  of  the  duct 
may  often  I think  be  clearly  determined;  in  others,  where  the  margin  is  still  covered 
by  the  investing  membrane,  it  is  more  difficult  to  be  certain,  but  generally  I think  it 
maybe  stated  that  they  do  not  extend  far  beyond  the  “spaces;”  here  however  I have 
in  thin  sections  several  times  distinctly  observed  small  ducts  which  terminated  by 
closed  extremities.  In  the  portal  canals  small  duct  branches  creep  over  the  surface 
of  the  parietal  lobules,  and  take  up  their  elaborated  products.  In  now  endeavouring 
to  determine  the  mode  in  which  the  biliary  secretion  formed  exterior  to  the  ducts 
arrives  in  their  interior,  we  may  recall  with  advantage  the  condition  of  the  gland,  as 
we  found  it  to  exist  in  the  class  of  Fishes.  Here  it  was  seen  that  the  excretory  ducts, 
having  coats  of  great  tenuity  and  containing  an  active  epithelium  in  their  interior, 
ran  a long  course  imbedded  in  the  parenchyma,  and  bathed  as  it  were  in  its  copious 
secretion ; moreover,  coincidently  with  the  assumption  of  the  parenchymal  form,  we 
found  that  a separate  vessel  conveying  a different  kind  of  blood  was  appropriated  to 
the  nutrition  of  the  hepatic  duct  and  its  branches,  and  it  seems  certain  that  a dif- 
ferent material  is  formed  in  the  interior  of  the  excretory  ducts,  from  that  which  is 
produced  so  abundantly  around  them.  May  it  not  therefore  be  considered  as  far 
from  improbable,  that  the  absorption  of  the  secreted  material  is  effected  by  an  action 
of  endosmotic  character,  not  however  one  of  mere  physical  kind,  but  vital,  i.e.  pecu- 
liar in  its  nature,  and  producing,  I believe,  at  the  same  time  a change  more  or  less 
considerable  in  the  fluid  absorbed*?  One  further  proof  may  be  adduced  in  the  class 

* It  may  be  observed,  that,  supposing  the  nucleus  to  be  the  essential  agent  in  the  elaboration  of  all  secretions, 
the  structural  condition  of  the  ultimate  hepatic  ducts  is  just  that,  which  is  best  fitted  for  the  office  I believe 
them  to  fulfill,  of  eliminating  from  the  product  of  the  surrounding  cells  the  bile  itself : moreover  this  condition, 
which  might  in  some  measure  be  regarded  as  the  natural  result  of  their  diminution  in  size,  corresponds  pre- 
cisely with  what  seems  to  be  required  by  the  function  ascribed  to  them, — an  accordance  such  as  is  rarely  seen 
except  in  the  actual  works  of  nature  herself. 


AND  DEVELOPMENT  OF  THE  LIVER. 


129 


of  Mammalia  of  the  relation  obtaining-  between  the  condition  of  the  liver  and  the 
amount  of  respiration:  the  cells  of  a porpoise’s  liver  were  granular  nucleated 
bodies,  containing  rarely  a single  oil-drop ; nor  was  there  more  than  a very  minute 
quantity  of  oil  in  a free  state  throughout  the  gland, — a contrast  most  complete  to  the 
condition  of  the  hepatic  parenchyma  in  its  co-inhabitants  of  the  watery  element, 
which  respire  not  by  lungs,  but  by  branchiae. 

Development. 

The  development  of  the  liver  is  described  by  Muller,  with  whom  Valentin  and 
others  agree,  as  being  formed  on  the  fourth  day  of  the  incubation  of  the  chick  by  a 
conical  protrusion  of  the  intestine,  which  soon  acquires  walls  of  considerable  thick- 
ness, in  the  substance  of  which  the  ducts  proceed  to  ramify ; some  of  the  “ biliferous 
canals”  however  being  apparently  formed  independently  in  the  blastema  itself.  A 
different  account  is  given  by  Reichert,  who  states  that  the  rudimentary  mass  of  the 
liver,  as  well  as  that  of  the  pancreas,  is  merely  a cellular  growth  from  the  surface  of 
what  he  calls  “ membrana  intermedia,”  which  appears  to  be  a layer  of  cells  deve- 
loped from  the  germinal  disc,  corresponding  to  the  vascular  and  mucous  layers,  and 
destined  to  give  origin  to  the  vertebral,  cutaneous,  and  sanguineous  systems,  and 
the  digestive  system,  with  the  exception  of  its  mucous  membrane. 

The  following  observations  fully  confirm  the  opinion  of  Reichert,  so  far  as  regards 
the  independent  origin  of  the  liver ; with  respect  however  to  some  other  points,  the 
description  which  I venture  to  offer  is  in  some  degree  different  from  any  with  which 
I am  acquainted.  On  the  morning  of  the  fourth  day  I have  found  in  the  chick  the 
chorda  dorsalis  and  the  rudiments  of  the  vertebrae  perfectly  distinct ; below  these  was 
a longitudinal  fold  with  its  convexity  downwards,  which  was  probably  one  of  the 
‘‘ visceral  laminae  towards  the  anterior  part  of  this,  and  just  behind  the  heart,  there 
was  a slight  convex  prominence,  with  a vascular  free  border,  which  appeared  as  a 
growth  from  the  germinal  membrane;  this  was  probably  the  rudiment  of  the  liver: 
no  trace  could  be  discerned  of  anything  like  an  intestine.  In  another  specimen  about 
the  same  period,  it  was  noticed  that  the  developing  vessels  were  very  patchy  and 
irregular,  that  in  some  parts  there  were  merely  spots  or  short  streaks,  and  that 
though  containing  well-formed  blood-globules,  they  did  not  appear  to  have  distinct 
parietes.  On  the  fifth  morning  the  liver  was  quite  distinct ; it  appeared  as  a some- 
what reddish  yellow  mass  situated  just  behind  the  heart,  and  presenting  a free  convex 
border  below ; above  it  ran  the  oesophagus  curving  forward  and  upwards,  behind  it 
was  the  stomach  and  the  recently  developed  intestine.  The  border  of  the  liver  was 
pretty  distinct  in  the  whole  of  its  circumference ; a narrow  space  clearly  intervened 
between  it  and  the  oesophagus  and  stomach,  and  there  did  not  appear  to  be  the 
slightest  trace  of  the  liver  being  derived  from  either  of  them  ; it  seemed  manifestly  a 
separate  and  independent  formation.  The  intestine  distinguished  from  the  oesophagus 
and  stomach  appears  to  be  developed  in  the  following  manner,  which  I think  has  not 
MDCCCXLIX.  s 


130 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


yet  been  correctly  described.  On  the  fifth  day  the  constriction  of  the  germinal 
membrane  producing  the  vitelline  duct  was  perfectly  manifest,  and  the  duct  itself 
was  filled  with  a dark  oily  mass  contained  in  a distinct  homogeneous  membrane ; this 
membrane  constituting  a complete  sheath  separated  the  cavity  of  the  vitelline  duct 
from  that  of  the  abdomen.  It  divided  into  two  canals  which  took  their  course  in 
nearly  opposite  directions  ; one  ran  forward  and  turned  sharply  upwards  just  behind 
the  liver,  and  soon  expanded  into  a somewhat  dilated  cavity.  From  this  cavity  several 
offsets  were  distinctly  traced ; one  inclined  upwards  and  a little  forwards,  widening 
as  it  proceeded,  and  soon  opened  into  a transparent  space  with  delicate  but  distinct 
parietes,  which  was  evidently  the  stomach,  as  it  opened  at  the  other  extremity  into 
the  oesophagus.  A second  offset,  which  was  very  distinct,  passed  upwards  and  back- 
wards, and  appeared  to  terminate  in  a cul  de  sac,  but  its  destination  could  not  be 
satisfactorily  determined.  From  the  anterior  part  of  the  intestinal  cavity  two  less 
distinct  offsets  could  be  clearly  traced  proceeding  into  the  liver ; the  upper  one  ap- 
peared to  divide,  but  they  could  not  be  seen  to  ramify  in  the  substance  of  the  gland. 
The  other  canal  proceeding  from  the  vitelline  duct  ran  backwards  and  upwards,  and 
seemed  clearly  to  be  developing  itself  into  the  posterior  part  of  the  intestine,  but  was 
in  a less  advanced  condition  than  that  already  described  ; at  a subsequent  period 
the  two  cseca,  which  afterwards  attain  so  considerable  a length,  were  seen  sprouting 
out  on  either  side  from  this  portion  of  the  intestine.  Both  these  canals  derived  from 
the  vitelline  duct  were  filled  with  opake  oily  contents,  so  that  their  course  was  most 
satisfactorily  traced ; they  also  presented  a distinct  homogeneous  enveloping  mem- 
brane, and  some  trace  of  an  external  layer  of  granular  aspect  which  afterwards  be- 
comes much  more  marked,  and  which  seems  to  be  derived  from  the  germinal  mem- 
brane itself. 

Towards  the  close  of  the  sixth  day  a change  had  taken  place  in  the  condition  of 
the  stomach  ; it  no  longer  distinctly  communicated  with  the  developing  intestine,  but 
appeared  as  a thick  well-defined  mass,  into  which  the  canal  of  the  oesophagus  ran, 
and  terminated  by  a marked  csecal  dilatation.  The  anterior  prolongation  of  the  vitel- 
line duct  formed  a considerable  curve  with  the  convexity  upwards,  then  descending 
became  indistinct,  and  terminated  near  the  lower  convex  border  of  the  liver.  Shortly 
before  its  termination,  it  gave  off  towards  the  liver  a bulging  process,  which  exhibited 
some  traces  of  dividing,  but  did  not  nearly  reach  the  margin  of  the  gland  ; a circum- 
stance which  greatly  surprised  me,  as  I had  fully  expected  that  these  offsets  from  the 
intestine  to  the  liver  would  have  proceeded  to  develope  themselves  into  the  hepatic 
duct,  and  not  have  retrograded  as  they  thus  appeared  to  do.  Towards  the  end  of  the 
seventh  day  the  stomach  is  completed  and  overlapped  by  the  two  lobes  of  the  liver; 
the  duodenal  loop  is  also  distinctly  formed ; in  its  concavity  there  is  seen  a curved 
elongated  tract,  which  stretches  up  to  the  hilus  of  the  liver  and  is  there  somewhat 
enlarged  ; it  consists  of  cells,  granular  matter  and  nuclei,  with  an  oily  blastema,  and 
is  clearly  the  rudiment  of  the  pancreas ; as  yet  it  has  no  connection  with  the  intes- 


AND  DEVELOPMENT  OF  THE  LIVER. 


131 


tinal  cavity.  The  liver  consists  almost  wholly  of  nuclei  and  diffused  oily  and  granular 
matter,  without  perfect  cells  ; the  hepatic  vein  is  very  large  and  distinct,  and  arises 
from  a regular  network  of  capillaries  in  the  substance  of  the  organ ; no  trace  of 
hepatic  duct  has  yet  made  its  appearance ; the  primitive  offset  from  the  intestine  is 
still  further  removed  from  the  parenchymatous  mass.  The  prolongations  of  the 
vitelline  duct  (anterior  and  posterior)  have  now  thick  walls,  and  their  cavities  are 
beginning  to  be  formed ; they  are  almost  shut  off  from  the  vitelline  sac,  the  duct  ap- 
pearing only  as  a yellow  streak. 

Near  the  end  of  the  eighth  day  there  was  no  remarkable  change  in  the  pancreatic 
mass  contained  in  the  duodenal  loop ; it  manifestly  had  no  connection  by  ducts  with 
the  intestine,  but  was  truly  a parenchyma.  Close  to  the  liver  on  the  right  of  the 
pancreas  there  were  seen  two  tubes ; the  left  one  of  these  could  be  traced  down  for  a 
considerable  way,  but  was  lost  shortly  before  it  arrived  at  the  lower  part  of  the  pan- 
creas ; it  consisted  of  a distinct  but  very  fine  homogeneous  tunic  enclosing  delicate 
cells  which  formed  a kind  of  epithelium.  The  other  tube  was  distinct  only  near  the 
liver,  where  it  expanded  into  a pyriform  sac  (the  gall-bladder),  the  cavity  of  which 
was  distinct,  lined  by  cells  and  invested  by  an  homogeneous  tunic  ; from  this  dilata- 
tion the  rudiment  of  the  cystic  duct  extended  only  a very  little  way  towards  the  intes- 
tinal cavity.  Near  the  termination  of  the  ascending  portion  of  the  duodenal  loop, 
at  the  part  where  the  remains  of  the  original  offset  were  still  perceptible,  the  wall  of 
the  intestine  was  deficient,  and  there  existed  a semitransparent  space  leading  to  the 
opake  contents  in  the  interior ; but  this  was  soon  lost,  and  did  not  extend  upwards  to 
the  ducts  near  the  liver.  At  the  beginning  of  the  ninth  day  the  gall-bladder  was 
completely  formed,  and  presented  a very  distinct  cavity ; its  duct  ran  down  and  com- 
municated with  the  intestine ; in  the  upper  part  of  its  course  it  was  extremely 
distinct,  being  provided  with  an  homogeneous  tunic,  and  containing  an  abundant 
epithelium ; towards  its  lower  part  its  structure  is  less  distinct,  but  its  course  was 
clearly  indicated  by  a transparent  space,  continuous  with  its  canal,  and  extending 
through  the  intestinal  wall.  The  hepatic  duct  lay  by  its  side ; it  also  was  more  deve- 
loped above  than  below,  and  indeed  could  not  be  followed  quite  into  the  intestine 
though  its  future  course  was  quite  clear ; at  its  upper  part  it  ran  up  to  the  liver,  and 
seemed  just  to  penetrate  it,  but  how  it  terminated  in  this  direction  could  not  be  de- 
termined ; its  diameter  was  nearly  uniform  throughout,  about  s^th  of  an  inch. 
Both  cystic  and  hepatic  ducts  were  clearly  seen  to  join  the  intestine  at  the  part 
where  the  primitive  offset  from  the  anterior  prolongation  of  the  vitelline  duct  existed ; 
this  was  still  represented  by  an  accumulation  of  opake  oily  matter  at  the  spot,  but 
there  was  no  bulging  of  the  intestinal  wall.  The  liver  consisted  of  nuclei,  granular 
and  oily  matter,  and  perfect  cells  ; throughout  its  parenchyma  there  were  many  bright 
yellow  particles  of  bile. 

By  the  first  hour  of  the  tenth  day,  the  ducts  of  the  gall-bladder  and  liver  were 
perfectly  formed,  and  communicated  with  the  intestine  at  the  exact  spot  where  an 

s 2 


132 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


opake  mass  still  indicated  the  situation  of  the  original  offset  from  the  intestine ; the 
gall-bladder  was  quite  visible  to  the  naked  eye,  full  of  green  bile,  which  was  made,  I 
think,  by  pressure  to  flow  into  the  intestine.  The  pancreatic  mass  had  now  sepa- 
rated into  two  portions,  skirting  the  contiguous  margins  of  the  duodenal  loop  ; a 
rudiment  also  of  its  duct  had  begun  to  be  developed  ; it  appeared  as  a solid  cylin- 
drical tract  of  nuclei,  continuous  with,  a canal  which  entered  the  intestine  together 
with  the  ducts  from  the  liver.  By  the  end  of  this  day  two  pancreatic  ducts  were 
distinctly  developed,  one  joining  the  hepatic  just  before  its  termination,  the  other 
entering  the  intestine  together  with  the  hepatic  and  cystic.  I endeavoured  to 
trace  the  further  development  of  the  hepatic  duct  with  its  branches  in  the  substance 
of  the  liver,  but  without  much  success ; it  appeared  to  me  however  that  they  were 
first  formed  as  solid  tracts  of  nuclei,  bearing  some  resemblance  to  the  terminal  ducts 
in  the  mature  condition.  The  parenchyma  of  the  liver  now  contained  numerous  par- 
ticles of  bright  yellow  or  green  bile ; bile  also  filled  the  gall-bladder,  and  had  flowed 
into  the  intestine. 

The  observations  now  related,  warrant  I think,  the  following  conclusions : — 

I.  That  the  liver  exists  at  one  time  as  a parenchymatous  mass,  independent  of  any 
offset  from  the  alimentary  canal. 

II.  That  though  the  first  indications  of  the  hepatic  duct  proceed  from  the  intes- 
tine, yet  these  disappear,  and  are  replaced  by  a separate  and  independent  formation, 
which  gradually  developes  itself  further,  both  downwards  tojoin  the  intestinal  canal, 
and  in  the  substance  of  the  liver  itself. 

III.  Biliary  matter  is  formed  in  the  hepatic  parenchyma  before  its  communication 
with  the  duodenum  is  freely  established. 

The  following  propositions  may  serve  as  a resume  of  the  principal  conclusions  to 
which  we  have  been  led  during  our  survey  of  the  various  forms  of  hepatic  structure. 

The  liver  in  all  vertebrate  animals  may  be  regarded  as  consisting  of  a secreting 
parenchyma  and  excretory  ducts. 

The  size  of  the  excretory  apparatus  bears  only  a small  proportion  to  that  of  the 
secretory. 

These  two  portions  of  the  liver  are  not  continuous  with  each  other,  but  disposed 
simply  in  a relation  of  juxtaposition. 

The  action  of  the  liver  seems  to  consist  in  the  transmission  of  the  bile  as  it  is 
formed  from  cell  to  cell,  till  it  arrives  in  the  neighbourhood  of  the  excretory  ducts 
by  which  it  is  absorbed.  This  action  is  probably  slow,  and  very  liable  to  be  inter- 
fered with,  contrasting  remarkably  with  that  of  the  kidney,  where  a particular  appa- 
ratus is  added  to  ensure  completeness  and  rapidity  of  action. 

The  secretion  of  the  hepatic  cells  is  very  liable  to  be  retained  within  the  gland, 
either  in  the  cells  or  in  a free  state. 

This  circumstance,  as  well  as  its  structural  peculiarities,  seem  to  point  out  the  liver 
as  approximating  to  the  class  of  ductless  glands. 


AND  DEVELOPMENT  OF  THE  LIVER. 


ms 


For  the  same  reason  it  seems  highly  probable,  that  a part  of  the  secretion  of  the 
cells  IS  directly  absorbed  into  the  blood  which  traverses  the  lobules. 

In  a classification  of  the  true  glands  the  liver  seems  to  occupy  the  lowest  position 
the  highest  being  assigned  to  the  permanently  tubular,  such  as  the  kidney  and  testis! 

From  the  condition  of  the  secreting  parenchyma  in  many  instances,  we  learn  that 
the  sem-etory  process  by  no  means  requires  the  formation  of  perfect  cells  in  order  to 

effect  Its  peculiar  changes ; these  may  certainly  occur  in  blastematous  matter  if  a 
nucleus  only  be  present. 

The  condition  of  the  liver  is  in  great  measure  dependent  on  the  intensity  of  the 
respiratory  process;  its  products  being  unused  accumulate  in  the  gland,  often  to  a 
remarkable  extent ; its  function  is  therefore  not  only  vicarious  of  respiration,  as 
formerly  supposed,  but  preparatory,  and  to  some  extent  subsidiary. 

In  concluding  these  inquiries,  I cannot  but  acknowledge  the  kind  assistance  I have 
received  from  my  friend  Mr.  P.  Hewett,  and  also  from  Mr.  H.  Gray,  who  has 

several  times  aided  me  with  his  acute  observation  when  a doubtful  point’ was  to  be 
decided. 


Appendix. 

An  objection  may  be  urged  against  the  account  which  I have  given  of  the  relation 
of  the  ultimate  ducts  to  the  ceils  of  the  liver,  to  the  effect  that  they  are  in  contact 
with  these  particles  to  so  small  an  extent,  that  it  is  difficult  to  understand  how  the 
bile  which  they  secrete  should  be  received  into  the  efferent  ducts. 

In  answer  to  this  I observe,  first,  that  I believe  much  of  the  sreretion  of  the  cells 
IS  directly  absorbed  into  the  blood  traversing  the  lobules. 

Second,  that  I think  it  is  by  no  means  proved  that  the  secretion  of  the  cells  is  per- 
fectly  formed  bile , in  many  instances  it  clearly  is  not : thus,  in  most  fishes  and  in 
the  fatty  hver  of  the  human  subject,  it  is  evident  that  the  gorged  parenchyma  is  full, 
not  of  bilious,  but  of  oily  matter,  out  of  which  however  healthy  bile  is  elaborated  I 

healthy,  without  finding  any  evidence  of  the  presence  of  bile  in  their  contents,  though 
m congested  livers  the  yellow  molecules  are  often  very  distinct  in  the  interior  of  the 

nm*  th  Tl  **  appear  as  pale  granular  bodies,  and  do 

I’c  7 “““  addition  of 

hi,  no  hT  T a ® “ good  deal  of  oily  matter  in  the  cells, 

ut  no  biliary.  I do  not  of  course  deny  that  bile  is  often  formed  in  the  cells  esne 

cially  in  states  of  congestion,  but  I conceive  that  in  the  perfectly  healthy  state  the 
Zs^nhedTcrs*'”  terrainalpor- 


54  Sloane  Street. 


134 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


Explanation  of  the  Plates. 

PLATE  IX. 

Figs.  1,  2,  3,  4 represent  cells  from  the  liver  of  the  Earthworm  ; (1)  and  (2)  are  elon- 
gated and  filled  with  spherules  of  biliary  matter ; the  envelope  is  prolonged 
into  a tubular  neck  in  (1.),  diameter  about  xs^ooth  of  an  inch.  (3.)  has  a 
delicate  envelope,  a nucleus,  and  some  biliary  contents,  diameter  e-g-gth  of 
an  inch.  (4.)  has  a distinct  envelope  enclosing  only  pale  granular  matter, 
diameter  of  an  inch. 

Fig.  5 is  an  ideal  section  of  an  Earthworm,  showing  the  relation  of  the  typhlosole  to 
the  cavity  of  the  intestine.  The  hepatic  stratum  on  the  exterior  of  the  in- 
testine is  seen  to  be  continuous  with  that  in  the  typhlosole ; i is  the  intes- 
tinal cavity  ; f,  that  of  the  typhlosole ; d,  the  dorsal  vessel  in  contact  with 
/,  /,  /,  the  hepatic  stratum. 

Figs.  6,  7,  8,  9,  10  are  taken  from  examination  of  the  liver  in  the  Leech.  (6)  repre- 
sents two  cells  full  of  dark  biliary  contents  cohering  together.  (7)  a cell  con- 
taining pale  amorphous  matter  in  which  some  biliary  spherules  have  begun 
to  appear,  diameter  of  inch.  (8)  is  a cell  containing  only  pale  gra- 
nular matter,  no  perceptible  nucleus,  diameter  e^th  of  an  inch.  (9)  is  a cell 
apparently  dissolving  ; it  has  no  envelope,  and  the  biliary  spherules  are 
separating  from  each  other,  diameter  — of  an  inch : in  the  centre 
there  is  a clear  cavity  which  was  observed  in  many  others,  as  if  the  minute 
spherules  were  repelled  outwards  by  some  force.  (10)  a tube  with  several 
irregular  bulgings,  indicating  the  coalescence  of  the  component  cells  ; one 
cell  is  seen  lying  close  by  the  side  of  the  tube,  but  not  yet  united  to  it : the 
envelope  of  this  tube  was  very  faint  in  most  parts  ; it  almost  resembled  a 
solid  tract  of  biliary  matter. 

Fig.  1 1 . An  hepatic  tubule  from  the  Blowfly  {Musca  vomltorid)  ; it  seems  to  be  made 
up  of  a series  of  vesicles  which  overlie  each  other:  the  outlines  of  all  are 
extremely  distinct,  and  they  all  communicate  together,  being  traversed  by 
a central  canal.  It  is  not  certain  whether  the  first  vesicle  be  truly  the 
origin  of  the  tube,  or  whether  it  has  been  detached  from  others  with  which 
it  was  in  connection  ; there  can,  however,  be  no  doubt  that  the  specimen 
represents  a tube  very  near,  if  not  quite  at  its  origin.  The  basement  tissue 
of  the  tube  was  very  conspicuous ; it  enclosed  a great  quantity  of  yellowish 
granular  matter,  in  which  were  imbedded  some  transparent  cells.  In  some 
parts  of  the  central  canal  there  were  patches  of  opake  oily  matter ; the  dia- 
meter of  the  tube  at  its  origin  was  of  an  inch  ; near  its  lower  part 

y^rd  of  an  inch. 

Fig.  12.  Portion  of  hepatic  tube  from  large  white  Moth  ; its  diameter  is  ^o^h  of  an 


i 


Ihl.  Tr^.'mZCCmi.FLdeM.p.is^. 


J Sasire.hth, 


TMl.TransMfmmj^FLabe  Xp.  i3^. 


JS 


J7  78 


19 


€ 


& 


J.  IB a,fijre,7yith' 


AND  DEVELOPMENT  OF  THE  LIVER. 


135 


inch.  It  consists  of  an  investing  basement  membrane,  which  is  strongly 
marked;  this  supports  a layer  of  pale  granular  matter,  in  which  are  im- 
bedded several  small  transparent  cells  : the  cavity  of  the  tube  is  wide,  and 
is  occupied  by  numerous  very  delicate  transparent  cells,  in  the  interstices  of 
which  are  dark  clusters  of  biliary  granules.  At  a,  two  of  the  transparent 
cells  are  shown  which  had  escaped  from  the  tube  ; they  are  perfectly  glo- 
bular and  contain  only  a limpid  fluid  ; they  are,  I think,  of  constant  occur- 
rence in  the  hepatic  tubes  of  insects. 

Fig.  13.  View  of  parenchymatous  portion  of  the  Blowfly’s  liver  (or  adipose  tissue)  in 
early  stage  of  its  formation.  Several  nucleated  cells,  diameter  y^o^h  of  an 
inch,  containing  granular  matter,  are  seen  lying  in  a pale  granular  blastema, 
along  with  several  large  oil* globules  ; a vesicle  and  tube  are  in  process  of 
formation  from  the  blastema : these  will  include  one  or  more  nucleated  cells. 
{a)  is  a nucleated  cell  from  the  blastema,  diameter  -^^Q-oth  of  an  inch,  probably 
an  early  condition  of  the  larger  cells ; {b)  a fully-formed  vesicle,  diameter 
yy-and  of  an  inch,  containing  yellowish  granular  matter,  and  a nucleated 
cell. 

Fig.  14.  An  elongated  vesicle,  -^th  of  an  inch  long,  xTr^h  of  an  inch  wide  at  its 
middle,  formed  of  an  homogeneous  membrane,  enclosing  dark  oily  con- 
tents ; it  is  traversed  in  its  whole  length  by  a minute  tracheary  tube,  which 
having  become  very  fine  issues  from  it  at  its  upper  extremity.  (From  brown 
Moth.) 

PLATE  X. 

Figs.  15,  16,  17  from  liver  of  Tench  ; they  represent  minute  biliary  ducts  isolated 
from  the  parenchyma.  (15)  exhibits  a delicate  homogeneous  tubular  mem- 
brane, in  the  interior  of  which  are  several  large  delicate  epithelial  cells  ; the 
last  of  these  lay  so  close  to  the  extremity  of  the  specimen,  that  it  could 
not  be  determined  whether  the  homogeneous  membrane  formed  an  actual 
csecal  termination;  diameter  -yoVoth  of  an  inch.  (16)  exhibits  at  its  lower 
part  the  tubular  character  ; towards  its  termination  this  is  lost : it  has  the 
appearance  of  a tract  of  granular  matter  with  even  borders  ; several  nuclei 
can  be  discerned  in  it ; diameter  of  an  inch.  (17)  is  a duct,  y^th  of 

an  inch  diameter,  consisting  of  nuclear  granules  and  granular  matter ; its 
extremity  is  quite  even,  though  it  is  difficult  to  determine  whether  it  is 
completely  invested  by  homogeneous  membrane. 

Fig.  18.  A minute  duct,  probably  terminal,  from  liver  of  Perch;  its  diameter  is 
so^ooth  of  an  inch  : it  consists  of  distinct  nuclei,  set  as  it  were  in  a faintly 
mottled  basis-substance. 

Fig.  19.  A group  of  peculiar  cells  from  the  parenchyma  of  liver  of  Mackerel ; their 
diameter  varies  from  x^o“o  to  of  an  inch.  They  have  a well-marked 


136 


DR.  C.  H.  JONES  ON  THE  STRUCTURE 


Fig-.  20. 


Fig.  21. 


Fig.  22. 


Fig.  23. 


Fig.  24. 


Fig.  25. 


envelope,  and  contain  3-5  circular  or  oval  vesicles,  which  have  somewhat 
the  aspect  of  nuclei : the  whole  group  of  cells  are  imbedded  in  a collection 
of  yellow  granules  of  rather  large  size. 

One  of  the  vesicles  occurring  in  the  parenchyma  of  the  Skate’s  liver.  The 
central  cavity  is  shown  with  traces  of  surrounding  laminae  concentric  to 
the  envelope,  between  which  are  some  small  vesicles  : long  diameter  about 
3^th  of  an  inch  ; short  4^th  of  an  inch. 

A rather  large  branch  of  the  hepatic  duct,  diameter  y^th  of  an  inch  ; its 
walls  consist  of  homogeneous  membrane  with  investing  fibrous  tissue ; its 
cavity  is  filled  with  nuclear  granules,  finely  granular  matter  and  oil-globules ; 
from  its  side  there  springs  off  a minute  branch,  which  tapers  evenly  to  its 
termination  ; its  diameter  is  xsVofh  of  an  inch  ; near  its  origin  it  has  a di- 
stinct homogeneous  tunic  and  a little  fibrous  investment ; towards  its  ex- 
tremity the  homogeneous  membrane  can  no  longer  be  discerned,  though  the 
margins  are  even  and  the  extremity  rounded,  and  there  is  not  the  slightest 
appearance  of  its  having  suffered  injury ; it  is  I believe  really  a terminal 
branch  becoming  resolved,  as  many  others  are  seen  to  be,  into  a delicate 
tract  of  granular  matter ; in  some  of  these,  as  in  fig.  16,  nuclei  are  manifestly 
to  be  found ; in  others  they  are  scarcely  perceptible,  or  apparently  absent. 
(From  Flounder.) 

A large  branch  of  the  hepatic  duct  with  several  minute  offsets  ; some  of  these, 
as  well  as  the  main  branch,  have  pretty  large  yellow  masses  of  biliary  matter 
adhering  to  their  exterior.  The  interior  is  filled  with  nuclear  granules  and 
granular  matter.  (From  Tench.) 

A small,  probably  terminal,  duct  from  liver  of  Grass  Snake ; it  tapers  from 
'a  oVo^h  to  3-^g^th  of  an  inch  ; its  extremity  is  rounded  ; no  basement  mem- 
brane can  be  discerned  ; it  seems  to  consist  of  nuclei  set  in  a finely  mottled 
substance. 

A branch  of  the  hepatic  duct,  with  a minute  lateral  offset  from  liver  of  Duck. 
The  parent  branch  has  an  homogeneous  tunic  with  fibrous  investment ; on 
its  interior  there  is  a granular  epithelial  layer,  in  which  nuclei  are  but  faintly 
discernible ; the  offset  is  Y^th  of  an  inch  in  length,  and  of  an  inch 

wide  near  its  termination  ; it  gives  off  no  branches  ; in  the  greater  part  of 
its  extent  it  has  a tunic  of  basement  membrane  enclosing  nuclei  dispersed 
through  granular  matter;  its  terminal  extremity  was  somewhat  obscured, 
being  in  contact  with  some  remains  of  parenchyma,  but  I am  inclined  to 
think  it  was  closed ; another  specimen  from  the  same  was  distinctly  seen 
to  terminate  by  a closed  extremity. 

A minute  duct  from  liver  of  Sheep  perfectly  isolated  from  other  structures ; 
its  diameter  is  jQ^ooth  of  an  inch,  its  length  of  an  inch  ; it  gives  off 

no  branches ; its  extremity  appears  to  be  closed ; it  has  perfectly  defined 


mi,  Trai,.s,mzc.CmiIUjiJbMr(i.  lU. 


AND  DEVELOPMENT  OF  THE  LIVER. 


137 


margins,  but  no  basement  membrane  can  be  detected  by  the  most  careful 
scrutiny  ; it  consists  of  nuclei  set  in  a partly  granular,  partly  amorphous 
basis-substance  ; it  issues  from  a quantity  of  fibrous  tissue,  which  is  seen  at 
the  upper  part. 

Fig.  26.  View  of  a terminal  duct  from  liver  of  Sheep  lying  in  an  interlobular  fissure ; 

it  commences  in  a “ space,”  and  is  seen  clearly  not  to  give  off  any  branches 
in  its  whole  extent,  as  it  runs  along  the  fissure;  its  extremity,  I am  nearly 
sure,  was  closed,  though  it  was  rather  obscured  by  the  investing  membrane, 
under  which  it  dipped  as  it  approached  the  side  of  the  lobule ; the  length 
of  this  duct  was  ^th  of  an  inch  ; its  diameter,  -g^th  of  an  inch,  was  nearly 
uniform  throughout ; its  walls  were  formed  by  nuclei  of  great  distinctness, 
set  close  together  in  an  amorphous  basis-substance  ; no  basement  membrane 
could  be  positively  said  to  exist ; the  hepatic  duct  had  been  injected,  and  a 
small  mass  of  the  colouring  material  was  seen  occupying  the  cavity  of  the 
minute  duct  where  it  lay  in  the  interlobular  “ space.” 

Fig.  27.  A minute  duct,  diameter  of  an  inch,  from  Human  liver;  it  lies  in  a 

tract  of  fibrous  tissue,  from  which  however  it  is  quite  distinct ; on  its  right 
margin  there  seems  to  be  a delicate  homogeneous  membrane,  but  it  ceases 
before  the  extremity  ; this  is  perfectly  even,  and  evidently  has  not  suffered 
injury;  the  duct  chiefly  consists  of  nuclei  set  in  a subgranular  basis-sub- 
stance. 

PLATE  XI. 

Fig.  28.  A biliary  duct  from  liver  of  Bullock  with  a lateral  terminal  branch ; the 
walls  chiefly  consist  of  nuclei  and  granular  matter,  and  are  not  invested  by 
a distinct  basement  membrane  except  at  a ; the  margin  however  is  quite 
even  ; diameter  of  terminal  extremity  g^th  of  an  inch. 

Fig.  29.  Terminal  duct  from  Human  liver,  diameter  i>^ch  ; it  is  not  in- 

vested by  basement  membrane,  but  consists  of  nuclei  set  in  a faintly  gra- 
nular basis-substance ; at  its  extremity  it  lies  in  contact  with  a group  of 
hepatic  cells. 

Fig.  30.  View  of  oesophagus,  stomach,  liver  and  intestine  of  Chick  towards  end  of 
6th  day  of  incubation.  CEs.  oesophagus.  S.  stomach.  L.  liver ; its  two  lobes 
are  represented.  V.  sac.  Vitelline  sac.  V.  duct.  Vitelline  duct.  A.  anterior 
prolongation  of  vitelline  duct.  P.  posterior  prolongation  of  vitelline  duct. 
H.  offset  to  liver,  primitive  rudiment  of  hepatic  duct. 


MDCCCXLIX. 


T 


[ 139  ] 


X.  Minute  structure  of  the  Papillce  and  Nerves  of  the  Tongue  of  the  Frog  and  Toad. 
By  Augustus  Waller,  M.D.  Communicated  hy  Richard  Owen,  Esq.^  F.R.S.,  8^c. 


Received  Feb.  26, — Read  April  13,  1848. 

The  attention  of  physiologists  was  first  directed  by  me  to  the  peculiar  advantages 
possessed  by  the  tongue  of  the  living  frog  and  other  similar  animals  for  micro- 
scopic investigation,  in  the  year  1839.  The  extreme  elasticity  and  transparency  of 
this  organ  induced  me  to  submit  it  to  the  microscope,  principally  with  a view  of 
examining  the  muscles  during  contraction.  I communicated  these  experiments  to 
M.  Donne,  who  has  mentioned  my  claim  of  priority  in  his  Cours  de  Microscopic, 
p.  108,  and  they  were  first  made  public  at  the  Societe  Philomatique,  Aug.  17,  1839*. 
It  will  be  unnecessary  in  a communication  addressed  to  the  Royal  Society,  to  occupy 
the  time  of  that  learned  body  by  recapitulating  what  is  already  known  respecting  the 
organ  of  taste.  I shall  therefore  proceed  at  once  to  describe  the  results  of  my  further 
researches  on  this  organ,  by  which  I have  been  enabled  to  determine  the  peculiar 
structure  of  the  papillae,  and  the  ultimate  termination  of  the  nerves  within  them. 
In  conclusion,  I will  point  out  the  deductions  which  necessarily  ensue  with  regard 
to  the  distinct  nature  of  the  functions  of  these  organs  in  the  act  of  taste. 

Tongue  of  the  Frog. 

In  this  we  find  the  same  component  parts  as  in  the  tongue  of  man.  The  principal 
points  of  difference  are  its  smaller  size,  and  the  manner  in  which  it  is  placed  in  the 
mouth.  In  other  respects  it  presents  the  greatest  analogy  with  that  of  the  human 
subject.  Its  frame-work  is  composed  of  two  muscles,  the  hyoglossus  and  the  genio- 
glossus.  The  hyoglossus  arises  from  the  inferior  border  of  the  body  of  hyoid  bone 
and  ascends  to  its  superior  border,  the  fibres  diverging ; afterwards  it  reflects  back- 
wards in  the  throat,  the  fibres  forming  a fan-like  expansion.  The  genioglossus  is  a 
small,  thick,  triangular  muscle,  inserted  by  its  base  to  the  centre  of  the  lower  maxil- 
lary. The  summit  terminates  near  the  inner  third  of  the  tongue  in  a tendinous  ex- 
tremity. These  two  muscles  unite  at  an  acute  angle,  and  when  at  rest  hang  down 
the  throat.  The  form  of  the  tongue  differs  from  that  of  other  animals.  The  anterior 
extremity  is  broad,  with  a notch  which  divides  it  into  two  extremities  or  tubercles. 
The  precise  form  of  the  extremity  is  best  seen  when  compressed  between  two  slips  of 
glass.  In  a state  of  rest  the  extremity  of  the  tongue  hangs  down  the  throat,  where 
it  serves  as  a valve  to  close  the  posterior  nares  in  the  act  of  swallowing  the  air  for 

* Minutes  of  which  are  to  be  seen  in  the  Journal  de  I’lnstitut,  p.  316,  year  1839. 

T 2 


140 


DR.  A.  WALLER  ON  THE  MINUTE  STRUCTURE  OF  THE  PAPILLA 


respiration.  It  likewise  acts  as  an  agent  for  seizing  prey  by  being  rapidly  thrown 
out  of  the  mouth,  and  enveloping  the  object  to  be  laid  hold  of.  In  this  act  it  is  pro- 
truded from  the  mouth  by  turning  round  the  lower  jaw  bone  as  a centre  of  rotation, 
the  upper  surface  then  becoming  lowermost.  The  lingual  arteries  and  veins  are 
derived  from  the  same  trunks  as  in  man,  ascend  the  throat  parallel  to  each  other, 
and  enter  the  tongue  between  the  hyoglossus  and  the  genioglossus.  The  nerves  con- 
sist of  two  pairs,  one  direct  from  the  brain,  the  other  from  the  spinal  marrow. 

Mode  of  'preparing  the  Frog's  Tongue  for  examination. 

In  former  experiments  I confined  the  animal  in  a narrow  bandage,  which  I rolled 
round  it  from  the  feet  to  the  neck.  In  this  state  all  movement  of  the  limbs  was  com- 
pletely prevented,  while  it  was  still  able  to  carry  on  respiration.  A piece  of  sheet 
cork,  about  the  breadth  and  length  of  the  animal,  was  then  provided,  and  an  open- 
ing made  near  one  end  of  about  the  size  of  a shilling.  After  being  secured  to  this 
cork,  the  tongue  was  turned  out  of  the  mouth  and  stretched  over  the  opening  by 
means  of  pins.  But  notwithstanding  every  care  that  could  be  taken  it  frequently 
happened  that  the  experiment  would  be  interrupted  by  the  movement  of  the  tongue, 
and  its  being  torn  from  the  pins.  I am  now  able,  by  submitting  the  animal  to  the 
action  of  ether,  to  avoid  these  objections.  For  this  purpose  I find  it  most  convenient 
to  place  the  frog  in  a large  wide-mouthed  bottle,  closed  with  a ground  stopper,  and 
containing  ether.  To  prevent  the  contact  of  the  ether  with  the  animal’s  body, 
where  it  would  produce  inflammation,  I keep  the  ether  apart  in  a small  phial,  which 
is  introduced  into  the  bottle,  so  that  in  all  the  animal’s  movements  it  never  is  affected 
by  the  liquid.  Placed  in  this  kind  of  closed  chamber,  the  frog  becomes  quickly 
narcotized  by  the  ethereal  atmosphere.  The  cessation  of  all  motion  shows  the  period 
when  insensibility  has  taken  place,  and  it  may  be  withdrawn  and  the  tongue  ex- 
panded around  the  opening  as  before  described.  Usually  the  animals  are  completely 
insensible  after  about  five  minutes’  exposure,  and  remain  in  that  condition  for  upwards 
of  half  an  hour.  The  insensibility  may  be  prolonged  to  several  hours  by  leaving 
them  longer  in  the  bottle.  An  exposure  of  half  an  hour  generally  renders  them  in- 
sensible for  two  hours.  In  this  way  we  have  the  great  advantage  of  avoiding  all 
pain  to  the  animal,  independently  of  rendering  the  experiment  more  easy.  I find 
the  action  of  ether  perfectly  harmless  to  life,  not  having  observed  a single  death  in 
consequence  of  its  action,  even  where  it  had  been  prolonged  for  several  hours.  A 
curious  anomaly  exists  with  regard  to  the  full-grown  female  frogs ; for  I find  in  my 
experiments  this  winter  that  they  are  brought  under  its  influence  with  much  greater 
difficulty  than  the  males  and  smaller  animals,  so  much  so,  that  after  two  hours’  expo- 
sure they  are  less  influenced  than  one  of  the  latter  after  five  minutes.  The  advan- 
tages of  ether  are  so  great  that  I have  abandoned  my  former  method,  to  which  I shall 
only  recur  when  I have  to  describe  the  difference  in  microscopic  appearances  in 
animals  that  have  been  etherized  from  those  which  have  not. 


AND  NERVES  OF  THE  TONGUE  OF  THE  FROG  AND  TOAD. 


141 


Instead  of  sulphuric  ether  we  may  employ  chloroform,  muriatic  ether,  nitric  ether, 
camphor,  sulphuret  of  carbon,  naphtha,  alcohol,  and  various  other  volatile  bodies. 
In  some  cases  it  will  be  found  more  advantageous  to  examine  only  a small  portion 
of  the  tongue,  which  may  be  done  by  removing  a small  piece  of  the  membrane  with 
scissors,  and  interposing  it  between  two  slips  of  glass  ; this  applies  more  particularly 
to  those  animals  whose  tongues  are  opake  and  not  elastic. 

Burdach  has  mentioned  another  method  of  examining  the  dead  tongue  by  dipping 
it  into  a dilute  solution  of  caustic  potash,  and  then  interposing  it  between  the  plates 
of  the  compressorium.  As  an  auxiliary  means,  I may  mention  that  by  the  application 
of  a dilute  solution  of  potash  (about  twenty  parts  water  to  one  of  liquor  potassse)  we 
may  also  render  the  living  tongue  much  more  transparent.  Another  means  of 
preparation  is  to  keep  the  animal  for  several  days  after  death,  when  the  maceration 
of  the  organ  in  its  own  moisture,  and  the  partial  state  of  putrefaction,  cause  the  de- 
tachment of  the  epithelial  scales  and  the  uncovering  of  the  subjacent  parts.  Each 
of  these  means  will  be  found  to  have,  in  certain  cases,  its  peculiar  advantage,  and  we 
cannot  vary  and  multiply  them  too  much,  as  in  each  case  we  view  nature  under  a 
different  aspect.  As  I have  described  on  a former  occasion*  the  principal  phenomena 
connected  with  circulation  in  this  organ,  I will  examine  now  those  parts  of  the  tongue 
which  have  reference  to  its  sensorial  functions  of  taste  and  of  touch.  The  nerves  which 
possess  these  powers  are  distributed  and  supported  by  the  tegumentary  membranes 
of  the  two  sides  of  the  tongue,  our  attention  will  therefore  be  directed  to  the  various 
tissues  of  which  these  two  membranes  consist. 

Vlbratile  Cilia  and  Rugae. — The  first  parts  which  engage  our  attention,  exclu- 
sively of  the  mucus  on  the  surface,  are  the  vibratile  cilia  of  the  tongue.  The  most 
active  ciliary  movement  exists  at  the  borders  of  the  tongue.  When  a minute  por- 
tion of  the  membrane  is  removed,  anywhere  near  the  edges  and  anterior  extremity, 
we  generally  observe  a most  active  movement  at  the  borders  of  the  fragment,  and 
over  its  surface  we  find  numerous  channels  running  obliquely  outwards  and  forwards, 
evidently  corresponding  to  those  rugae  we  meet  with  on  the  human  tongue  in  a 
similar  situation.  The  ciliary  filaments  seen  down  these  furrows  meet  at  an  obtuse 
angle,  and  exhibit  a constant  undulating  movement  transmitted  downwards  from  one 
extremity  to  the  other.  Any  small  body  coming  into  this  channel  is  generally  pro- 
pelled quickly  in  one  direction.  Occasionally  a succession  of  blood-particles  are 
seen  running  down  this  channel  which  might  easily  be  mistaken  for  blood  circulating 
within  a capillary.  The  appearance  of  the  blood-particles  viewed  with  a power  of 
400  diameters  while  beaten  about  by  the  ciliary  filaments  is  sometimes  very  curious. 
The  form  of  the  vesicle  is  seen  to  vary  in  the  most  singular  manner,  sometimes 
dilated,  sometimes  compressed  longitudinally  or  transversely,  like  a bladder  partly 
filled  with  water  when  beaten  about  with  rods.  When  the  fragment  has  been  freshly 
divided,  a general  tremor  is  observed  at  first,  which  arises  from  the  irritation  of  the 

* Phil.  Mag.  vol.  xxix. 


142 


DR.  A.  WALLER  ON  THE  MINUTE  STRUCTURE  OF  THE  PAPILLA 


divided  muscular  fibres,  and  which  ceases  after  a short  time.  The  ciliary  action,  on 
the  contrary,  lasts  a considerable  time,  and  I have  detected  it  two  days  after  death 
in  some  instances.  Even  in  a small  detached  fragment  placed  under  the  microscope 
I have  known  it  to  last  for  several  hours,  and  it  would  probably  continue  still  longer 
if  kept  moistened  with  saliva.  After  remaining  about  half  an  hour  under  examination 
the  border  of  the  tongue  is  seen  to  undergo  an  alteration.  Tiie  particles  of  epithelium 
become  uneven  and  gradually  disaggregated.  These  entirely  separate  at  some  spots, 
and  consequently  numerous  small,  uneven  cavities  are  formed  along  the  borders. 
The  surface  of  the  fungiform  papillae  is  covered  with  cilia  in  active  motion,  while  the 
conical  papillae  by  the  side  of  them  are  entirely  devoid  of  them. 

The  Conical  Papillce  over  the  expanded  tongue  are  found  of  various  forms, 
conical  or  cylindrical ; sometimes  simple,  sometimes  compound,  like  so  many  conical 
projections  seated  on  one  body.  We  generally  succeed  in  detecting  an  opening  at 
the  summit  of  each  of  them.  The  opening  is  either  sharp  at  the  edges  or  anal- like 
with  circular  lips.  From  above  we  see  the  commencement  of  a cavity  lined  with 
epithelium,  which  I have  been  able  to  see  terminate  in  an  infundibular  canal  extending 
towards  the  base  of  the  papilla.  These  papillae  generally  contain  no  vascular  capil- 
laries within  them.  When  they  do  exist,  they  never  ascend  to  the  summit  of  the  body, 
but  form  a bend  or  loop  at  about  the  half  or  lower  third  of  the  height  of  the  cone. 

Fungiform  Papillce. — These  are  easily  distinguished  from  any  other  bodies  on  the 
surface  of  the  tongue,  by  the  existence  within  them  of  a coil  of  capillary  vessels 
generally  containing  blood  in  a state  of  active  circulation.  They  are  always  larger 
and  redder  than  the  conical  papillae ; sometimes  they  present  at  the  summit  a red 
point  of  apparently  extravasated  blood,  but  which,  when  examined  under  a high 
power,  is  found  to  be  merely  an  engorged  vessel.  A similar  appearance  on  a larger 
scale  is  often  seen  on  the  fungiform  papillae  in  man.  The  fungiform  papillae  consist 
of  a circular  zone  of  epithelian  cells  containing  a central  area  filled  with  coils  of 
capillary  vessels,  and  with  nerve-tubules  ascending  and  terminating  abruptly  amongst 
them.  When  examined  on  an  expanded  tongue,  we  can  form  no  accurate  idea  of 
the  real  elevation  of  these  bodies,  as  they  appear  like  discs  adhering  to  the  mem- 
brane subjacent,  the  stem  not  being  visible ; but  if  we  remove  a small  fragment  of 
the  membrane  and  interpose  it  between  glass,  we  find  them  standing  out  in  relief  at 
the  borders,  and  of  the  same  form  as  in  other  animals,  viz.  that  of  a flask  or  gourd. 
Some  have  a long  pedicel,  which  becomes  gradually  narrower  to  its  point  of  inser- 
tion to  the  membrane,  where  its  thickness  scarcely  equals  a fourth  or  fifth  of  that  of 
the  body.  Others  are  with  scarcely  anything  deserving  the  name  of  pedicel ; and 
again  some  are  compound,  consisting  of  either  of  the  above  varieties,  with  the 
addition  of  one  or  two  small  conical  papillae  joined  to  the  external  zone. 

These  varieties  arise  rather  from  their  position  on  the  tongue,  than  from  any  structural 
distinction.  The  degree  of  contraction  of  the  pedicel  and  its  height  are  connected 
with  the  height  and  size  of  the  conical  papillae  around  them.  Where  these  are  long 


AND  NERVES  OF  THE  TONGUE  OF  THE  FROG  AND  TOAD. 


143 


and  thickly  studded,  as  at  the  dorsum  and  base  of  the  tongue,  the  fungiform  are  like- 
wise long  and  generally  contracted.  At  the  borders  and  at  the  tubercles,  where  the 
papillae  conicse  are  short,  the  fungiform  are  thick,  short,  and  surrounded  by  a thick 
protecting  membrane  of  the  same  nature  as  in  the  papillae  conicae,  which  in  the 
lengthened  fungiform  papillae  is  much  less  solid. 

By  the  application  of  a minute  quantity  of  solution  of  potash  over  a fungiform 
papilla,  we  sometimes  observe  a curious  appearance.  The  external  zone  becomes 
separated  from  the  central  area  by  a deep  fissure,  and  forms  a kind  of  cup  contain- 
ing the  blood-vessel,  which  appears  like  a spiral  tube,  and  within  this  is  seen  the 
bundle  of  nerves.  The  circulation  continues  for  some  time  in  the  papillary  vessels 
even  in  this  denuded  state,  then  becomes  languid,  and  finally  ceases  when  coagulation 
of  the  blood  takes  place,  unless  the  vessels  burst  at  some  point  and  extravasation 
of  blood  ensues,  which  is  frequently  the  case,  preventing  any  further  observation. 

The  vessels  of  these  papillae  are  generally  derived  from  arteries  and  veins,  situated 
near  the  inferior  surface  of  the  tongue,  from  whence  they  ascend  in  a vertical 
direction  until  they  reach  the  pedicel  of  the  papilla.  At  this  point  the  arterial  and 
venous  canals  appear  to  be  already  reduced  to  the  size  of  the  ordinary  capillary 
tubes,  and  they  do  not  appear  to  undergo  much,  if  any,  further  decrease  of  size  in 
the  capillary  tuft  at  the  summit.  We  might  at  first  imagine  that  these  coils  are  the 
continuation  of  one  single  tube,  but  such  is  not  the  case.  They  frequently  com- 
municate with  each  other,  for  when  circulation  is  arrested  or  impeded  in  one  loop,  it 
often  continues  in  the  adjacent  ones.  They  contain  no  valves  sueh  as  are  found  at 
other  parts  of  the  tongue,  for  after  any  violent  movement  of  the  tongue  the  circula- 
tion often  changes  its  direction,  and  what  was  at  first  an  arterial  capillary  is  after- 
wards found  to  convey  the  blood  towards  the  heart  like  a vein.  ' 

Besides  blood-vessels  and  nerves,  we  invariably  discover  in  the  interior  of  the  fun- 
giform papillse  numerous  striated  muscular  fibres.  They  are  derived  from  the  super- 
fieial  muscular  layer,  which  exists  beneath  the  basement  membrane  of  the  dorsum 
of  the  tongue,  and  appear  to  be  one  of  the  essential  elements  of  the  mucous  tegument 
of  that  region.  They  run  parallel  with  the  vessels  and  nerves,  to  which  they  are 
external,  and  form  a complete  investment.  After  attaining  nearly  to  the  summit  of 
the  papilla,  they  curve  inwards,  and  afterwards  disappear  in  the  surrounding  tissueSj 
apparently  by  losing  their  striae  and  sarcolemma,  which  are  their  distinctive  charac- 
ters. This  mode  of  termination  of  the  fibres  is  deserving  of  attention,  and  is,  I 
believe,  the  only  instance  in  which  the  gradual  transformation  of  the  muscular  ele- 
ment into  any  other  tissue  than  the  fibrous  variety  composing  tendons  has  been 
discovered.  I have  before  mentioned  the  ciliary  motion  on  the  surface  of  these  pa- 
pillae, and  its  absence  over  the  other  papillae  which  are  destitute  of  muscular  fibres. 
We  are  therefore  led  to  the  conclusion  that  ciliary  and  muscular  power  are  more 
closely  connected  than  is  commonly  imagined.  The  action  of  these  fibres  is  to 
shorten  the  papilla,  probably  at  the  same  time  they  may  compress  the  vessels,  regu- 


144 


DR.  A.  WALLER  ON  THE  MINUTE  STRUCTURE  OF  THE  PAPILLA 


lating  to  some  extent  the  current  of  blood,  and  produce  the  turgescence  of  these  pa- 
pillae which  has  been  observed  in  the  higher  animals.  The  action  of  the  cilia  is  very 
evident  while  under  experiment.  It  conduces  to  clear  away  foreign  bodies  from  the 
surface ; to  equalize  the  distribution  of  the  sapid  substance  over  them,  and  conse- 
quently over  the  nervous  extremities ; and  to  promote  the  removal  of  the  epithelial 
scales  which  are  constantly  being  shed. 

Nerves  of  the  Papilloe  conicoe. — The  epithelial  scales  veil  these  in  general  so  com- 
pletely that  it  is  difficult  to  detect  them.  The  application  of  the  alkali  which 
dissolves  the  seales,  also  disorganizes  the  nerves  beneath.  The  plan  which  I find 
the  most  successful,  is  to  macerate  the  part  for  an  hour  or  two  in  saliva  or  water, 
when  the  increased  transparency  of  the  membrane  renders  the  nerves  more  distinct. 
They  are  generally  single,  rarely  two  or  three  running  together.  Their  course  is 
irregular,  wavy,  with  frequent  simple  loops,  which  enables  them  to  present  a much 
greater  surface.  In  the  tubule  we  frequently  observe  small  granulations,  but  no 
white  substance  of  Schwann  is  detected  when  perfectly  fresh,  although  it  frequently 
appears  after  the  object  has  been  kept  for  some  time  under  examination.  As  a 
general  rule  in  the  conical  papillae,  the  nerve-tube  runs  close  to  the  aperture  of  the 
papilla  around  which  it  forms  loops,  after  which  it  runs  away  in  a wavy  direction. 
Often  at  each  angle  of  the  aperture  is  a nerve-loop  of  this  kind  formed  by  separate 
tubes,  besides  others  which  are  seen  running  in  a meandering  course,  and  crossing 
the  former  in  various  directions.  The  space  enclosed  by  these  nervous  loops  is  much 
darker  than  elsewhere,  as  if  it  contained  some  dark  granular  matter.  The  tubes 
never  appear  to  terminate  abruptly  in  free  extremities.  They  are  derived  from  trunks 
which  give  off  at  nearly  regular  intervals  two  or  three  tubules  closely  joined  together, 
which  afterwards  subdivide  in  a manner  more  and  more  irregular,  till  they  reach  the 
state  of  single  nerve-tubules. 

It  is  evident  that  these  are  the  nerves  which  convey  the  sensations  of  touch  to  the 
brain.  The  situation  which  they  occupy  at  the  base  of  the  conical  papillae  under- 
neath the  epithelian  scales,  can  leave  no  doubt  in  this  respect.  It  is  true,  that  as  at 
the  base  of  the  conical  papillae,  and  immediately  beneath  the  epithelian  scales,  we 
find  striated  muscular  fibres  running  in  various  directions,  and  some  ascending  into 
the  interior  of  the  body  of  the  fungiform  papillae,  it  might  be  surmised  whether  these 
nerves  are  not  destined  to  excite  the  contractile  powers  of  these  fibres.  But  their 
development,  so  utterly  disproportioned  to  the  office  of  stimulating  a few  muscular 
fibres,  their  mode  of  distribution  in  loops  and  convolutions,  and  their  separation  into 
single  or  double  tubules,  prevent  our  regarding  them  as  muscular  nerves.  A curious 
point  in  reference  to  the  nerves  of  touch,  especially  in  the  skin,  are  the  fruitless 
attempts  that  have  been  made  by  numerous  observers,  to  detect  their  ultimate 
terminations  in  the  interior  of  the  papillae.  On  account  of  the  impossibility  of 
seeing  the  nerve-tubules  within  the  papillae,  it  has  been  imagined  by  some  that  they 
lose  their  external  covering,  and  that  they  experience  a gradual  fusion  with  the 


AND  NERVES  OF  THE  TONGUE  OF  THE  FROG  AND  TOAD. 


145 


papillary  structure  which  must  effectually  prevent  our  seeing  them  in  these  tissues. 
In  my  researches  on  the  frog’s  tongue,  I have  never  observed  any  alteration  in  the 
appearance  of  the  tubules  in  support  of  this  hypothesis,  which  1 am  therefore  led  to 
reject.  In  searching  for  the  extremities  of  these  nerves,  which  for  brevity  I will 
term  the  tactile  nerves,  in  opposition  to  the  others  which  are  either  gustatory  or 
muscular,  I experience  considerable  difficulty  in  detecting  them  until  one  or  two 
simple  tubes  are  seen,  which  being  followed  for  some  distance,  serve  as  a clue  to 
numerous  other  convolutions  around  them.  By  this  means  a spot  which  a moment 
before  appeared  covered  with  epithelium  and  destitute  of  nerves,  is  seen  to  be  covered 
with  abundant  nerve-tubes  distributed  in  the  way  I have  mentioned.  If  such  is  the 
case  with  regard  to  the  nearly  transparent  epithelium  and  papillae  of  the  frog,  how 
much  more  so  must  it  be  the  case  in  the  papillae  of  the  skin,  where  observers  have 
hitherto  sought  them,  and  where  they  are  obliged  to  employ  chemical  agents  to  in- 
crease the  transparency  of  this  membrane ! 

To  attain  a view  of  their  terminations,  we  are  obliged  to  flatten  the  papillae  by 
compression.  In  this  state  we  cannot  determine  to  what  height  the  nerves  ascend 
within  them.  I have  repeatedly  in  vain  attempted  to  trace  the  nerve  in  the  conical 
papillae,  seen  in  section  at  the  borders  of  a fragment,  while  at  the  same  time  in  an 
adjacent  fungiform  papilla  I have  obtained  a perfect  sight  of  the  gustatory  nerves. 
The  farthest  points  to  which  I have  followed  them  in  these  circumstances  has  been 
to  their  base,  where  the  capillaries  and  the  muscular  fibres  form  a kind  of  basement 
structure.  Here  the  nerves  are  found  agglomerated  together  in  knots,  wherein  the 
continuity  of  the  tubules  could  not  be  traced.  These  knots  were  probably  of  a gan- 
glionic nature.  Over  the  vessels  nerve-tubules  of  about  one-third  of  the  size  of 
ordinary  nerve-tubes  were  sometimes  seen. 

Nerves  of  the  Fungiform  Papillce. — The  papillary  nerve  may  be  seen  at  some 
distance  before  it  reaches  the  pedicel,  to  form  numerous  waving  incurvations,  which 
appear  to  increase  as  it  approaches  it.  Near  the  pedicel  we  usually  perceive  a kind 
of  knot  which  contains  numerous  loops  of  the  nerve.  Before  it  reaches  this  knot,  it 
is  found  to  be  composed  of  separate  nerve-tubules,  generally  not  more  than  five  or 
six  in  number.  If  not  sufficiently  distinct,  it  may  be  rendered  more  so  by  a drop  of 
alkali  which  dissolves  the  epithelium.  In  following  the  nerve  to  the  pedicel,  we  per- 
ceive that  it  becomes  darker,  its  fibres  more  confused,  and  occasionally  with  vesicular 
granules  interposed  between  the  tubules.  When  the  expanded  tongue  is  seen  with 
a low  power,  the  nervous  knot  at  the  pedicel  is  almost  invariably  detected  by  its 
dark-grey  aspect  and  numerous  loops.  After  forming  this  intricate  arrangement, 
the  nerve-tubules  ascend  into  the  interior  of  the  papillae,  and  expanding,  become  less 
dark.  By  the  use  of  the  compressorium  and  the  alkali  we  are  enabled  to  see  their 
termination  with  ease.  After  nearly  attaining  the  summit  of  the  papillae,  we  find  some 
of  the  tubules  to  separate  from  the  main  body  at  an  acute  angle,  proceeding  until  they 
reach  some  of  the  capillary  vessels,  where  each  tubule  terminates  abruptly,  most 

MDCCCXLIX.  u 


146 


DR.  A.  WALLER  ON  THE  MINUTE  STRUCTURE  OF  THE  PAPILLA 


frequently  with  an  irregular  pointed  extremity.  The  rest  of  the  tubes  still  eontinue 
in  close  contact,  and  when  they  have  attained  the  membrane  of  the  area,  end 
abruptly  in  an  irregular  manner,  some  in  a point,  some  club-shaped,  some  in  a spiral 
form,  others  like  small  funnels,  but  most  often  with  a kind  of  concentric  mouth. 

In  some  papillae  the  nerve-tubes  keep  close  together  until  their  termination,  which 
takes  place  immediately  at  the  surface  of  the  area  at  its  central  point.  Their  open 
mouths  are  closely  joined,  and  almost  interlaced  with  one  another.  In  others  the 
terminations  of  the  nerve  are  still  more  evident,  for  the  tubes  are  seen  expanding 
and  crossing  over  each  other  so  as  to  supply  as  equally  as  possible  each  of  the  areas 
enclosed  by  the  capillary  loops. 

Nerves  of  the  inferior  surface  of  the  tongue. — This  surface  presents  neither  conical 
nor  fungiform  papillae.  Its  epithelium  consists  of  flat  nucleated  scales,  extremely 
thin.  In  a portion  of  this  surface  removed  from  the  organ  and  interposed  between 
glass,  we  may  detect  abundant  convolutions  of  the  nerves,  similar  in  every  respect 
to  those  found  under  the  conical  papillae ; they  are  very  tortuous,  form  frequent 
loops,  and  are  reduced  to  the  state  of  nearly  single  tubes. 

Mucous  follicles. — These  are  seen  over  various  parts  of  the  upper  surface  inter- 
spersed among  the  papillae.  Their  appearance  at  the  surface  is  that  of  an  anal 
opening  generally  closed  during  life,  forming  a slightly  prominent  tumid  ring. 
After  death,  or  when  the  membrane  is  much  distended,  the  eye  penetrates  into  their 
interior,  where  an  active  ciliary  motion  exists.  When  the  surrounding  membrane  is 
denuded  of  its  scales,  we  perceive  around  the  opening  two  striated  muscular  fibres, 
forming  a curve  on  each  side,  and  performing  the  office  of  a sphincter.  The  follicle 
forms  a bottle-shaped  cavity,  exactly  like  the  small  follicles  over  the  skin  of  the  frog, 
particularly  near  the  anus.  It  is  supplied  by  a capillary  which  runs  close  by  it, 
without  encircling  or  spreading  over  it.  The  follicular  nerve  consists  of  one  or  two 
tubules,  and  makes  a single  or  double  coil  when  it  reaches  the  follicle. 

In  reeapitulating  these  observations,  we  find  in  the  frog  an  organ  of  taste  similar 
in  its  general  structure  to  that  in  man.  At  the  upper  surfaee  are  bodies  corre- 
sponding to  the  conical  and  fungiform  papillee.  At  the  inferior  surface  the  membrane 
is  smooth  and  without  anything  of  the  kind.  We  may  therefore  conclude  that  the 
upper  surface  has  the  faculty  of  taste  and  of  touch,  and  that  the  under  surface  is 
merely  tactile  as  in  our  own  species.  The  fungiform  papillee  consist  of  a membranous 
vesicle  or  utricule,  containing  coils  of  capillaries,  numerous  nerves,  and  muscular 
fibres,  and  probably  lymphatics.  Where  do  the  nervous  elements  which  these  bodies 
contain  extend  themselves?  We  invariably  find  that  they  terminate  at  a part  of  the 
utricule  where  the  membrane  is  so  transparent  that  we  may  almost  doubt  whether 
they  are  surrounded  at  all  by  a membrane.  This  is  the  area  which  I term  the  gusta- 
tory or  neuro-vascular,  where  the  action  of  the  nervous  radicels  is  performed,  which 
being  conveyed  to  the  brain  excites  an  impression  of  taste.  Another  element  ob- 
served in  this  area  is  the  existence  of  numerous  and  intricate  coils  of  capillary  vessels 


AND  NERVES  OF  THE  TONGUE  OF  THE  FROG  AND  TOAD. 


147 


which  surround  the  nervous  extremities  in  all  directions.  We  find  also  a zone  or 
belt  which  encircles  the  gustatory  area,  and  serves  principally  to  protect  and  support 
it.  Numerous  muscular  fibres  are  directed  towards  this  zone,  which  will  account 
for  the  partial  erectility  of  the  fungiform  papillae  on  certain  occasions. 

The  gustatory  area  is  placed  sometimes  at  the  extremity,  at  others  at  the  sides  of 
the  papillae.  Whether  this  difference  in  situation  be  connected  or  not  with  any 
difference  of  sensation,  it  is  impossible  to  determine  ; but  in  each  case  the  gustatory 
area  is  placed  conveniently  near  to  any  liquid  spread  over  the  tongue.  It  is  further 
observed  that  the  height  of  these  papillae  varies  with  that  of  the  surrounding  papillae 
conicae.  We  are  well-aware  that  it  is  only  when  in  solution  bodies  can  be  tasted. 
The  trituration  of  substances  in  the  mouth  has  the  effect  of  producing  this  wherever 
it  is  possible.  When  once  in  this  condition,  we  cannot  but  admire  the  beautiful  and 
simple  structural  arrangement  by  which  taste  is  effected.  The  membrane  of  the  gus- 
tatory area  is  so  exceedingly  thin  that  the  transudation  of  any  liquid  in  contact  with 
it  must  be  proportionately  rapid.  Accordingly,  the  open  extremities  of  the  nerves 
may  be  considered  as  immersed  into  the  solution  which  it  has  to  analyse,  whether  to 
reject,  or  to  allow  to  pass  on  to  the  stomach.  The  mysterious  action  by  which  the 
material  world  comes  in  contact  with  mind,  is  being  effected  under  our  closest 
scrutiny.  If  we  are  ever  to  penetrate  further  into  the  arcana  of  life,  may  we  not 
expect  to  do  so  by  observing  these  phenomena  while  the  vital  powers  are  intact  ? 
While  the  nerve  is  being  stimulated,  the  current  within  the  capillary  coil  is  continuing 
its  course,  and  it  requires  but  a slight  acquaintance  with  the  laws  of  imbibition  to 
recognize  that  in  this  case  the  sapid  solution  must  be  rapidly  eliminated,  and  that 
the  nerve  will  consequently  be  free  from  its  presence,  and  fresh  to  receive  a new 
impression. 

Tongue  of  the  Toad. 

Unlike  what  might  have  been  expected  from  the  habits  of  this  animal,  its  organ  of 
taste  is  less  developed  than  that  of  the  frog.  The  tongue  is  of  a similar  structure 
and  form,  and  is  covered  with  papillae  more  minute  and  simple.  The  fungiform 
papillae  are  less  numerous.  In  the  full-grown  animal  they  present  at  their  summit  a 
circular  capillary  enclosing  a fasciculus  of  nerve-tubes  closely  joined  together.  They 
also  contain  muscular  fibres,  and  are  provided  with  cilia. 

The  conical  papillae  are  less  distinct,  and  are  composed  rather  of  folds  or  rugae  of 
the  membrane  than  of  separate  bodies.  On  comparing  a frog  and  toad  of  the  same 
size,  we  find  in  the  latter  the  papillae  much  less  developed.  Taking,  for  example,  a 
toad  weighing  five  drachms,  we  find  the  epithelian  scales  over  the  dorsum  very 
indistinct,  and  the  surface  finely  granular.  The  fungiform  papillae  are  the  3-g-oth  of 
an  inch  in  thickness,  without  any  pedicel.  The  blood-vessels  form  two  or  three  loops 
at  the  summit  of  the  papilla.  The  nerve-tubules  are  much  less  numerous  than  those 
of  the  frog,  less  distinct  and  extremely  varicose.  The  summit  of  the  papilla  consists 

u 2 


148 


DR.  A.  WALLER  ON  THE  MINUTE  STRUCTURE  OF  THE  PAPILLA 


of  a granular  mass  of  a convex  form,  which,  when  viewed  at  the  edges,  appears  sur- 
rounded by  a fringe  of  epithelial  cells,  which  is  detached  after  a short  maceration. 
The  conical  papillae  rarely  exceed  the  y^^th  of  an  inch  in  height.  Maceration 
causes  them  to  swell  considerably,  so  as  to  attain  more  than  double  their  original 
size.  The  greatest  increase  is  at  their  summit  or  free  extremity,  and  the  papilla 
then  assumes  a flask-like  form.  Some  of  the  epithelial  cells  likewise  attain  an  ex- 
traordinary increase  of  size  by  maceration. 

Description  of  the  Plate. 

PLATE  XII. 

A portion  of  the  frog’s  tongue  removed  from  the  border  near  one  of  the  tubercles, 
as  viewed  with  a magnifying  power  of  350  diameters,  under  a slight  compres- 
sion. 

A.  Fungiform  papilla,  projecting  along  the  margin. 

B.  B.  Conical  papillae,  projecting  along  the  margin. 

C.  Border  of  the  tongue  with  vibratile  cilia,  seen  in  constant  movement  over 

the  fungiform  papillae.  The  depression  in  the  border  is  the  commence- 
ment of  a channel  formed  by  the  rugae  so  numerous  near  the  edges. 

D.  Small  mucous  follicle. 

E.  Apertures  of  the  conical  papillae. 

F.  A capillary  vessel  containing  blood-discs  and  corpuscles,  ascending  half- 

way up  the  papilla  conica. 

G.  External  zone  of  fungiform  papilla,  formed  of  epithelian  cells  which  are 

much  more  indistinct  and  laminated  over  the  neuro-vascular  area. 

H.  Neuro-vascular  area  containing  the  capillary,  the  gustatory  nerve,  and 

striated  muscular  fibre. 

I.  The  capillary  ascending  from  the  lower  surface  of  the  tongue  towards 

the  fungiform  papilla,  wherein  it  forms  coils,  making  its  exit  in  the 
same  direction  in  which  it  entered.  The  vessel  is  represented  in  a 
state  of  engorgement,  the  globules  compressed  and  indistinct. 

J.  The  gustatory  nerve,  likewise  derived  from  a branch  near  the  inferior 

surface,  entering  the  papilla  between  the  capillary.  Near  its  entrance 
it  makes  numerous  wavy  bends  of  a spiral  form.  The  tubules  become 
more  distinct  and  diffused  towards  their  extremities,  where  they  appear 
to  be  composed  of  separate  joints  from  the  coagulation  of  the  medulla 
of  the  tubule.  Their  extremities  in  this  example  appeared  all  of  them 
to  be  slightly  dilated,  and  with  a dark  point  at  their  termination,  giving 
them  the  appearance  of  ending  in  open  mouths. 

K.  Striped  muscular  fibres  ascending  vertically  into  the  papilla  among  the 

vessels  and  nerves,  becoming  indistinct  near  the  summit. 


r 


J^UITtoju .lASZZCXUJ.  ILaUm .JV.J48. 


f 


AND  NERVES  OF  THE  TONGUE  OF  THE  FROG  AND  TOAD. 


149 


L.  Striated  muscular  fibres,  forming  hoops  or  circles  beneath  the  mucous 

membrane ; they  are  left  plain  to  the  right  of  the  drawing  to  avoid 
complicating  the  figure. 

M.  Fibrous  tissue  of  an  elastic  nature  beneath  the  epithelium. 

N.  Tactile  nerves  forming  a network  over  the  muscular  fibre.  They 

merely  attain  the  base  of  the  conical  papillse. 

O.  An  agglomeration  of  nerve-tubules.  In  this  instance  they  appeared  to 

be  in  part  derived  from  the  gustatory  nerve  before  its  ascent  into  the 
papilla. 


. j 


j^nouiuii  9iit  liiiVnvMl  d^:-'  'i^>  eq’>oii  :jjui!mcir  /silft  •wjiif.^tuii  byui.v  ■ A 

o.t  Vinhmb  oiU rinJq  Jl  .i  ’yrA  \n\l  : inmifth'- Mi 

.!!i:?{lyii.J5vra  OiiJ  /i:U3i:-;  ' ••  -j  > .u:  'y>  ^ 

.■Si';<*-1  *!,Hiijy.'F  u !iih  ‘1970  ;!'t(>v/39ii  fi  ■gi;:i»iiHl[  '^!i!'.;i;r  ,;yT  s : 

< u hy-fi^ivqqji  i; i ar d J n i .gyl i)<l«J-77  i9n  1 ’ iK>i tiri ■> r<v u 'x  d ■ 

ytll  (jrfj:I  #i!'.aHi;  gii -i'!! 'i.'tl  !'.yYrr>l>  I’lnr,  ;ir  ;Hi  ' - 

„ , ^ • ' . ,,)!>  / '•'.  -•.■  ’ ■ ' -Y  .W(!  qiSiCj'-  '■" 

^ '■  ’.wjj-’ 


. f--' 


■ i 

, ■'.  I'i'lfi  *‘; 

■;T->iT;fy  < ' V.  ' ' ’ ; 


r ■•)':  A 


■^  . 

: /•' 


V \ '^10; , 

V V 1 -S  • 

, •s-'.v.iv  ’I/../;  V 


./>?''fr.'';^'-if\^';'  ■ I -V'  " 


• ■1*1  , ' V.  ' :,' 

' "h. 

V Ys  ": 


■ V'. 


'(  ’'Vh 


...  ’"•U^  ' . i^>'.''^-  i^ifi 


.K.  rv i •■■ 


.(  .j„''  . ■'  '.■ 


■'-Ak  '‘'w 


■}'  , ■ '■■'><' "'  Yij 

^ ,.  ;V 


.V 


O 


[ 151  ] 


XI.  On  the  Development  and  Homologies  of  the  Carapace  and  Plastron  of  the  Chelo- 
nian  Reptiles.  By  Professor  Owen,  F.R.S.  ^c. 

Received  November  16,  1848, — Read  January  18,  1849. 

Those  animals  to  which,  in  the  manifold  modifications  of  the  organic  framework,  a 
portable  dwelling  or  place  of  refuge  has  been  given,  in  compensation  of  inferior  powers 
of  locomotion  or  other  means  of  escape  or  defence,  have  always  attracted  especial 
attention ; and  of  them  the  most  remarkable,  both  for  the  complex  construction 
of  their  abode  as  well  as  for  their  comparatively  high  organization,  are  the  reptiles 
of  the  Chelonian  order.  The  expanded  thoracic -abdominal  case,  into  which,  in  most 
Chelonians,  the  head,  the  tail  and  the  four  extremities  can  be  withdrawn,  and  in  some 
of  the  species,  be  there  shut  up  by  moveable  doors  closely  fitting  both  the  anterior 
and  posterior  apertures,  as  e.  g.  in  the  Box-tortoises  {Cinosternon,  Cistudo),  has  been 
the  subject  of  many  and  excellent  investigations ; and  not  the  least  interesting  result 
has  been  the  discovery,  that  this  seemingly  special  and  anomalous  superaddition  to 
the  ordinary  vertebrate  structure  is  due,  in  a great  degree,  to  the  modification  of 
form  and  size,  and,  in  a less  degree,  to  a change  of  relative  position,  of  ordinary 
elements  of  the  vertebrate  skeleton. 

To  ascertain  the  precise  nature  and  extent  of  these  modifications,  in  other  words, 
to  determine  the  homologies  of  the  bony  framework  of  the  case  in  question,  is  the 
aim  of  the  present  communication. 

The  natural  dwelling-chamber  of  the  Chelonia 
consists  chiefly,  and  in  the  marine  species  {Che- 
lone)  and  mud-turtles  {Trionyx)  solely,  of  the 
floor  and  the  roof : side-walls  of  variable  ex- 
tent are  added  in  the  freshwater  species  {Emy- 
dians)  and  land-tortoises  {Testudinians).  The 
whole  consists  chiefly  of  osseous  ‘ plates  ’ with 
superincumbent  horny  plates  or  ‘ scutes,’  except 
in  the  soft  or  mud-tortoises  {Trionyx  and  Sphar- 
gis),  in  which  these  latter  are  wanting.  It  is 
requisite  briefly  to  allude  to  the  well-known 
composition  of  the  osseous  framework  of  this 
chamber  in  order  to  define  the  terms  by  which 
certain  parts  will  be  adverted  to  in  the  course 
of  the  paper. 

The  roof  or  ‘carapace’  (fig.  1)  consists  of  a 


Fig.  1. 


Carapace  of  the  Loggerhead  Turtle  {Chelo7ie  caouaiinu). 


152  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


‘ median  ’ series  of  symmetrical  plates  {ch,  « i to  ^ n),  and  of  two  ‘ lateral  ’ series  form- 
ing a pair  {pi  i to  pi  s),  the  whole  being  surrounded  by  a circle  of  ‘ marginal  ’ pieces 
{m  1 to  pp),  completed  anteriorly  by  ch,  the  first  of  the  median  series.  Of  the  median 
series  eight  i to  .s  s)  are  attached  to  the  spines  of  eight  subjacent  vertebrae  : the 
lateral  or  parial  plates  (pi  i to  pi  s)  are  attached  to,  and  more  or  less  blended  with, 
the  ribs  of  the  same  vertebrae,  and  the  ends  of  these  ribs  usually  articulate  by  gom- 
phosis  with  a corresponding  number  of  the  marginal  pieces,  of  which,  however,  there 
may  be  from  twenty-four  to  twenty-six,  including  the  two  median  and  symmetrical 
ones  {ch  and  py).  That  these  marginal  pieces  are  the  least  essential  parts  of  the 
carapace  is  shown  not  only  by  their  inconstant  number,  but  by  their  partial  or  total 
absence  in  some  of  the  soft-turtles  {Gymnopus,  Sphargis). 

In  the  present  communication  the  me- 
dian pieces  (51 — .sn)  are  called  the  ‘neural’ 
plates;  the  lateral  pieces (p/ 1— jo/  8)the  ‘cos- 
tal’ plates : the  term  ‘marginal’  is  restricted 
to  those  peripheral  pieces  which  form  pairs 
(mi tom  12) ; the  anterior  symmetrical  piece 
{ch),  constant  in  all  Chelonia,  is  called  the 
‘ nuchal’ plate  ; the  posterior  symmetrical 
piece  {py^,  which  is  wanting  in  all  the  Trio- 
nycidce,\?,  the ‘pygal’  plate.  I enumerate  the 
neural  plates  in  the  order  in  which  they  are 
numbered  by  Bojanus  in  the  Tab.  III.  and 
IV.  of  his  great  work*.  The  neural  arch 
connate  with  the  first  neural  plate (.si)  is  sup- 
ported partly  by  the  centrum  of  the  verte- 
bra to  which  the  first  pair  of  free  ribs  (fig. 2, 
c i)  is  articulated,  and  which,  therefore,  is 
reckoned  as  the  first  dorsal  vertebra : these 
ribs  are  small  and  slender,  attached  at  both  their  extremities,  the  outer  end  abutting 
against  the  under  part  of  the  first  pair  of  costal  plates,  which  they  help  to  sustain.  The 
second  to  the  ninth  dorsal  vertebrae  inclusive,  being  those  which  are  more  immediately 
connected  with  the  neural  and  costal  plates,  may  be  called  ‘ vertebrae  of  the  carapace:’ 
their  characters,  though  not  less  artificial  than  those  which  distinguish  the  ‘ dorsal  ’ or 
‘ lumbar  ’ vertebrae  of  other  reptiles,  are  much  more  marked  and  constant.  The  eighth 
vertebra  of  the  carapace  is  succeeded  by  a vertebra,  whicli  in  some  species  {e.  g.  Chelone 
caouanna,  fig.  2,  1 1)  supports  a pair  of  short  ribs,  in  others  {Trionyx)  none,  and  which  is 
therefore  reckoned  a ‘lumbar’  vertebra;  this  is  followed  by  two  other  vertebrae,  with 
short  and  thickened  ribs,  abutting  against  the  iliac  bones  and  representing  the  ‘ sacrum’ 
(fig.  2,  ^ 1) : as  these  three  vertebrae  are  not  immediately  united  with  the  ninth,  tenth 

^ Anatomia  Testudinis  Europsese.  Fol.  1819-1821. 


Fig.  2. 


Inner  view  of  the  carapace  of  the  Loggerhead  Turtle  {Chelone  caouanna). 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


153 


and  eleventh  ^ neural  plates,’  they  have  less  claim  than  the  first  dorsal  vertebra  to  be 
regarded  as  entering  into  the  composition  of  the  carapace. 

The  ‘ plastron  ’ (fig.  3)  or  floor  of  the  thoracic-abdo- 
minal chamber  consists  in  all  Chelonia  of  nine  pieces, 
for  which  the  terms  proposed  by  Geoffroy  St.  Hilaire 
may  be  retained,  if  used  in  an  arbitrary  sense  and 
without  implying  assent  to  the  hypothesis  that  first 
suggested  them.  The  median  and  symmetrical  piece 
of  the  plastron  (fig.  3)  is  the  ‘ entosternal’  {s),  the  four 
pairs,  counted  from  before  backwards,  are  respec- 
tively, the  ^ episternals  ’ {es),  ‘ hyosternals  ’ {hs),  ‘ hy- 
posternals’  {ps),  and  xiphisternals  ’ {xs). 

With  regard  to  the  ideas  that  have  been  entertained 
as  to  the  homologies  of  the  above-defined  osseous 
pieces,  it  would  be  a parade  of  names  without  adequate 
gain  to  the  discussion,  to  go  further  back  than  the  first 
edition  of  the  ‘‘Lecons  d’Anatomie  Comparee”  (1799),  in  which  Cuvier  refers  the 
chief  part  of  the  carapace,  viz.  the  ‘costal  plates,’  to  eight  pairs  of  dilated  ribs*"; 
the  neural  plates  he  describes  as  corresponding  in  number  with  the  vertebrie  of  which 
they  form  part'f-:  the  marginal  pieces  and  the  parts  (“plusieurs  os”)  of  the  plas- 
tron are  described  arbitrarily  and  left  undetermined. 

Geoffroy  St.  Hilaire,  entering  into  the  question  of  their  homologies  in  his 
memoir  on  the  genus  Trionyx,  published  in  the  year  1809,  and  adopting  the  Cuvierian 
idea  that  the  carapace  consisted  of  a development  of  dorsal  vertebrae  and  vertebral 
ribs,  argues  that  the  plastron  is  a greatly  expanded  sternum,  and  that  the  marginal 
pieces  are  the  cartilages  of  the  ribs  ossified,  or  ‘ sternal  ribs  ’ (“  cotes  sternales:|:  ”). 

In  the  collection  of  memoirs  forming  the  first  edition  of  the  ‘Ossemens  Fossiles,’ 
Cuvier  merely  cites  the  opinion  of  Geoffroy,  “ Ces  pieces  que  M.  Geoffroy  com- 
pare a la  partie  sternale  ou  cartilagineuse  de  nos  cotes  manquent  aux  tortues  molles," 


Fig.  3. 


* “La  carapace  des  Tortues  est  formee  par  les  dilatations  de  huit  cotes  ou  batons  osseux  qui  prennent  nais- 
sance  sur  les  unions  des  vertebres  et  se  terminent  a un  rebord  que  entourent  toute  la  carapace.”  Tom.  i.  p.  211. 

t “ On  remarque  en  dessus,  le  long  de  la  partie  moyenne,  une  rangee  de  petites  plaques  osseuses  joresque 
carrees,  unies  intimement  entre  elles  par  synarthrose,  qui  sont  en  meme  nombre  que  les  vertebres  dont  elles  font 
partie.”  Ib.  p.  211. 

+ “ La  difference  dans  le  nombre  des  pieces  du  plastron  et  du  sternum  des  oiseaux  pouroit  faire  croire  qu’il 
seroit  entre  dans  le  plastron  des  tortues  des  pieces  etrangeres  a la  composition  d’un  sternum,  comme  des  cotes 
sternales  ; idee  d’autant  plus  naturelle  a admettre,  que  les  parties  laterales  du  plastron  sont  terminees  par  un 
certain  nombre  de  digitations ; cependant  il  n’en  est  rien.  Les  analogues  des  cotes  sternales  ne  manquent 
point  dans  les  tortues;  elles  existent  dans  ces  pibces  articulees  dont  j’ai  parle  plus  haut,  et  se  voient  a la  suite 
des  cotes  vertebrates  ou  elles  forment  le  bord  des  carapaces.  Le  plastron,  ou  le  sternum  des  tortues  s’attache 
sur  ces  cotes  ou  pieces  sternales,  en  sorte  qu’il  ne  manque  rien  d’essentiel  dans  le  thorax  des  ces  animaux.” — 
Annales  du  Museum,  xiv.  p.  7 (1809). 

MDCCCXLIX.  X 


154  PROFESSOR  OWEN  ON  THE  DEVELOPiVlENT  AND  HOMOLOGIES  OF  THE 


&c.  (see  the  concluding  memoir  of  tom.  iv.  1812,  p.  2).  In  the  second  edition  of  the 
‘ Ossemens  Fossiles  ’ (tom.  v.  pt.  2.  1824),  Cuvier,  after  remarking  “that  the  mar- 
ginal pieces  do  not  correspond  exactly  to  the  vertebral  ribs ; that  the  first  of  the 
dilated  ribs  forming  the  carapace  joins  the  third  of  the  marginal  pieces ; and  that 
the  tenth  does  not  receive  any  rib,”  observes,  in  reference  to  the  latter  expression, 

“ ne  regoit  aucune  cote Ce  ne  pourroit  done  etre  aussi  que  sous  un  point  de  vue 

philosophique  que  Ton  regarderoit  les  pieces  marginales  comme  representant  les  car- 
tilages ou  parties  sternales  des  cotes.  Toutefois,  comme  il  y en  a onze,  ce  qui  est 
precisement  le  nombre  des  vertebres  dorsales  et  lombaires,  c’est  un  motif  pour  adopter 
ce  point  de  vue.  Les  deux  premieres  et  les  deux  dernieres  servaient,  comme  on  I’a  dit 
en  d’autres  occasions,  des  cotes  sternales  auxquelles  leurs  cotes  vertebrales  manque- 
roient,”  p.  200.  In  the  posthumous  edition  of  the  ‘ Legons  d’ Anatomic  Comparee,’ 
Cuvier  gives  only  grounds  for  rejecting,  not  any  for  adopting,  the  views  of  Geoffrov, 
in  regard  to  the  marginal  pieces,  and  observes,  “ On  a considere  ces  pieces  comme 
analogues  aux  portions  sternales  des  cotes : il  faut  avouer  au  moins  qu’elles  ne  leur 
repondent  pas  pour  le  nombre,  et  que  dans  les  trionyx  sur-tout,  elles  ne  leur  corre- 
spondent point  pour  la  position.  C’est  a la  troisieme  ou  a la  quatrieme  que  com- 
mence leur  engrenage  avec  les  deux  pieces  moyennes  du  sternum  ; il  finit  a la  huitieme, 
mais  dans  les  tortues  de  mer  cette  union  n’a  pas  lieu.”  Tom.  i.  1835. 

Bojanus,  who  has  given  the  most  complete  and  masterly  analysis  of  the  emydian 
modification  of  the  carapace  and  plastron,  calls  the  neural  plates  ‘ processus  spinosi 
vertebrarum  dorsi,’  the  costal  plates  ‘costse,’  and  the  bones  of  the  plastron  ^sternum:’ 
he  offers  no  homology  of  the  ‘marginal’  plates,  but  retains  for  them  the  absolute 
names  of  ‘ ossa  marginalia*.’ 

The  eminent  physiologists  and  comparative  anatomists  of  our  own  country  have 
not,  however,  partaken  of  this  reserve  of  the  great  French  master  of  the  science,  or 
of  the  celebrated  German  monographer,  towards  the  Geoffroyan  hypothesis  of  the 
marginal  pieces.  Dr.  Roget,  in  his  ‘ Bridgewater  Treatise,’  after  a brief  but  clear 
summary  of  the  general  structure  and  uses  of  the  carapace  and  plastron,  says,  “ We 
find,  however,  on  a more  attentive  examination,  that  all  the  bones  composing  the 
skeleton  in  other  vertebrated  animals  exist  also  in  the  Tortoise;  and  that  the  bony 
case  which  envelopes  all  the  other  parts  is  reg-lly  formed  by  an  extension  of  the 
spinous  processes  of  the  vertebrae  and  ribs  on  the  one  side,  and  of  the  usual  pieces 
which  compose  the  sternum  on  the  other.”  Vol.  i.  1834,  p.  464.  The  learned  Pro- 
fessors of  Comparative  Anatomy  in  University  College  and  King’s  College,  London, 
have  in  like  manner  adopted  absolutely  the  determinations  of  Geoffroy  St.  Hilaire, 
although  the  former  admits  that-f-,  “Looking  at  the  singular  exterior  of  these  tortoises, 
shielded  in  a solid  case  like  a molluscous  animal  in  its  shell,  we  should  scarcely  expect 
to  find  that  this  dense  osseous  covering  enveloping  the  whole  body  consists  of  the  same 

* Op.  cit.  p.  12. 

t Lancet,  February  8,  1834.  See  also  Prof.  Grant’s  ‘ Outlines  of  Comparative  Anatomy,’  8vo,  1835,  p.  82. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


155 


bones  which  compose  the  human  skeleton:”  and  I must  frankly  avow  that  my  expec- 
tation of  such  a discovery  was  so  small  as  to  beget  neither  surprise  nor  disappointment 
when  the  result  of  my  researches  into  the  development  of  the  parts  demonstrated  on 
how  superficial  a view  it  had  been  entertained. 

Professor  Rymer  Jones,  in  his  beautifully  illustrated  ‘ General  Outline  of  the  Animal 
Kingdom,’  adopting  Cuvier’s  determination  of  the  ‘carapace’  and  Geoffroy’s  of  the 
‘ plastron,’  observes,  “ The  margin  of  the  dorsal  ribs  is  further  enlarged  by  a third 
set  of  flat  bones,  apparently  representing  the  sternal  ribs  of  the  Crocodile.”  8vo,  1841, 
p.  553.  In  his  article  Reptilia,  however,  in  Todd’s  Cyclopsedia,  Part  32,  August, 
1848, — the  latest  opinion  on  the  subject  which  has  been  published, — the  Pi-ofessor 
affirms,  “these  marginal  plates  cannot  be  otherwise  regarded  than  as  the  representa- 
tives of  the  sternal  ribs  of  the  Crocodiles  and  other  Saurians.”  P.  266. 

The  German  authors  of  standard  works  on  comparative  anatomy,  with  the  excep- 
tion of  Meckel=^,  have  manifested  no  such  general  acquiescence  in  the  views  of 
Geoffroy  St.  Hilaire,  as  that  which  characterises  those  of  our  countrymen  above- 
cited.  Carus,  for  example,  originally  regarded  the  immoveable  ‘ costal  plates  ’ of  the 
carapace  as  much-developed  transverse  processes,  and  the  thorax  of  the  Tortoise  to 
be  “only  a more  perfect  development  of  the  ribless  and  imperfect  thorax  of  the 
Frog-f-;” — a view,  however,  in  which  his  able  English  translator  does  not  concur^; 
and  which  Carus  himself  abandons  in  the  second  edition  of  his  work.  He  there 
states  that  the  remarkable  and  anomalous  skeleton  of  the  trunk  of  the  Chelonia  may 
be  explained  by  recognising  how  certain  plates  belonging  primitively  to  the  dermal 
skeleton  are  applied  or  adapted  to  the  vertebrae,  the  ribs  and  the  sternum  the  idea, 
however,  is  neither  explained  in  detail  nor  supported  by  any  fact  of  development,  but 
is  rather  obscured  by  such  fancies,  as  that  the  bodies  of  the  vertebrae  of  the  carapace 
are  not  formed,  as  usual,  on  the  under  side,  but  on  the  upper  side  of  the  vertebral 
column  in  the  place  of  the  spinous  processes,  which  Carus  affirms  not  to  exist  I], 

Dr.  Peters^  adopts  the  view  that  the  carapace  includes  dermal  pieces  besides  the 
vertebrae  and  ribs  ; and  that  the  plastron  consists  of  a subdivided  sternum  enlarged 
by  combination  with  ossified  parts  of  the  integument. 

Professor  Wagner  has  given  us  an  opportunity  of  judging  of  the  sense  in  which  he 

* System  der  Vergleichenden  Anatomie,  Zweiter  Theil,  Erst.  Abth.  pp.  407,  408. 

t Introduction  to  Comparative  Anatomy,  by  Gore,  8vo,  1827,  p.  147. 

J See  the  note  at  the  same  page,  where  the  Geoffroyian  interpretation  is  given,  as  more  correct. 

§ “ Die  Bildung  des  Rumpfskelett’s  nur  dadurch  erklarlich  wird,  das  man  einsehen  lernt,  wie  durch  Anbil- 
dung  eigner,  urspriinglich  dem  Hautskelet  angehdriger  Flatten  an  Riickgrath,  Rippen  und  Brustbein,  die  auf 
den  ersten  blick  so  sonderbar  abweichende  Bildung  des  Riicken-  und  Bauchschildes  zu  Stande  kommt.”  Lehr- 
buch  der  Vergleich."^^^omie,  8vo.  Bd.  i.  p.  164. 

II  “ Am  Riickenschilde  das  vbllige  Verwachsen  der  Wirbel,  deren  kdrper  hier  nicht  wie  gewbhnlich  an  der 
untern,  sondern  an  der  obern  Wirbelseite,  statt  naturlich  ganz  fehlenden,  und  durch  die  darauf  gelegten  Kno- 
chenplatten  des  Hautskelets  ersetzlen  Dornfortsatze  ausgebildet  sind.”  Ib.  p.  165. 

^ Observationes  ad  Anatomiam  Cheloniorum,  1838. 

x 2 


156  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


understood  Carus’s  idea,  by  the  figure  of  the  skeleton  of  a young  Sea-turtle  {Chelone 
caoiianna),  which  he  explains  in  his  excellent  ‘ leones  Zootomicse,’  fol.  1841*,  Tab. XIV. 
fig.  12  ; where  a are  the  ribs,  b the  vertebral  bodies,  c the  neural  arches  (bogentheile), 
d the  neural  spines,  and  ee  the  median  row  of  dermal  bones  (‘mittlere  Reihe  der 
Hautknochen,’  p.  17).  Now  these  latter,  in  the  figure,  are  six  in  number,  extending 
from  one  end  of  the  carapace  to  the  other,  whilst  the  subjacent  neural  spines  agree 
in  number  with  the  vertebrse,  of  which  there  are  twelve  between  the  scapula  and 
ilium.  It  is  plain,  therefore,  that  the  horny  ‘vertebral  scutes,’  as  they  are  called  in 
Erpetology,  are  here  the  parts  supposed  to  represent  the  dermo-skeleton,  and  that 
the  bony  ‘ neural  plates  ’ are  regarded  as  the  spinous  processes,  agreeably  with  the 
Cuvierian  view. 

Prof.  Rathke'I'  has  recently  propounded  another  modification  of  the  combined 
dermo-  and  endo-skeletal  hypothesis  of  Carus.  Finding  that  there  were  no  osseous 
plates  developed  independently  in  the  corium  and  afterwards  coalescing  with  the 
neural  spines  and  ribs,  as  Carus  and  Wagner  describe,  he  concludes  that  the  cara- 
pace of  the  Chelonia  is  composed  exclusively  of  endo-skeletal  elements,  but  that  the 
plastron  as  exclusively  consists  of  exo-skeletal  parts  or  dermal  bones,  in  which  cate- 
gory also  he  places  the  ‘marginal  pieces,’  sufficiently  proved  by  the  Trionyx  and 
Sphargis  to  be  not  essential  to  the  composition  of  the  carapace. 

The  special  deductions  by  Rathke  will  be  compared,  in  the  sequel,  with  my  own 
observations  on  the  development  of  the  carapace  in  the  Chelonia ; but  it  will  be  ob- 
vious, from  the  conflicting  opinions  on  the  nature  and  homologies  of  the  chelonian 
skeleton,  published  within  the  last  ten  or  fifteen  years,  that  the  question  is  far  from 
having  been  satisfactorily  settled ; and  that  no  one  can  be  regarded  as  giving  the  re- 
quisite description  of  the  carapace  and  plastron  who  merely  adopts  the  determina- 
tions of  Geoffroy,  or  Carus  or  Rathke,  without  first  testing  them  by  an  appeal  to 
nature,  and  assigning  the  grounds  of  his  acceptance,  rejection  or  modification  of  such 
determinations. 

Commencing  by  the  way  of  a comparison  of  the  skeletons  of  fully-developed  Ver- 
tebrata,  and  assuming  for  the  purpose  of  such  comparison  that  the  thoracic-abdo- 
minal case  is  a modification  of  parts  of  the  endo-skeleton,  as  Cuvier,  Geoffroy  and 
Meckel  believed,  I propose  in  the  first  plaee  to  test  the  homologies  which  have  been 
generally  accepted  in  this  country,  and  of  which,  as  regards  the  ‘ marginal  plates,’  so 
positive  an  opinion  has  been  recently  published. 

Geoffroy  St.  Hilaire  was  guided,  as  is  well  known,  to  his  conelusions  by  the 

* “ Hier  ist  das  skelet  einer  jungen  Seeschildkrote  (fig.  xii)  zu  vergleichen,  wo  man  sieht,  dass  Wirbelsaule, 
Rippen  und  Brustbein  in  ihrer  ursprunglichen  Anlage  von  dem  eigentlichen  Riicken-  und  Briistschild  ganz 
getrennt  sind ; das  dieses  eigentlich  aus  isolirten  Verknocherungen  in  der  Haut  entsteht,  welche  erst  spater  mit 
Knochenskelet  verwachsen.”  p.  xii. 

t Sur  le  development  des  Cheloniens.  Annales  des  Sciences,  Mars,  1846 ; and  Ueber  die  Entwickelung  der 
Schiidkroten.  4to.  1848,  p.  122. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


157 


analogy  of  the  thorax  of  the  Bird : but  they  are  not  elucidated  by  any  special  de- 


Fig.  4. 


Thoracic  segment,  Tortoise. 


scriptions  or  figures.  They  will  be,  per- 
haps, best  understood  by  comparing  the 
subjoined  view  of  a segment  of  the 
thoracic-abdominal  case  of  the  Tortoise 
(fig.  4)  with  the  corresponding  view  of 
the  homologous  segment  in  the  Bird 
(fig.  5) ; in  both  of  which  c is  the  verte- 
bral body  or  ^centrum,’  n the  neural 
arch,  m the  neural  spine,  pi  is  the  ver- 
tebral rib  (pleurapophysis),  h (the  outer 
letter  in  fig.  4)  is  the  ossified  sternal  rib 
(heemapophysis),  and  hs  the  haemal  spine 
or  ‘ sternum.’  In  this  comparison  it  is 
supposed  that  the  primitive  median  divi- 
sion of  the  sternum  is  retained  in  the 
cold-blooded  reptile,  and  that  the  keel, 
or  ‘ entosternal  ’ piece  {hs'),  continues 
distinct,  but  is  developed  in  breadth  in- 
stead of  depth.  No  one,  however,  has 
been  able  to  adduce  any  example  from 
the  class  of  birds  in  which  the  lateral 
moieties  of  the  broad  sternum  are  deve- 
loped each  from  four  distinct  centres, 
answering  to  the  four  lateral  or  parial 
pieces  in  the  plastron  of  the  Chelonia  {es, 
hs,  ps  and  xs,  fig.  3). 

The  homologies  of  the  carapace  and 
plastron,  regarded  as  developments  of 
the  endo-skeleton,  appear,  hitherto,  not 
to  have  been  elucidated  by  any  other 
comparison,  save  that  by  Carus  with  the 
thorax  of  the  Frog.  Yet  the  chelonians 
have  nearer  affinities  to  the  crocodiles 
than  to  either  birds  or  batrachians ; and 
a comparison  of  the  thoracic-abdominal 
part  of  the  skeleton  of  a crocodile  ap- 
pears to  give  correspondingly  closer  illus- 
trations of  the  nature  of  the  peculiarities 
of  that  in  the  Tortoise.  , In  the  sub- 
joined view  of  the  segment  of  the  thorax  of  a crocodile  (fig.  6),  it  will  be  observed 


7»  s* 

Thoracic  segment,  Bird. 

Fig.  6. 


Thoracic  segment,  Crocodile. 


158  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


that  a distinct  piece  h!  is  interposed  between  the  pleurapophysis  {pi)  and  hseina- 
pophysis  (A),  and  it  is  less  completely  ossified  than  either  of  those  elements.  The 
sternum  hs  is  a single  symmetrical  rhomboidal  plate,  of  which  a narrow  median  por- 
tion only  is  completely  ossified.  With  the  endo-skeletal  segment  is  combined,  in 
the  figure,  parts  of  the  corresponding  ossified  segment  of  the  exo-skeleton,  which 
parts  are  covered,  like  the  expanded  parts  of  the  carapace  of  the  Chelonia,  by 
thick  cuticular  scutes.  According  to  this  analogy,  c being  the  centrum  and  ns  the 
neural  arch  and  spine,  sc  answers  to  the  detached  dermal  bony  plate  sc  in  fig.  4. 
The  head,  neck  and  continuous  slender  part  of  the  rib  {pi,  fig.  6)  answers  to  the 
pleurapophysis  {pi)  in  fig.  4,  and  the  expanded  plate  {sc',  fig.  4)  answers  to  the  lateral 
bony  dermal  plates  {sc',  sc',  fig.  6):  the  marginal  plate  A,  A',  fig.  4,  occupies  the  place  of 
the  intercalated  costal  piece  A',  fig.  6 : the  hyosternal  A,  ^s,  fig.  4,  answers  to  the  heem- 
apophysis  or  ossified  cartilage  of  the  rib  (A,  fig.  6),  the  other  parial  pieces  also  being 
expanded  hsemapophyses ; and  the  entosternal  lis  (fig.  4)  alone  represents  the  simple 
sternum  /is  in  the  Crocodile:  in  brief,  the  figures  within  the  segment  fig.  4,  indicate 
the  homologies  according  to  the  Crocodile  (fig.  6),  those  without  or  below  the  segment 
(fig.  4)  indicate  the  homologies  according  to  the  Bird,  fig.  5. 

In  this  comparison  it  will  be  seen  that  the  mesial  end  of  the  costal  plate  (^c',  fig.  4), 
which  quits  the  rib  to  articulate  with  the  vertebral  plate  (^c)  in  the  Tortoise,  is  not  the 
homologue  of  the  tubercle  of  the  rib  which  articulates  with  the  diapophysis  c?,  fig.  6, 
in  the  Crocodile:  the  true  endo-skeletal  pleurapophyses,  or  vertebral  ribs,  of  the 
Chelonians  I regard  as  being  simple,  and  articulated  by  a head  only  to  the  central 
part  of  the  vertebra,  as  in  other  Reptilia  which  have  but  one  ventricle  of  the  heart. 
They  are  almost  straight,  and  so  far  resemble  the  free  ribs  (pleurapophyses),  which 
project  from  a few  of  the  dorsal  vertebrae  in  the  Pipa  or  Surinam  Toad. 

Were  the  large  and  complex  abdominal  haemapophyses  of  the  Plesiosaur  (fig.  7,  A) 
to  coalesce  on  each  side,  they  would  form  two  lateral  masses  with  their  extremities 
projecting  outwards  and  inwards,  like  the  teeth  of  the  hyosternals  {As)  and  hypo- 
sternals  {ps)  in  the  plastron  of  the  Turtles  and  Trionyces  (figg.  3 and  8). 

In  olfering  the  comparison  of  the  thoracic-abdominal  segment  of  the  Crocodile 
with  that  of  the  Chelonian  to  the  consideration  of  Comparative  Anatomists,  my  ob- 
ject has  been  rather  to  show  that  the  subject  admits  of  more  than  one  view,  and  re- 
quires further  investigation,  than  to  substitute  merely  by  such  comparison  a different 
homological  hypothesis  from  that  whieh  has  hitherto  prevailed  in  this  country ; being 
conscious  that  without  the  illustrations  of  which  such  hypothesis  may  be  susceptible, 
it  would  be  of  as  little  real  avail  in  attaining  to  a true  knowledge  of  the  vertebrate 
organization  of  the  CJielonia  as  the  similarly  unconfirmed  view  of  Geofproy  St.  Hi- 
laire must  be  considered  to  be.  The  guide  to  our  choice  of  either  of  these,  or  of  any 
other  view  that  has  been  offered  of  the  nature  and  signification  of  the  thoracic- 
abdominal  case  of  the  Chelonia,  must  be  the  light  afforded  by  a true  perception  and 
explanation  of  the  phenomena  of  its  development. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


159 


The  youngest  Chelonian  which  I have  had  the  opportunity  of  examining  has  been 
the  embryo  of  the  common  Turtle  {Chelone  My  das),  not  quite  an  inch  in  length 
(PI.  XIII.  figs.  1,  2,  3).  At  this  period  the  broadest  part  of  the  animal  is  the  head, 
across  the  large  prominent  eye-balls.  The  neck  is  shorter  than  the  head,  the  cara- 
pace is  a long  narrow  ellipsoid,  more  convex  than  in  the  adult,  defined  by  a feebly- 
indicated,  thickened  border : the  region  of  the  plastron  (fig.  3j  is  flatter,  perforated 
by  the  large  vitelline  duct  and  vessels  (u).  The  scapular  arch  (fig.  2 a,  si,  52)  divides  the 
base  of  the  neck  from  the  fore-part  of  the  carapace  and  plastron,  and  the  anterior 
and  posterior  limbs  present  the  simple  form  of  undivided  paddles,  which  they  after- 
wards retain  in  this  and  other  marine  species.  Although  the  ribs  (fig.  1 a,  1 to  ho) 
are  visible  through  the  integument  of  the  back,  and  the  slender  entosternum  (fig.  3 a,  s) 
and  two  transverse  linear  rudiments  of  the  plastron  {hs  and  ps),  on  each  side,  are  more 
obscurely  seen  beneath  the  integument  of  the  abdomen,  yet  the  corium  covering 
these  parts  is  thicker,  and  its  texture  denser  than  in  the  embryo  of  the  lizard  or  that 
of  the  fowl  of  corresponding  size  and  development ; the  general  resemblance  in  the 
form  of  the  body  being  very  close  at  this  period,  to  the  bird,  by  reason  of  the  nor- 
mal proportions  of  the  trunk  and  the  shortness  of  the  tail.  The  most  advanced 
parts  of  the  osseous  system  are  plainly  those  which  belong  to  the  endo-skeleton,  and 
which  at  this  period  deviate  comparatively  little  from  the  normal  type.  As  my  pre- 
sent object  relates  to  the  thoracic-abdominal  case,  I shall  confine  my  remarks  chiefly 
to  that  part  of  the  skeleton. 

Ossific  matter  has  begun  to  be  deposited  in  the  cartilaginous  foundations  of  the 
neurapophyses  (figs.wi — wio,  1 a,  2 a),  and  of  the  pleurapophyses  {di — 1 10),  but  not 
in  the  neural  spines  or  the  centrums. 

Ten  pairs  of  pleurapophyses  (dorsal  or  vertebral  ribs)  have  been  established,  much 
more  nearly  equal  at  the  present  than  at  a subsequent  period ; the  first  {d  1)  and  the 
two  last  (c?9  and  ho)  being  the  shortest:  all  of  them  are  simple,  slender,  cylindrical, 
slightly  bent  towards  the  ventral  surface,  terminating  freely  near  the  thickened  bor- 
der of  the  dermal  basis  of  the  carapace.  The  scapulae  (ih.bl)  closely  resemble  the 
other  pleurapophyses  : it  is  impossible  to  mistake  their  general  homology  as  the  same 
elements  of  the  vertebral  segment : they  are  equally  simple  and  cylindrical,  and  their 
ossification  has  made  the  same  progress : but  their  position  is  more  nearly  vertical, 
with  the  upper  end  abutting  against  the  fore-part  of  the  first  thoracic  rib  (c^l),  and 
the  lower  end  bent  inwards  towards  the  entosternum  {s) ; the  position  is  very  simi- 
lar to  that  which  the  scapula  presents  in  the  correspondingly  developed  embryo  of 
the  bird,  in  which,  by  a subsequent  movement  of  backward  rotation,  the  slender  rib- 
like scapula  comes  to  overlap  the  anterior  thoracic  ribs : but  the  primitive  vertical 
position — the  more  normal  position  in  relation  to  the  archetypal  skeleton — is  retained 
throughout  life  in  the  Chelonia  as  in  the  Monotremata.  In  the  region  of  the  plastron 
the  entosternum  is  represented  by  a slender  median  cartilage,  pointed  behind  (fig. 
3 a,  5)  the  hyosternals  {hs)  by  a pair  of  transverse  cartilages,  commencing  near  the 


160  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


median  line  anterior  to  the  umbilical  aperture  {u),  and  arching'  outwards,  forwards, 
and  slightly  upwards  to  near  the  ends  of  the  third  pair  of  ribs  : the  hyposternals  {ps) 
are  represented  by  a similar  transverse  pair  of  slender  cartilages,  with  a tendency  to 
bifurcate  at  their  extremities.  The  cartilaginous  foundations  of  the  episternals  and 
xiphisternals  have  a not  very  definite  linear  form : the  coracoids  (fig.  1 a,  52)  are  more 
plainly  distinguishable ; I at  first  mistook  them  for  the  episternals.  The  rudimental 
hyosternals  and  hyposternals  at  this  period  repeat  the  characters  of  the  sternal  or 
abdominal  ribs  (haemapophyses)  in  the  Crocodile ; the  entosternum  represents  the 
thoracic  sternum  of  the  Crocodile. 

The  thick  and  somewhat  dense  corium  of  the  carapace,  covering  the  rudiments  of 
the  neural  arches  and  pleurapophyses,  when  examined  under  a power  of  300  linear 
diameters,  does  not  present  exclusively  the  fine  filamentous  interlaced  structure  of 
cellular  tissue  in  progress  of  condensation  into  derm,  as  in  the  embryo  bird ; but 
includes  oblong  nucleated  cells,  likeThose  of  cartilage,  which  along  the  middle  line 
of  the  back  are  arranged  in  groups  of  linear  series  radiating  from  a centre  corre- 
sponding with  the  point  of  convergence  of  each  pair  of  neurapophyses,  and  connected 
with  the  extremities  of  those  cartilages  by  a mass  of  cartilage-corpuscles  holding  the 
place  of  the  neural  spines. 

The  cartilage-corpuscles  in  the  firm  semiopake  part  of  the  corium  covering  the 
ribs,  show  traces  of  linear  arrangement  at  right  angles  to  the  ribs,  or  in  the  axis  of 
the  carapace ; especially  near  the  proximal  ends  of  the  middle  ribs.  The  thickened 
border  which  defines  the  carapace  is  formed  almost  entirely  of  oblong  nucleated  car- 
tilage-corpuscles, pretty  closely  aggregated  and  without  observable  definite  arrange- 
ment. The  stratum  of  cartilage-corpuscles  in  the  substance  of  the  corium  of  the 
plastron  is  thinner  than  that  of  the  carapace  : something  like  a linear  radiated 
arrangement  of  these  maybe  discerned  at  the  parts  corresponding  to  near  the  mesial 
ends  of  the  hyosternals  and  hyposternals  ; but  they  are  for  the  most  part  irregularly 
and  more  thinly  scattered  in  the  fibrous  tissue  than  on  the  carapace. 

Homologically  I conceive  that  this  basis  for  future  ossification,  being  situated  in 
the  substance  of  the  skin,  must  be  held  to  be  the  groundwork  of  a dermal  skeleton ; 
and  that,  whether  ossification  extends  into  such  basis  from  the  subjacent  ossifying 
parts  of  the  endo-skeleton,  or  whether  it  commences  independently  in  the  dermal 
cartilage,  and  afterwards  unites  with  the  deeper-seated  bones,  does  not  affect  such 
homological  relation : in  other  words,  that  a dermal  bony  scute,  whether  it  be  con- 
nate or  become  confluent*  with  a part  of  the  endo-skeleton,  is  still  essentially  a der- 
mal bone. 

But  although,  with  regard  to  most  of  the  superadditions  to  the  endo-skeletal  basis 
of  the  carapace,  I have  not  been  able  to  distinguish  a period  of  the  development  of 
an  independent  centre  of  ossification,  yet  the  superadded  parts,  ossified  from  pre- 

* I use  the  terms  ‘ connate  ’ and  ‘ confluent  ’ in  the  sense  defined  in  my  work  on  the  ‘Archetype  of  the  Ver- 
tebrate Skeleton,’  8vo,  p.  49. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


161 


existing  subjacent  vertebral  elements,  long  retain  a very  peculiar  and  distinct  charac- 
ter of  osseous  texture,  well-displayed  in  the  development  of  the  carapace  and  plastron 
of  the  land-Tortoises,  which  1 next  proceed  to  describe. 

Fig.  4 gives  an  outside  view  of  the  incipient  carapace  of  a very  young  Testudo 
indica : fig.  5 shows  an  inside  view  of  the  same  carapace,  and  figs.  6 and  7 similar 
views  of  the  plastron  of  the  same. 

The  carapace  is  not  quite  three  inches  in  length.  On  removing,  after  maceration, 
the  well-developed  epidermal  scutella,  the  following  ossified  parts  were  seen : — the 
nuchal  (cA),  the  pygal  {py),  and  ten  intervening  neural  plates  (s  i to  s lo) ; mostly 
of  a subquadrate  form,  but  of  irregular  size,  and  with  rounded  angles  and  ill-defined 
outlines;  the  tenth  plate  (510)  being  insulated  between  the  ninth  (.sq)  and  the  pygal 
plate  (py).  On  each  side  of  the  middle  row  of  neural  plates  is  a series  of  eight  simi- 
larly-sized, triangular  or  rhomboidal  plates  (fig.  4,j9/i — jo/8),each  of  them  marked  on 
their  outer  surface  with  a triradiate  linear  impression  formed  by  the  junction  of  two 
costal  scutella  with  one  vertebral  scutellum,  or  of  one  vertebral  with  two  costal  scu- 
tella; excepting  the  penultimate  or  seventh  plate  (ply).  Around  the  border  of  the 
carapace  are  eleven  pairs  of  marginal  plates  (m  1 — m n),  exclusive  of  the  nuchal  (ch) 
and  pygal  (py)  plates.  The  wide  interval  between  the  marginal  and  the  incipient 
costal  plates  is  occupied  by  the  corium  and  its  stratum  of  cartilaginous  cells,  sup- 
ported by  the  eight  pairs  of  ribs  of  the  carapace  (fig.  5,  d 2 — d 9),  by  the  first  pair  of 
short  dorsal  ribs  (d  1),  by  the  pair  of  shorter  lumbar  ribs,  and  by  the  rib-like  upper 
and  outer  extremities  of  the  hyosternals  (hs)  and  hyposternals  (ps),  which  ascend 
beyond  the  marginal  plates.  The  extremities  of  the  ribs  do  not  as  yet  join  the 
marginal  plates.  The  nuehal  plate,  the  ninth  and  tenth  neural  plates,  the  pygal 
plate,  and  all  the  marginal  plates  are  independent  osseous  developments  in  the  sub- 
stance of  the  derm : the  other  neural  plates  (s  i — s s)  are  connate  with  the  neural 
spines  of  the  second  to  the  ninth  dorsal  vertebrae  inclusive,  and  the  costal  plates  are 
similarly  connate  with  the  upper  surface  of  the  ribs  of  the  same  vertebrae  at  varying 
distances  from  their  proximal  ends.  The  first,  second,  fourth,  sixth  and  eighth  ribs 
of  the  carapace  are  continued  from  beneath  the  outer  angles  or  apices  of  the  corre- 
sponding costal  plates  (pi  i,  pi  2,  pi  4,  pi  e,  pi  s),  but  the  third,  fifth  and  seventh  ribs 
of  the  carapace  are  continued  from  beneath  the  middle  of  that  side  of  the  correspond- 
ing, triangular  costal  plate  which  seems  to  form  its  base. 

The  neural  plates,  the  costal  plates,  and  the  marginal  plates,  whether  attached  to 
vertebral  elements  or  detached,  are  lodged  in  the  substance  of  the  derm,  and  form  a 
stratum  of  bones  superficial  to  the  ossified  parts  of  the  endo-skeleton.  A strong  argu- 
ment for  regarding  the  costal  plates  as  dermal  ossifications  rather  than  processes  or 
continuations  of  the  endo-skeletal  elements,  to  which  they  are  attached,  may  be  drawn 
not  only  from  the  place  of  development  of  their  cartilaginous  basis  or  bed,  but  also 
from  the  period  of  their  ossification  ; and  their  relative  position  to  the  ribs  with  which 
they  are  connate. 

MDCCCXLJX.  Y 


162  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


In  the  embryo  Testudo  indica  the  uniformly  slender  pleurapophyses  {d  1 — d9,  fig.  5) 
are  ossified  nearly  throughout  their  whole  length  before  the  ossification  of  the  costal 
plateSj  usually  regarded  as  their  expanded  tubercles,  commences  : and  the  beginning 
of  the  superadded  bone*  is  not  at  the  same  point  in  each  rib,  as  might  have  been  ex- 
pected if  it  were  the  exogenous  process  called  ‘ tubercle  ’ of  the  rib.  The  costal 
plates  are  situated  in  the  young  Testudo  indica  (Plate  XIII.  figs.  4 and  5,  ph — s) 
alternately  nearer  to  and  farther  from  the  head  of  the  rib ; and  their  presence  seems 
to  be  determined  rather  by  the  angle  of  union  of  the  superincumbent  vertebral 
scutella  with  the  lateral  or  costal  scutella,  than  by  the  necessity  for  additional 
strength  in  the  articulation  of  the  ribs  with  the  spine.  Ossification  commences  at  the 
point  from  which  the  three  impressions  radiate,  and  as  this  point  is  nearer  the  median 
line  at  the  median  apex  of  the  costal  scutellum  than  at  the  lateral  apex  of  the  verte- 
bral scutellum,  the  resulting  plates  of  bone  are  alternately  further  from  or  nearer 
to  the  middle  line ; and  the  first,  third  and  fifth  costal  plates  have  advanced 
along  the  proximal  end  of  the  rib  so  as  to  join  the  neural  plates,  whilst  the  second, 
fourth  and  sixth  costal  plates  leave  a portion  of  the  proximal  end  of  the  rib  uncovered 
and  crossing  the  space  between  the  incipient  costal  plate  and  the  neural  plate./  In 
regarding  these  incipient  ossifications,  extending  into  the  substance  of  the  corium 
and  receiving  the  impressions  of  the  epidermal  scutes  as  the  developed  ^tubercle’  of 
the  ribs,  as  Rathke  has  endeavoured  to  illustrate  in  Tab.  III.  figs.  11  (Tortoise),  12 
and  13  (Chick)  of  his  elaborate  Monograph  f,  we  are  compelled  to  suppose  that  each 
successive  rib  in  the  Tortoise  has  a different  position  of  its  tubercle,  which  is  alter- 
nately nearer  and  farther  from  the  head,  and  that  the  neck  of  each  successive  rib  is 
alternately  long  and  short,  which  is  contrary  to  all  analogy  furnished  by  those  cold- 
blooded or  warm-blooded  Vertehrata  that  have  unquestionably  the  exogenous  pro- 
cess called  ^tubercle’  developed  from  the  true  neck  of  the  rib. 

When  the  partially  ossified  carapace  of  a young  tortoise  is  dried,  one  cannot  fail 
to  be  struck  with  the  difference  in  the  texture  and  external  suj-face  of  the  bones  which 
unquestionably  belong  to  the  endo-skeletal  vertebrae,  and  of  those  which,  notwith- 
standing their  connection  with  the  neural  spines  and  pleurapophyses,  are  developed 
in  the  fibrous  substance  of  the  corium.  These  nascent  ‘neural’  and  ‘costal  plates’ 
of  the  carapace  have  a granular  exterior  and  a coarse  spongy  texture,  whilst  the 
neural  arches  and  pleurapophyses  are  compact,  smooth,  and  with  a polished  external 
surface  : the  part  of  the  pleurapophysis  (PI.  XIII.  fig.  5,  d2 — d9)  which  passes  beneath 
and  is  attached  to  the  under  surface  of  the  ‘costal’  plate  {pi  i — pi  8),  contrasts 
strongly  with  that  superimposed  dermal  ossification. 

The  marginal  plates  {m  1 — m 1 l)present  the  same  rough,  coarse,  granular  character 
as  the  neural  and  costal  plates : they  are  in  no  way  connected  in  their  development 

* This  period,  in  its  relation  to  the  development  of  the  neural  arches  and  pleurapophyses,  corresponds  pre- 
cisely with  that  at  which  the  dermal  plates  of  the  Crocodile  begin  to  be  ossified. 

t Ueber  die  Entwickelung  der  Schildkrdten,  4to, 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


163 


with  the  pleurapophyses,  which  do  not  yet  reach  them  : their  ossification  has  been  go- 
verned by  the  presence  of  the  marginal  epidermal  scutes,  and,  as  in  the  case  of  the  cos- 
tal plates,  by  the  points  of  junction  of  contiguous  scutes  ; each  marginal  ossification  is 
accordingly  impressed  by  the  lines  indicating  the  junction  of  the  marginal  epidermal 
scutes  with  each  other  and,  in  the  case  of  the  middle  ones,  with  the  contiguous  scutes 
of  the  plastron.  The  number  of  the  marginal  plates  accords,  moreover,  with  that  of 
the  marginal  epidermal  scutella,  not  with  that  of  the  ribs, 

The  plastron  of  the  immature  Tortoise  (figs.  6 & 7)  presents  the  same  difference 
in  the  texture  and  surface  of  the  endo-skeletal  and  exo-skeletal  parts  of  the  incipient 
bones  as  does  the  carapace : the  triangular  entosternal  bone  (.s),  the  greater  part  of 
the  episternals  {es)  and  xiphisternals  {xs),  and  a smaller  proportion  of  the  hyosternals 
{hs)  and  hyposternals  {ips),  are  compact  bone  with  a smooth  shining  free  surface ; the 
greater  part  of  the  broad  hyosternal  and  hyposternal  plates,  the  entire  and  even  mar- 
gins of  which  are  encroaching  on  the  central  unossified  space  of  the  plastron,  are  sub- 
granular,  coarser  and  more  opake  than  the  slender  endo-skeletal  parts,  which  still 
retain  much  of  the  primitive  rib-like  form  they  presented  in  the  foetal  Chelone,  and 
are  seen  applied,  as  it  were,  to  the  inner  (upper)  surface  of  those  dermal  plates.  The 
median  extremities  of  the  true  endo-skeletal  parts  have  begun  to  expand,  and  to  shoot 
out  the  pointed  rays  of  tooth-like  processes  which  they  retain  in  the  Trionyces  and 
the  marine  Chelonia  (fig.  3).  From  the  flattened  and  expanded  inner  and  lower  end 
of  the  hyosternal  (fig.  7,  hs)  the  main  body  of  the  bone  arises  and  curves  upwards, 
outwards  and  forwards,  in  the  form  of  a long  and  slender  rib,  and  applies  itself  to  the 
inner  and  fore  part  of  the  first  elongated  pleurapophysis  of  the  carapace,  extending  as 
far  as  the  incipient  dermo-costal  plate ; the  rib-like  part  is  represented  detached  from 
the  rest  of  the  hyosternal  in  fig.  5,  hs.  As  the  inner  and  lower  toothed  border  of  the 
endo-skeletal  part  of  the  hyosternal  touches  the  outer  border  of  the  entosternal  bone, 
the  haemal  arch  of  the  first  segment  of  the  thoracic-abdominal  case  (second  vertebra 
of  the  back)  is  completed  independently  of  the  marginal  pieces  ; and,  in  point  of  fact, 
the  third  and  fourth  marginal  plates  (fig.  8,  m)  are  simply  applied  to  the  outer  side  of 
the  hyosternal  {h)  where  it  bends  upwards  to  join  the  first  long  pleurapophysis  {pi)  or 
rib  of  the  carapace.  The  most  obvious,  and,  I believe,  the  most  natural  explanation 
of  this  first  complete  segment  of  the  thoracic-abdominal  region  of  the  young  Tortoise, 
according  to  the  typical  vertebra,  and  the  composition  of  the  corresponding  segment  in 
the  nearest  allied  Vertehrata,  is — that  the  centrum  (PI.  XIII.  fig.  8,  c),  the  neural  arch 
(ns),  and  the  pleurapophysis  (j»/),are  the  parts  so  indicated  by  the  initial  letters  ; that 
the  hyosternals  (h)  are  the  hsemapophyses  (sternal  ribs  or  costal  cartilages),  and  the 
entosternum  {hs,s)  is  the  ‘haemal spine’  or  sternum  proper.  The  hyposternals  in  the 
young  Testudo  resemble  the  hyosternals,  but  are  shorter ; the  slender  rib-like  portion 
which  curves  upwards  and  outwards  applies  itself  to  the  back  part  of  the  extremity 
of  the  fifth  rib  of  the  carapace  {fig.b^ps),  almost  filling  the  interspace,  for  one-fourth 
of  its  length,  between  that  rib  and  the  next,  and  thus  again  forming  the  haemal  arch 

Y 2 


164  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


of  the  segment  without  the  intervention  or  aid  of  any  of  the  marginal  plates,  the 
seventh  of  these  being  simply  applied  to  the  outside  of  the  hyposternal,  where  its 
slender  elongated  extremity  bends  upwards  to  join  the  vertebral  rib : and  the  only 
incomplete  part  of  the  arch  is  the  unossified  median  space  between  the  lower  ex- 
panded and  dentated  ends  of  the  hyposternals,  between  which  the  entosternal,  or  true 
sternal  piece,  does  not  extend  backwards.  So  that  the  condition  of  this  fifth  segment 
of  the  thoracic-abdominal  box,  in  the  young  Tortoise,  repeats  that  of  a posterior  dor- 
sal segment  of  a mammal  or  crocodile,  in  which  the  cartilages  of  the  ribs,  or  abdo- 
minal ribs,  do  not  reach  the  sternum  ; and  the  Ornithorhynchus  offers  a special  re- 
semblance to  the  Tortoise  in  the  expansion  of  the  semiossified  hsemapophyses,  or 
cartilages  of  its  ‘false  ribs.’  The  xiphisternals,  viewed  in  like  manner  as  ‘hsem- 
apophyses’,  repeat  the  condition  of  those  abdominal  ones  in  the  Crocodile  and  Plesio- 
saur which  do  not  ascend  so  high  as  to  join  their  pleurapophyses  or  vertebral  ribs. 
The  difference  between  the  endo-skeletal  and  exo-skeletal  portions  of  these  elements 
of  the  plastron  is  as  plain,  and  the  contrast,  indeed,  is  almost  as  great,  in  the  young 
Tortoise  as  in  the  adult  Trionyx,  where  the  superadded  ossification,  at  the  expense 
of  the  dermal  system,  is  characterized  by  the  vermicular  or  punctate  character  of  the 
exterior  surface,  a character  common  to  the  dermal  ossified  plates  in  the  Reptilia, 
especially  of  the  closely-allied  Crocodilian  order  . 

The  main  purpose  of  the  augmentation  of  the  ordinary  vertebral  elements  in  the 
thoracic-abdominal  region  of  the  Chelonia,  by  the  extension  of  ossification  from  them 
into  the  corium,  and  the  consequent  connation  with  those  elements  of  dermal  bony 

* The  distinction  between  the  exo-skeletal  and  endo-skeletal  parts  of  the  plastron  is  so  well-marked  in  the 
Trionyx,  that  the  true  explanation  of  the  structure  has  forced  itself,  as  it  were,  upon  the  authors  who  have 
given  the  most  unqualified  adhesion  to  the  Cuvierian  and  GeofFroyian  hypothesis.  “ II  est  plus  important  de 
rappeler  ici  les  caracteres  principaux — qui  distinguent  I’ordre  des  Tortues  des  trois  groupes  d’animaux  ranges 
dans  cette  meme  classe  des  Reptiles ; d’abord  de  tons  les  autres  genres  par  la  structure  de  leur  squelette,  dont 
les  pieces  qui  constituent  le  tronc  sont  exterieures.  Les  vertebres  du  dos,  des  lomhes  et  du  bassin  etant  sou- 
dees  et  solidement  articulees,  non  seulement  entre  elles,  mais  avec  les  cotes  et  quelquefois  le  sternum,  par  de 
veritables  sutures,  ou  unies  par  cette  sorte  d’engrenage  que  I’on  nomme  synarthrose  •,  le  tout  forme  ainsi  une 
sorte  de  boite, — une  ‘carapace’ !— La  partie  inferieure  du  corps  est  egalement  protegee  par  des  pibces  osseuses, 
correspondantes  a un  sternum,  dont  I’ensemble  porte  le  nom  de  ‘plastron.’  ” — Dumeril  and  Bibron,  Erpeto- 
logie  Generate,  8vo,  tom.  i.  p.  349,  1834. 

The  description  of  the  carapace  of  a species  of  Trionyx  is  as  follows  : — “ Cette  esp^ce  et  la  suivante  sont  les 
seules  ou  I’on  ne  compte  sur  le  disque  de  la  carapace  que  sept  callosities  costales  de  chaque  cote  d’  I’epine  dor- 
sale,  encore  que  ces  deux  especes  aient  reellement  huit  paires  de  cotes  comme  tous  les  autres  Gymnopodes. 
Cela  vient  de  ce  que  chez  le  Gymnopode  spinif^re  et  chez  le  Gymnopode  mutique  il  n’existe  qu’une  seule  cai- 
losite  pour  les  deux  dernieres  cotes  de  chaque  cote,  tandis  que  dans  les  autres  Gymnopodes  les  seize  prolonge- 
mens  costaux  ont  chacun  leur  callosite.”  The  part  here  denominated  ‘callosity’  is  the  connate  dermal  bone 
which  is  described  in  this  memoir  as  the  ‘ costal  plate  ’ ; but  it  is  not  more  distinct  in  its  mode  of  development, 
nor  less  connate  with  the  subjacent  rib  in  those  Trionyces,  which  MM.  Dumeril  and  Bibron  call  ‘Gymnopodes,’ 
than  it  is  in  the  ordinary  Tortoises,  Terrapenes  and  Turtles  : only  the  superficial  character  of  the  superadded 
part  is  more  distinct  in  the  Trionyces : but  it  failed  to  draw  the  attention  of  the  distinguished  French  erpeto- 
logists  to  a reconsideration  of  the  homologies  of  the  carapace  which  they  had  adopted. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


165 


plates,  being  the  formation  of  a strong  defensive  abode,  although  the  existence  of  the 
cuticular  scutes,  rather  than  of  the  parts  of  the  endo-skeleton,  determines  the  com- 
mencement of  the  ossification  in  the  Tortoises,  yet  such  ossification  begins  and  pro- 
ceeds in  the  dorsal  and  sternal  integument  of  those  Chelonia,  e.  g.  Trionyx  and  Sphar- 
gis,  that  have  no  cuticular  scutella,  but  a soft,  uniform  and  lubricous  integument. 
The  influence,  however,  of  this  modification  of  the  cuticular  system  on  parts  regarded 
as  homologous  with  endo-skeletal  elements  in  the  ordinary  Chelonia,  is  strikingly 
manifested,  in  the  condition  of  the  marginal  plates  and  the  variable  proportions  and 
even  in  the  number  of  the  ossified  parts  of  the  plastron,  as  e.g.  in  that  of  the  Trionyx 
granosus  {Cryptopus,  D.  & B.),  in  which  a single  dermal  bony  plate  extends  over 
the  rudimentary  heemapophyses  called  hyosternals  and  hyposternals  on  each  side. 
The  cartilaginous  matrix  in  the  substance  of  the  qorium  forming  the  margin  of  the 
carapace  of  Sphargis  and  Trionyx,  receiving  no  stimulus  from  the  presence  of  mar- 
ginal scutella,  is  found  to  contain  either  mere  scattered  granules  of  ossific  matter, 
as,  €.  g.  in  the  Trionyces  forming  the  genus  Gymnopus  of  Dumeril  and  Bibron  ; or 
centres  of  ossification  are  established,  as  at  the  posterior  part  of  the  limb  of  the  cara- 
pace in  the  species  of  Cryptopus,  D.  & B.,  which  have  no  relation  whatever  with  the 
presence,  number  or  position  of  the  vertebral  ribs ; and  in  these  conditions  of  the 
border  of  the  carapace  we  perceive  a greater  or  less  retention  of  the  embryonic  cha- 
racter noticed  in  the  genus  Chelone. 

Summary. — The  conclusions  as  to  the  homologies  of  the  Chelonian  carapace  and 
plastron  to  which  I have  arrived  from  the  observations  above  recorded  and  other  de- 
tails with  which  it  has  not  been  deemed  necessary  to  encumber  this  communication, 
are  as  follow : — 

1st.  The  centrum  and  the  neural  arch  supporting  the  neural  plate  are  parts  the 
homologies  of  which  admit  of  no  question,  and  have  given  rise  to  none ; but  the 
neural  plate  itself  is  a dermal  bone  homologous  with  the  median  dermal  scutes  of 
the  Crocodile’s  back-shield,  but  connate  in  some  of  the  dorsal  segments  with  the  true 
neural  spine  in  the  Chelonia. 

2nd.  Only  the  free  proximal  and  distal  extremities  of  the  costal  plate  and  the  nar- 
row smooth  prominent  tract  * continued  from  the  one  end  to  the  other  along  the 
under  part  of  the  plate,  represent  the  ‘ pleurapophysis ’ or  vertebral  rib;  and  this 
rib  is  accordingly  simple,  as  in  other  reptiles  with  a tripartite  heart : the  external 
expanded  portion  which  joins  the  neural  plate  is  a dermal  bone  homologous  with 
the  medio-lateral  dermal  scutes  in  the  Crocodiles,  but  connate  with  the  pleurapo- 
physis in  the  Chelonia. 

3rd.  The  marginal  plates  are  wholly  dermal  scutes;  and  even  on  the  hypothesis 
that  any  of  them,  such  for  example  as  are  penetrated  by  the  free  ends  of  the  pleur- 
apophyses,  belong  to  the  endo-skeleton,  yet  these  answer  rather  to  the  accessory  in- 

* This  part  is  well  shown  in  the  view  of  the  inner  surface  of  the  carapace  of  the  ‘ Water-Tortoise,’  which 
Cheselden  gives  in  the  beautiful  plate  facing  the  3fd  Chapter  of  his  magnificent  ' Osteographia,’  fol.  1733. 


166  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


tervening  pieces  between  the  pleurapophyses  and  haeniapophyses  of  the  Crocodilian 
thorax* * * §,  than  to  the  hsemapophyses  in  their  totality. 

4th.  The  parial  or  lateral  parts  of  the  plastron,  more  especially  the  hyosternals  and 
hyposternals,  are  the  true  ‘ hsemapophyses’;  but  in  connation  with  dermal  bony  plates 
to  which  their  characteristic  breadth,  especially  in  the  land  and  freshwater  Chelo- 
nians,  is  chiefly  due.  The  entosternal,  and  perhaps  the  episternals,  which  repeat  the 
transverse  bar  of  the  T-shaped  sternum  in  Lacertia  and  Monotremata,  are  the  sole 
parts  of  the  plastron  which  can  be  referred  to  the  ‘ sternum  ’ in  special  homology  and 
to  the  ‘ hsemal  spine  ’ of  the  typical  vertebra  in  general  homology. 

Supplement. 

The  justly-merited  reputation  of  Prof.  Rathke  as  an  embryologist,  and  the  fact 
of  his  having  deduced  his  views  of  the  mixed  nature  of  the  thoracic-abdominal  part 
of  the  skeleton  of  the  Chelonian  Reptiles  from  observation  of  its  development,  equally 
demand  that  his  conclusions  should  not  be  abandoned  without  special  grounds  being- 
assigned.  Rathke  concludes,  as  has  been  before  stated,  that  the  carapace  belongs  to 
the  endo-skeleton  exclusively'!',  and  the  plastron  as  exclusively  to  the  exo-skeleton 

With  regard  to  the  carapace,  he  says,  “ The  spinons  processes  are  already  deve- 
loped from  the  second  to  the  eighth  dorsal  vertebr2e  before  the  exclusion  of  the  em- 
bryo,   they  remain  pretty  short,  but  contrary  to  the  general  laws  of  development 

of  the  vertebrate  animals,  they  grow  so  much  in  breadth,  that  they  form,  after  their 
ossification,  a series  of  horizontal  plates  of  moderate  size§.”  He  also  takes  occasion 
to  confute  the  assertions  of  Carus,  Wagner  and  Peters,  that  these  plates  are  first 
developed  independently  in  the  derm  and  afterwards  coalesce  with  the  spines  of  the 
subjacent  vertebrae.  My  observations  concur  with  those  of  Rathke  in  regard  to  the 
fact  that  the  neural  plates,  answering  to  the  eight  vertebrae  of  the  carapace,  are  not 
developed  independently  of  the  neural  spines,  but  are  connate  with,  or  ossified  con- 
tinuously from  them  [].  Nevertheless  the  position  of  the  pre-existing  fibro-cartilaginous 
matrix,  and  the  distinctive  character  of  the  resulting  ossification,  appear  to  me  to  be 
stronger  grounds  for  determining  their  dermal  homology,  than  the  mere  fact  of  their 
connation  in  opposition  to  that  view.  The  radius  and  ulna  of  the  Frog  are  not  only 
confluent  but  connate ; i.  e.  they  are  progressively  or  continuously  ossified  from  a 

* These  are  well  shown  by  Cheselden  in  the  side  view  of  the  skeleton  of  the  Crocodile,  which  forms  the 
vignette  of  chapter  hi,,  op.  cit.  They  are  not  noticed  in  either  of  the  editions  of  Cuvier’s  ‘ Ossemens  Fossiles,’ 
or  of  the  ‘ Lecons  d’Anatomie  Comparde,’  and  are  therefore  unnoticed  in  most  of  our  English  compilations  of 

Comparative  Anatomy. 

t Ueber  die  Entwickelung  der  Schildkroten.  4to,  p.  105.  t Ik.  p.  122—129. 

§ Loc.  cit.,  and  Annales  des  Sciences  Naturelles,  Mars,  1846. 

11  At  least  in  the  Testudo  and  Chelone.  In  some  Trionyces  ossification  extends  into  the  eighth  neural  plate 
from  the  median  ends  of  the  eighth  costal  plates,  and  in  a new  species  which  I have  called  Trionyx  planus  the 
same  modification  supersedes  the  seventh  neural  plate.  These  varieties  are  very  significative  of  the  dermal  cha- 
racter of  the  neural  plates. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


167 


common  centre,  yet  their  essential  homologies  are  neither  thereby  destroyed  nor 
much  masked. 

The  unimportant,  one  might  almost  say  accidental  character  of  connation,  in  re- 
gard to  the  neural  plates  of  the  carapace,  is  shown  by  its  absence  in  at  least  one- 
fourth  of  the  series  of  those  plates.  Rathke  admits  that  the  first  or  nuchal  plate, 
the  ninth,  tenth,  eleventh  and  twelfth  of  the  median  series  of  plates  of  the  carapace 
are  developed  from  independent  centres  in  the  substance  of  the  corium,  and  are  there- 
fore dermal  bones.  Now  it  is  indisputable  that  these  are  the  homotypes  or  serial 
homologues  of  the  second  to  the  eighth  of  the  same  median  series  of  plates.  The 
mere  circumstance  of  connation  of  these  plates  with  the  closely  subjacent  vertebrse 
cannot  make  so  essential  a difference  as  is  implied  by  their  classification  in  a distinct 
skeleton-system  from  that  to  which  their  homotypes  are  admitted  to  belong. 

With  regard  to  the  ‘costal  plates,’  M.  Rathke,  after  rightly  stating  that  “all,  or 
nearly  all,  of  the  ribs  of  the  trunk-vertebrae  are  cylindrical  until  the  exclusion  of  the 

embryo,”  proceeds  to  say,  “ they  then  begin  to  increase  in  breadth  ; this  increase 

commences  at  the  place  where  the  neck  of  the  rib  joins  the  body  of  the  rib,  and 
thence  advances  more  or  less  towards  the  (distal)  extremity:  it  becomes  so  consider- 
able, that  the  bodies  of  all  the  ribs,  by  reason  of  the  complete  absence  of  intercostal 
muscles,  come  into  contact  on  each  side,  either  through  their  entire  length,  as  in  the 
genera  Emys,  Terrapene,  Testudo,  Trionyx,  or  nearly  their  whole  length,  as  in  Che- 
lone^." 

The  author  appears  to  have  traced,  with  great  industry  and  perseverance,  the  de- 
velopment of  the  carapace  in  each  of  the  genera  which  he  cites  in  the  above  quota- 
tion : but  the  very  general  terms  in  which  such  development  is  described  might  have 
been  suggested  by  a mere  comparison  of  its  results  as  they  are  manifested  in  the  adult 
carapaces,  except  that  in  no  species  of  Trionyx  are  the  ribs  united  throughout  their 
entire  length : the  extremity  of  the  actual  rib  projects  from  the  peripheral  end  of  the 
superincumbent  costal  plate,  even  in  the  oldest  specimens.  M.  Rathke  proceeds: — 
“ Soon  after  the  eight  pairs  of  ribs  have  begun  to  expand  a process  is  sent  off  from 
above  near  the  spinal  column,  which  by  its  growth  overlaps  the  few  and  slender 
dorsal  muscles,  and  unites  with  the  spinous  process  of  the  vertebrae -i-.”  Such  a de- 
scription of  the  development  of  the  costal  plates  could  be  suggested,  I believe,  only 
by  observation  of  a tolerably  young  specimen  of  Chelone  or  Emys.  There  is  no 
mention  of  the  development  of  the  costal  plates  in  the  Tortoise  {Testudo)  by  super- 
position of  osseous  matter  upon  the  rib,  the  supporting  part  of  which  rib  retains  its 
normal  form  without  expanding : there  is  no  allusion  to  the  alternately  varying  posi- 
tion of  the  superimposed  dermal  ossification  in  regard  to  the  rib  supporting  it,  nor  to 
the  relation  of  the  incipient  costal  plates  to  the  angles  of  union  of  the  epidermal 
scutes.  Perhaps  these  facts,  so  important  in  guiding  us  to  the  right  homology  of  the 
costal  plates  of  the  carapace,  were  manifested  in  the  young  Tortoises  examined  by 
Prof.  Rathke,  though  he  has  not  described  them  : and  yet  it  would  be  unfair,  without 
* Loc.  cit.  Loc,  cit. 


168  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


stronger  evidence,  to  suppose  such  defects  in  his  description.  They  are,  however, 
plainly  demonstrated  in  my  preparations,  and  are  accurately  represented  in  the 
figures  4 and  5 of  Plate  XIII.  I entirely  concur  with  Prof.  Rathke  in  regarding 
the  marginal  plates  as  dermal  bones : in  every  particular  of  developmental  character 
they  agree  with  one-fourth  of  the  median  series  of  bony  plates  of  the  carapace  (neural 
plates);  and  in  every  respect,  save  connation  with  endo-skeletal  bones,  they  agree 
with  the  rest  of  the  median  series  and  with  all  the  costal  series  of  bony  plates  of  the 

f 

carapace. 

Finally,  there  remains  for  consideration  Prof.  Rathke’s  peculiar  hypothesis  of  the 
nature  of  the  plastron. 

“ The  development  of  the  plastron,”  he  says,  “ takes  place  later  than  in  Birds  and 
Mammals : the  cartilaginous  basis  consists  of  two  pairs  of  very  narrow  and  thin  car- 
tilages, one  in  front  and  the  other  behind  the  umbilical  aperture : there  is  likewise 
formed  a fifth  azygous  piece  in  most  Chelonians”  (he  excepts  with  a doubt), 

“ between  the  two  anterior  parial  pieces  ....  Subsequently  there  are  developed  in 
these  different  cartilages,  more  numerous  osseous  pieces,  ordinarily,  or  perhaps  always, 
nine  in  number.  Their  respective  size  varies  greatly,  according  to  the  different  spe- 
cies of  Chelonians ; for  either  they  grow  in  such  a way,  the  one  in  front  of  the  other, 
that  they  meet  by  their  corresponding  borders  in  their  whole  length,  so  as  to  consti- 
tute a continuous  plastron,  or  their  growth  is  more  restricted,  and  then  they  form  a 
plastron  open  in  the  middle ; or  they  constitute  merely  a narrow  ring,  as  is  probably 
the  case  in  the  Sphargis*." 

He  alludes  to  other  modifications  of  growth,  which  might  equally  have  been  sug- 
gested by  the  known  varieties  of  the  plastron  in  the  adults  of  the  different  genera  and 
species  of  Chelonia ; e.g.  where  it  extends  forwards  beyond  the  neck,  and  backwards 
beyond  the  tail,  which  he  thinks  may  probably  depend  upon  the  presence  of  an  infe- 
rior fold  of  chorion  existing  in  front  of  the  fore-feet,  and  of  another  inferior  fold  be- 
hind the  hind-feet : although  he  admits  that  where,  as  in  the  Trionyx,  such  folds 
occur,  they  are  not  occupied  by  the  plastron,  which  fact  invalidates  the  hypothesis. 

My  observations  do  not  agree  with  those  of  Rathke,  which  have  led  him  to  ascribe 
the  eight  parial  pieces  of  the  plastron  to  the  development  of  as  numerous  osseous 
pieces  in  the  two  pairs  of  primitive  slender  cartilages.  I find  no  other  ossification 
set  up  on  the  anterior  pair  of  those  cartilages  than  that  which  results  in  the  forma- 
tion of  the  hyosternals  ; and  no  other  in  the  posterior  pair  than  that  which  results  in 
the  formation  of  the  hyposternals.  The  episternals  unquestionably  have  independent 
cartilages,  and  so  I believe  have  the  xiphisternals,  though  I have  failed  to  get  so 
clear  a demonstration  of  the  latter. 

The  primitive  cartilages  of  the  true  sternum  (entosternal)  and  the  thoracic-abdo- 
minal hsemapophyses  (hyosternals  and  hyposternals)  are  distinct  from,  and  deeper- 
seated  than,  the  thin  stratum  of  cartilage-cells  which  pervades  and  thickens  the  ven- 
tral fibrous  integument.  I am  unwilling  to  suppose  that  Rathke  could  have  ever  wit- 

* Loc.  cit. 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


169 


nessed  the  marked  distinction  between  the  ossification  of  these  endo-skeletal  parts  and 
the  superadded  dermal  ossified  layer,  and  have  made  no  mention  of  it.  He,  in  fact, 
maintains  his  opinion,  that  the  plastron  is  nothing  else  but  a part  of  the  dermo- 
skeleton,  and  that  it  has  nothing  in  common,  in  an  anatomical  point  of  view,  with 
the  sternum  of  other  animals*,’’  fl^us  diverging  to  an  opposite  extreme  from  that  of 
the  GeoflTroyan  hypothesis,  although  rather  by  arguments  drawn  from  the  relative 
position  of  other  parts  of  the  skeleton  and  from  Comparative  Anatomy  than  from  the 
actual  phenomena  of  the  development  of  the  plastron. 

If  the  plastron  of  the  Chelonia  were  the  homologue  of  the  sternum  in  other 
Vertebrates,”  says  Rathke,  one  must  also  admit  that  the  bones  composing  the 
shoulder  and  pelvis  are  situated  in  a manner  entirely  contrary  to  the  general  dispo- 
sition of  those  parts  in  other  animals.”  But  that  remark  would  equally  apply  as  an 
argument  against  the  carapace  being  homologous  with  the  vertebrae  and  ribs,  as 
Rathke  contends  it  to  be.  It  appears  to  me,  however,  that  the  peculiarly  advanced 
position  of  the  scapular  arch  in  the  embryo  Chelonia,  and,  at  its  first  appearance  in 
all  other  Vertebrates,  in  relation  to  the  thoracic  haemal  arches, — a transitory  relative 
position  so  beautifully  explained  by  the  recognition  of  the  scapular  arch  as  the  haemal 
arch  of  the  occipital  vertebra — equally  explains  and  removes  the  anomaly  of  its  posi- 
tion in  regard  to  the  plastron  of  the  adult  Chelonians  as  in  regard  to  the  carapace. 
In  both  instances  the  Chelonian  peculiarity  or  anomaly,  in  the  relative  position  of 
the  bones  of  the  shoulder,  is  due  to  the  retrogradation  of  the  scapular  arch  and  the 
concomitant  expansion  of  certain  succeeding  haemal  arches ; as,  for  example,  that 
formed  by  the  second  pair  of  dorsal  ribs  above,  and  by  the  episternal  and  hyosternal 
bones  below ; the  one  extending  above  the  arch  as  a roof,  the  other  beneath  it  as  a 
floor.  The  discordance  of  the  relations  of  the  scapular  and  pelvic  arches  of  the 
Chelonians  with  those  in  other  Vertebrates  no  more  necessitates  the  assumption  that 
all  the  plastron  belongs  to  the  dermo-skeleton,  than  that  all  the  carapace  does. 

With  regard,  indeed,  to  the  relations  of  the  pelvis  to  the  plastron,  whilst  we  should 
look  amongst  other  Vertebrates,  in  vain,  for  instances  in  which  the  ossified  exo- 
skeleton is  developed  beneath  it,  as  Rathke  supposes  it  to  be  in  the  Chelonia  (fig.  8, 
in  which  ps  and  xs  are  referred  by  that  author  to  the  exo-skeleton-f-),  we  have  not  far 

* Loc.  cit. 

t In  the  figures  8 and  9 hh  are  the  hsemapophyses  or  abdominal  ribs,  specified  in  the  Chelonia  as  hs  hyoster- 
nals,  hypostemals,  and  xs  xiphisternals : 62  is  the  modified  pleurapophysis  called  ‘ilium’;  63  and  64,  the 
modified  haemapophyses,  called  respectively  ‘ ischium  ’ and  ‘ pubis  ’ ; 65,  femur;  66,  tibia;  67,  fibula;  68,  tar- 
sus ; 69,  metatarsus  and  phalanges. 

In  a fossil  iJmys  from  Sheppey,  described  by  Professor  Bell,  Sec.R.S.,  in  our  joint  Monograph  on  the  Fossil 
Chelonia  of  the  London  Clay,  an  intercalated  piece  is  wedged  in  between  the  outer  part  of  the  interspace  of 
the  hyosternal  and  hyposternal  on  each  side,  like  the  dismemberments  of  the  abdominal  ribs  at  the  outer  part 
of  that  group  of  bones  in  the  Plesiosaurus  : and  in  another  fossil  Emydian  from  the  same  formation  and  loca- 
lity, an  intercalated  bony  piece  extends  across  between  the  hyosternal  and  hyposternal  on  each  side  of  the 
plastron.  See  Description  of  Platemys  Bullockii,  in  my  Report  on  British  Fossil  Reptiles,  Report  of  the  British 
Association,  1841,  p.  164. 

MDCCCXLIX.  Z 


170  PROFESSOR  OWEN  ON  THE  DEVELOPMENT  AND  HOMOLOGIES  OF  THE 


to  seek  for  examples  in  which  ordinary  elements  of  the  endo-skeleton  are  extended 
between  the  pelvis  and  the  ventral  integuments.  Not  to  speak  of  the  Plesiosaurus 
(fig.  7)5  in  which  the  underlapping  of  the  pubic-bones  64,  by  the  abdominal  ribs  Qi), 
might  be  due  to  displacement  of  the  fossilized  parts ; the  Puffins  {Fratercula),  the 
Guillemots  {Uria)  (fig.  9),  and  other  common  sea-birds  of  our  coasts  give  the  examples 
of  the  sternum  prolonged  backwards  to  beyond  the  vertical  line  traversing  the  aceta- 
bulum ; whilst  the  hsernapophyses  (Ji,  Ji,  ossified  cartilages)  of  the  three  or  four  pos- 
terior ribs  extend  backwards  beyond  or  as  far  as  the  most  backwardly  prolonged 
parts  of  the  pelvis  (ea,  64),  exactly  in  the  relative 
position  which  the  xiphisternals  and  hyposter- 
nals  bear  to  the  pelvis  of  the  Chelonia. 

In  this  comparison  it  is  interesting  also  to 
discern  the  harmony  which  pervades  the  same 
vertebral  elements  in  the  characteristic  forms 
which  they  assume  in  the  same  species.  In  the 
sea-birds  cited  the  ossa  pubis  (64),  or  the  hsem- 
apophyses  of  the  pelvic  arch,  are  long  and  slen- 
der, like  the  costal  hsernapophyses  {h)  beneath 
them : in  the  Chelonian  reptiles  the  ossa  pubis 
(64)  are  broad  and  expanded,  like  the  costal  hse- 
mapophyses  {ps,  xs),  which  equally  intervene 
between  them  and  the  ventral  integument. 

Nature  is  ever  liberal  in  rewarding  with  the 
perception  of  such  harmonies  whoever  patiently 
investigates  and  rightly  comprehends  her  ar- 

. Belations  of  thoracic  to  pelvic  hsernapophyses,  Plesiosaurus. 

rangements. 


Fig.  8. 


Relations  of  thoracic  to  pelvic  hsernapophyses,  Chelonian. 


Fig.  9. 


Relations  of  thoracic  to  pelvic  hsernapophyses.  Bird  {Uria  Troile). 


Bnl  7;v,/«,JyII)CCCXLiX,/'/ff//.  Xllf.^.  r/j. 


A/.  Liu, 


Tif  ],T 


rig. 2. 


in  (1 


in  o 


77/ 7 


in  /U 


rnS 


in  /) 


.Br.. 


in') 


1 


CARAPACE  AND  PLASTRON  OF  THE  CHELONIAN  REPTILES. 


171 


Description  of  the  Plate. 

PLATE  XIII. 

(All  the  figui’es  are  of  the  natural  size.) 

Fig'.  1.  Embryo  Turtle  {Chelone  Mijdaa). 

1 a.  Ossified  parts  of  its  carapace. 

Fig-.  2.  Side  view  of  the  same  embryo. 

2 a.  Side  view  of  the  ossified  parts  of  its  carapace. 

Fig.  3.  Front  view  of  the  same  embryo. 

3 a.  Ossified  rudiments  of  the  plastron. 

Fig.  4.  External  surface  of  the  incipient  carapace  of  a young  Tortoise  {Testiido 
indica). 

Fig.  5.  Internal  view  of  the  same  carapace. 

Fig.  6.  External  surface  of  the  plastron  of  the  same  young  Tortoise. 

Fig.  7-  Internal  view  of  the  same  plastron. 

Fig.  8.  Ideal  section  of  the  same  carapace  and  plastron. 

The  letters  and  figures  are  explained  in  the  text. 


Phu.ntxn*.  M^c^cxLlX■/»^x^v■ 


proTtA»/i) 


WnlOTll 


in  tUe 

AT]LANTIC^  OCEAX 

between  the 

f>0  ^/l (W/  -/aZ/Zf/f/e, 


y^t  ; •//  iZiO. 


Zimt  Coiofif/  EZumii  Sa/mie.  StrZZ.S.  T 


Ecut  Declin.  has  the  sign  - prefixed. 


Kn}^«v*»J  Iw  .1^  < U'ilWf 


‘r  ■ 


Ol 


" . • ■« 


■■■  '■' 


■ \\  ■ 


:-  ■-  .A'’'?. 


iyyz*-  •=•4/'  ^ , ,/ 

■'‘'tOo.'V'  ■ y 


....  ' ■ / 

A'  ' ■ ^v' 

. '■  yy  •■'  V,  ;<  ■ . 

'■y-  ''■'■‘f;'  ■ 


■ ■ -• 
■ ■ ■•*  ..-■wv’ 

.X 


' ■r'  '.  ' .^.'(%'s-Xf  -'''  ^''  ■' 


— -.  — T-;  ; '■  ' ■,?'o  ? / 


■ 


y' 


y-. 


/ 


■M  / 

// 


4 


PHILOSOPHICAL  TRANSACTIONS. 


XII.  Contributions  to  Terrestrial  Magnetism. — No.  IX. 
By  Lieut. -Colonel  Edward  Sabine,  R.A.,  For.  Sec.  R.S. 


Received  May  24, — Read  June  21,  1849. 


Containing  a Map  of  the  Magnetic  Declination  for  1 840  in  the  Atlantic  Ocean  between 
the  parallels  of  60°  North  and  60°  South  Latitude. 

In  compliance  with  repeated  representations  from  the  Hydrographer  of  the  Admi- 
ralty, that  a correct  map  of  the  magnetic  Declination  over  the  Atlantic  Ocean 
corresponding  to  the  present  epoch  was  most  urgently  required  for  the  purposes  of 
navigation,  I have  deemed  it  proper, — partly  on  account  of  the  importance  of  the 
object  itself,  and  partly  in  acknowledgement  of  the  claim  which  the  practieal  wants 
of  those  who  traverse  the  seas  have  on  that  physical  science  which  they  so  much 
contribute  to  advance, — to  suspend  the  progress  of  the  publication  of  the  observations 
made  at  the  colonial  magnetical  and  meteorological  observatories,  until  in  compli- 
ance with  the  wishes  of  the  Admiralty  a Declination  map  of  the  Atlantic  has  been 
completed.  I have  endeavoured  at  the  same  time  so  to  conduct  and  arrange  the 
preliminary  investigation,  that  it  may  form  a fitting  part  of  the  magnetic  survey  of 
the  globe,  which  is  designed  to  be  comprehended  in  the  series  of  Magnetic  Contribu- 
tions, of  which  the  first  eight  numbers  have  been  honoured  with  a place  in  the  Philo- 
sophical Transactions. 

The  limits  which  have  been  taken  for  the  map,  in  respect  to  latitude,  are  the  parallels 
of  60°  north  and  60°  south.  The  number  of  distinct  determinations  within  those 
limits,  either  at  sea  or  on  adjacent  coasts  or  islands,  which  have  been  reduced  and 
coordinated,  amounts  to  1480.  Each  determination  is,  in  the  majority  of  cases,  a 
mean  result  of  several  distinct  and  independent  observations.  They  are  all  com- 
prised between  the  beginning  of  1828  and  the  end  of  1848;  the  commencement  of 
1840  being  taken  as  the  epoch  of  the  map;  and  each  determination  being  reduced 
to  that  epoch  by  the  rate  of  secular  change  derived  by  comparison  with  the  map  of 

MDCCCXLIX.  2 A 


174 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


the  Declination  in  1787,  published  by  M.  Hansteen  in  his  great  work,  Magnetismus 
der  Erde,  and  republished  by  myself  in  this  country  in  the  Reports  of  the  British 
Association  for  the  Advancement  of  Science  for  1834.  Of  the  determinations  made 
at  sea,  all  have  been  corrected  for  the  effect  of  the  ship’s  iron  when  observations  on 
which  the  corrections  must  depend  have  been  provided.  I have  discussed  those 
corrections  in  more  detail  and  at  greater  length  than  I might  otherwise  have  done, 
on  account  of  the  practical  importance  attaching  to  this  part  of  the  subject  since  the 
introduction  of  steam  navigation  and  the  increased  employment  of  iron  in  the  con- 
struction and  equipment  of  vessels ; and  in  the  hope  and  belief  that  the  discussion 
may  be  found  to  have  a practical  as  well  as  a theoretical  value. 

The  1480  determinations  reduced  and  corrected  for  epoch  are  arranged  in  a general 
Table  in  Zones,  each  zone  including  10°  of  latitude;  the  determinations  comprised 
in  each  zone  are  arranged  in  the  order  of  their  longitudes,  commencing  always  with 
the  most  westerly : they  are  all  likewise  inserted  in  the  map,  where  they  are  expressed 
in  degrees  and  decimals  of  a degree.  For  the  purpose  of  drawing  the  lines  of  decli- 
nation in  general  conformity  with  the  determinations,  the  latter  have  been  arranged 
in  groups,  each  group  having  its  mean  geographical  position  at  or  near  the  point  of 
intei’section  of  every  fifth  meridian  and  parallel,  (as  far  as  the  observations  would 
permit,)  counting  from  the  parallel  of  0°,  and  the  meridian  of  280°;  and  in  the  moi’e 
frequented  parts,  and  where  consequently  the  number  of  determinations  was  greatest, 
at  or  near  the  points  of  intersection  of  parallels  and  meridians  distant  only  2^  degrees 
from  each  other.  Each  group  contains  all  the  determinations  comprised  within 
equal  distances  of  latitude  and  equal  distances  of  longitude  on  either  side  of  the  point 
of  intersection ; the  distances  being  so  taken  that  the  number  of  determinations  con- 
stituting a group  should  be  generally  from  ten  to  twenty. 

If  the  mean  geographical  position  corresponding  to  the  determinations  in  a group 
diflfered  more  than  a few  minutes  from  the  latitude  or  longitude  of  the  desired  point 
of  intersection,  one  or  two  determinations  adjacent  to,  but  beyond  the  limit,  were 
taken  into  the  group,  or  one  or  two  pairs  of  determinations  within  the  limits  were 
combined  and  their  mean  taken  instead  of  the  separate  results.  This  was  done  for 
the  purpose  of  diminishing  the  amount  of  the  correction  to  be  applied  to  the  mean 
declination  of  the  group,  to  reduce  it  to  the  corresponding  value  of  the  declination 
at  the  point  of  intersection  itself.  The  factors  employed  in  making  that  reduction 
were  derived  from  the  map  itself.  The  values  of  the  declination  thus  obtained  at 
the  intersection  of  every  fifth  degree  of  latitude  and  longitude  (as  far  as  the  determi- 
nations permitted),  and  at  the  intersection  of  every  2^  degrees  in  the  more  frequented 
quarters,  have  been  regarded  as  elements  of  the  declination  lines ; and  these  lines 
have  been  drawn  in  accordance  with  the  elements  with  only  such  slight  deviations 
as  were  indispensable  to  preserve  an  interconformity  between  the  lines,  where  it  was 
evident  that  the  determinations  themselves  were  slightly  discordant.  The  values  of 
the  Declination  at  the  points  of  intersection  obtained  by  the  process  of  grouping  are 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


175 


collected  in  Table  VIIL,  and  are  also  exhibited  in  the  Map  in  larger  and  more  con- 
spicuous figures  than  those  which  represent  the  determinations  from  which  they  are 
severally  derived.  The  map  thus  contains,  first,  the  original  determinations  reduced 
to  the  mean  epoch  ; secondly,  the  elements,  or  mean  values  for  the  points  of  inter- 
section, derived  from  the  determinations ; and  thirdly,  the  lines  themselves  derived 
from  the  elements,  so  that  the  degree  of  accordance  of  the  elements  and  of  the  lines 
with  the  sources  from  whence  they  are  derived  may  be  everywhere  judged  of  by 
inspection. 

The  determinations  employed  in  this  Memoir  have  been  obtained  from  the  following 
sources : — 

(A.)  Sea  observations  uncorrected  for  the  effects  of  the  Ship's  Iron. 

1.  Observations  made  in  the  corvette  Krotkoi  by  Dr.  Adolph  Erman  in  her  home- 
ward voyage  from  Cape  Horn  to  Portsmouth  in  1830;  extracted  from  Erman’s  Reise 
urn  die  Erde. 

2.  Observations  made  on  board  the  Beagle,  Captain  Robert  FitzRoy,  on  her  out- 
ward passage  from  England  to  South  America  in  1831  and  1832,  and  whilst  on  the 
South  American  station,  east  of  Cape  Horn,  in  1833  and  1834  ; and  on  her  homeward 
passage  in  1836  from  the  Cape  of  Good  Hope  to  the  British  Channel;  extracted  from 
the  published  account  of  the  voyage. 

3.  Observations  made  on  board  the  corvette  La  Bonite,  Captain  Vaillant,  on  her 
outward  passage  from  Toulon  round  Cape  Horn  in  1836,  and  on  her  homeward 
passage  in  1837  from  the  Cape  of  Good  Hope  to  Brest ; extracted  from  the  published 
account  of  the  voyage. 

4.  Observations  made  on  board  the  frigate  La  Venus,  Captain  (since  Admiral)  Du 
Petit-Thouars,  in  her  outward  passage  from  France  round  Cape  Horn  in  1837,  and 
in  her  homeward  passage  in  1839  from  the  Cape  of  Good  Hope  to  Brest ; extracted 
from  the  published  account  of  the  voyage. 

5.  Observations  made  by  Captain  (since  Admiral)  Berard,  on  board  the  brig  Le 
Voltigeur  in  a voyage  in  1838  from  Toulon  to  Vera  Cruz,  and  from  thence  by  New 
York  to  Brest ; and  on  board  the  corvette  Le  Rhin,  on  her  outward  passage  from 
Toulon  to  the  Cape  of  Good  Hope  in  1842,  and  in  her  homeward  passage  from  Cape 
Horn  by  St.  Helena  to  Toulon  in  1846 ; from  a MS,  obligingly  communicated  to  me 
by  Captain  Duperrey,  Membre  de  ITnstitut. 

6.  Observations  made  on  board  La  Prevoyante  by  Captain  Jehenne,  on  a passage 
from  the  Cape  of  Good  Hope  by  St.  Helena  to  Cayenne  in  1842 ; extracted  from  the 
Annales  Maritimes  et  Coloniales  for  1843. 

7.  Observations  made  in  H.M.S.  Curagoa,  Captain  Sir  Thomas  Sabine  Pasley,  Bart,, 
whilst  on  the  South  American  station  in  1843  and  1844;  MSS. 


2 A 2 


176 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


(B.)  Sea  observations  corrected  for  the  effects  of  the  Ship’s  Iron. 

8.  Observations  made  on  board  H.M.S.  Erebus,  Captain  Sir  James  Clark  Ross, 
in  her  outward  passage  from  England  to  St.  Helena  and  the  Cape  of  Good  Hope  in 
1839  and  1840;  MSS. 

9.  Observations  made  on  board  H.M.S.  Thunder,  Captain  Edward  Barnett,  in  a 
passage  from  the  Bahama  Islands  to  the  British  Channel  in  1841  ; MSS. 

10.  Observations  made  on  board  H.M.  Ships  Erebus  and  Terror,  Captains  Sir  James 
Clark  Ross  and  F.  R.  M.  Crozier,  in  the  (Antarctic)  summer  of  1842-1843,  between 
Cape  Horn  and  the  Cape  of  Good  Hope ; MSS. 

11.  Observations  made  on  board  the  Prince  Regent  transport,  by  Captain  John 
Henry  Lefroy,  R.A.,  in  a passage  from  England  to  Quebec  in  1842;  MSS. 

12.  Observations  made  in  H.M.  hired  bark  Pagoda,  by  Lieut,  (since  Commander) 
T.  E,  L.  Moore,  R.N.,  and  Lieut,  (since  Captain)  Henry  Clerk,  R,A,,  in  a voyage 
from  the  Cape  of  Good  Hope  to  the  Antarctic  Circle  in  1845  ; extracted  from  the 
Philosophical  Transactions  for  1847- 

13.  Observations  made  on  board  H,M,S.  Philomel,  Captain  Bartholomew  J,  Suli- 
VAN,  in  a passage  from  Monte  Video  to  the  British  Channel  in  1846 ; MSS, 

14.  Observations  made  on  board  the  Hudson’s  Bay  Company  ship  Prince  Albert, 
by  Lieut,  (since  Commander)  T.  E.  L.  Moore,  in  a voyage  from  England  to  Moose 
Fort  in  Hudson’s  Bay  and  back,  in  1846 ; MSS. 

15.  Observations  made  on  board  H.M.S,  Rattlesnake,  Captain  Owen  Stanley,  in 
her  outward  passage  from  the  British  Channel  to  the  Cape  of  Good  Hope  in  1846  and 
1847;  MSS. 

(C.)  Land  observations  on  the  coasts  and  islands  of  the  Atlantic. 

16.  Observations  at  several  points  of  the  South  American  coast  and  of  the  Falk- 
land Islands  in  1832,  1833  and  1834,  by  Captain  Robert  FitzRoy,  R.N.  ; extracted 
from  the  Voyage  of  the  Beagle. 

17-  Observations  at  several  points  of  the  Falkland  Islands  and  on  the  South  Ame- 
rican coast  and  its  vicinity,  between  1843  and  1846,  by  Captain  Bartholomew  J.  Su- 
LiVAN,  R.N. ; MSS. 

18.  Observations  during  the  voyage  of  the  Chanticleer,  between  1828  and  1831  at 
several  stations  on  the  coast  of  the  Atlantic,  by  Captain  Henry  Foster  and  Captain 
Horatio  Austin,  R.N. ; MSS. 

19.  Observations  at  various  points  of  the  coasts  adjacent  to  the  Gulf  and  River 
St.  Lawrence  in  the  years  1828  to  1848,  by  Captain  H.  W.  Bayfield,  R.N, ; MSS. 

20.  Observations  on  several  points  of  the  Feroe  and  Shetland  Islands  and  of  the 
Hebrides  in  1831,  and  on  the  West  Coast  of  Africa  in  1836  and  1838,  and  in  the 
Western  Islands  in  1843  and  1844,  by  Captain  A.  Vidal,  R.N. ; MSS. 

21.  Observations  made  at  several  stations  on  the  islands  and  coasts  of  the  Atlantic 
and  Caribbean  Sea,  from  1837  to  1840,  by  Captain  A.  Milne,  R.N. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


177 


22.  Observations  at  several  stations  in  Guiana  in  1842  and  1843,  by  Sir  Robert 
ScHOMBURGK,  employed  as  Boundary  Commissioner;  MSS. 

23.  Observations  at  several  stations  in  the  vicinity  of  the  River  St.  Lawrence  in 
1842,  by  Captain  J.  H.  Lefroy,  R.A.  ; MSS. 

24.  Observations  at  several  stations  in  the  British  Islands  in  1838,  by  Captain 
Sir  James  Clark  Ross,  R.N.  ; MSS. 

25.  Observations  (with  a transportable  Declinometer)  at  stations  on  the  North 
Coast  of  Scotland,  by  Commander  H.  C.  Otter,  R.K.  ; MSS. 

26.  Observations  at  several  points  of  the  coast  of  Western  Africa  in  1845  and  1846, 
by  Captain  H.  M.  Denham,  R.N. ; MSS. 

27.  Observations  at  several  stations  on  the  coast  of  the  United  States  of  America 
in  the  years  1844  to  1846,  in  the  progress  of  the  United  States  Coast  Survey;  extracted 
from  the  published  Charts  of  the  Survey. 

28.  Observations  (with  a transportable  Declinometer)  in  1848  at  stations  in  the 
Gulf  of  St.  Lawrence,  by  Dr.  Kelly,  R.N. ; MSS. 

29.  Declinations  determined  at  the  observatories  of  Algiers,  Brussels,  Cape  of  Good 
Hope,  Christiania,  Dublin,  Greenwich,  Makerstoun,  Paris,  St.  Helena,  and  Toronto  in 
Canada ; extracted  from  official  sources : and  at  Rio  Janeiro  by  Herr  von  Helm- 
reicher  in  1845  with  a transportable  Magnetometer;  MSS. 

30.  Declinations  observed  by  Lieut.-Colonel  Graham  of  the  United  States  Topo- 
graphical Engineers,  and  by  other  officers  of  that  corps,  and  surveyors  employed 
under  his  direction  in  the  Commission  for  determining  the  boundary  between  the 
United  States  and  the  British  Possessions  in  North  America.  I am  indebted  to  the 
liberality  and  kindness  of  Lieut.-Colonel  Graham  for  the  communication  of  the  ma- 
nuscript of  these  valuable  observations,  which  connect  the  determinations  of  Captains 
Bayfield,  R.N.,  and  Lefroy,  R.A.  in  Canada,  with  those  of  the  United  States  Coast 
Survey  in  New  York  and  the  more  southern  states. 

Correction  of  the  observations  in  Schedule  (B.)  for  the  effects  of  the  Ship's  Iron. 

Observations  in  H.M.S.  Erebus  on  her  passage  from  England  to  St.  Helena  and 
the  Cape  of  Good  Hope. 

When  commenting  in  the  Fifth  Number  of  the  Magnetic  Contributions  upon  a 
portion  of  the  magnetic  observations  of  the  two  first  years  of  Sir  James  Ross’s  Ant- 
arctic Expedition,  which  were  all  that  at  that  time  had  reached  England,  I remarked 
that  their  examination  had  led  me  to  the  opinion,  that  the  disturbances  of  the  compass 
in  the  Erebus  and  Terror  exhibited  a character  distinct  from  any  which  had  been 
previously  recognised,  either  in  theoretical  discussions  or  in  practical  applications. 
In  all  the  investigations  with  which  I was  acquainted,  in  which  the  disturbing  influ- 
ence of  a ship’s  magnetism  upon  her  compass  had  been  considered,  and  in  all  the 
remedies  which  had  been  suggested,  either  by  the  employment  of  counteracting 
forces,  or  by  corrections  to  be  applied  to  the  indications  of  a compass  where  no  such 


178 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


artificial  counteractions  were  employed,  the  magnetism  of  the  ship  had  been  regarded 
either  as  wholly  induced  by  the  magnetic  action  of  the  earth  and  as  varying  simul- 
taneously with  variations  in  the  inducing  cause,  or  as  partly  due  to  induction,  and 
partly  to  the  permanent  magnetism  of  certain  portions  of  the  ship’s  iron ; in  which 
latter  case  the  part  of  the  disturbance  occasioned  by  induction  was  considered  to  be 
variable  in  the  manner  already  described  ; and  the  part  occasioned  by  the  permanent 
magnetism  to  be  constant,  or  nearly  so. 

Upon  the  hypothesis  of  the  whole  disturbance  being  occasioned  by  induced  mag- 
netism, its  amount  in  any  particular  direction  of  the  ship’s  head  should  be  the  same, 
or  nearly  so,  in  north  and  south  dips  of  equal  amount,  but  should  have  opposite  signs; 
that  is  to  say,  the  disturbance  which  was  towards  the  west  when  the  north  end  of  the 
needle  dipped,  should  be  towards  the  east  when  the  south  end  of  the  needle  dipped, 
and  should  be  to  the  same  amount : and  if  the  further  assumption  were  correct,  that 
the  induced  magnetism  of  the  ship  changed  simultaneously  with  changes  in  the 
terrestrial  dip,  as  is  known  to  be  the  case  with  soft  iron,  the  disturbance  might  be 
altogether  (at  least  approximately)  prevented,  by  a counteracting  mass  of  soft  iron 
disposed  suitably  in  reference  to  the  place  of  the  compass  and  to  the  resultant  of  the 
ship’s  magnetic  action. 

On  the  supposition  that  the  disturbances  were  due  partly  to  the  induced  magnetism 
of  certain  portions  of  a ship’s  iron,  and  partly  to  the  permanent  magnetism  of  other 
portions,  the  calculation  of  corrections  would  become  more  complex,  as  terms  must 
be  introduced  to  represent  both  a variable  and  a constant  effect ; and  counteraction 
by  means  of  soft  iron  would  no  longer  meet  the  case.  But  a combination  of  perma- 
nent magnets  and  of  soft  iron,  each  suitably  disposed,  might,  as  was  supposed,  accom- 
plish and  preserve  an  approximate  compensation,  if  the  magnets  and  the  permanently 
magnetic  portion  of  the  ship’s  iron  maintained  their  magnetic  relations  unaltered, 
and  if  the  changes  of  the  induced  magnetism  of  the  ship  were  as  simultaneous  with 
changes  in  the  terrestrial  magnetism  as  they  were  presumed  to  be  in  soft  iron. 

The  observations  which  were  made  on  the  disturbance  of  the  compass  needle  of 
the  Erebus  and  Terror  in  the  river  Thames,  where  the  magnetic  dip  was  about  69° 
7iorth,  and  at  Hobarton,  where  the  dip  was  between  70°  and  71°  south  (the  ships  in 
both  cases  having  remained  several  months  in  the  localities  of  the  respective  dips), 
showed  that  in  the  interval  between  the  two  sets  of  observations  a change  had  taken 
place  in  the  disturbance,  corresponding  in  kind,  and  almost  precisely  in  degree,  with 
the  hypothesis  of  induced  magnetism.  The  disturbance  was  in  the  opposite  direction 
at  Hobarton  to  what  it  had  been  in  the  Thames : in  the  one  case  the  north  pole  of 
the  compass  needle  was  drawn  towards  the  fore  part  of  the  ship,  and  in  the  other 
case  the  south  pole.  The  amount  of  disturbance  in  the  one  direction  in  the  Thames, 
and  in  the  opposite  direction  at  Hobarton,  was  so  nearly  the  same — the  terrestrial 
dip  having  also  nearly  the  same  numerical  value  at  the  two  stations,  but  with  oppo- 
site signs, — as  fully  to  bear  out  the  inference,  that  in  those  two  ships  the  chief  part 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


179 


if  not  the  whole  of  the  disturbance  of  the  compass  was  occasioned  by  induced  mag- 
netism. 

Such  being  the  case,  it  might  naturally  have  been  expected  that  formulae  founded 
on  M.  Poisson’s  investigations  regarding  the  induced  magnetism  of  ships,  which  re- 
presented so  well  the  change  that  had  taken  place  between  England  and  Van  Diemen 
Island,  would  also  represent  the  disturbance  which  had  been  found  to  take  place  at 
stations  visited  by  the  ships  in  the  intermediate  passage ; and  that  the  i-esult  of  azi- 
muths observed  in  the  same  geographical  position  of  the  ship,  with  her  head  on 
different  points  of  the  compass,  would  be  brought  into  agreement  with  each  other,  at 
any  period  of  the  voyage,  by  corrections  computed  by  the  formulte  of  which  the 
variable  coeflScients  were  taken  as  varying  with  the  changes  of  the  terrestrial  dip. 

Such  however  was  by  no  means  the  case.  A table  of  corrections  was  computed  by 
the  appropriate  formulae  for  each  of  the  thirty-two  points  and  for  every  degree  of 
north  and  south  dip  ; the  values  of  the  coefficients  in  the  formulae  being  derived  from 
the  observations  in  the  Thames  and  at  Hobarton  ; and  those  which  were  variable 
being  assumed,  in  conformity  with  the  hypothesis,  to  vary  according  to  the  dip.  On 
comparing  this  table  with  the  observations  at  intermediate  times  and  stations,  it  was 
immediately  perceived  that  in  order  to  suit  the  table  to  the  observations,  it  was 
necessary  to  enter  the  table,  not  with  the  dip  at  the  time  and  place  of  the  observa- 
tion to  be  corrected,  but  with  a dip  which  had  been  passed  through  by  the  ship  several 
days  antecedently ; and  on  a more  close  and  general  examination,  this  was  found  to 
be  the  systematic  and  consistent  result  of  the  whole  comparison. 

This  result  by  no  means  contradicts  the  inference  previously  drawn,  and  based  on 
the  observations  in  the  Thames  and  at  Hobarton,  viz.  that  the  disturbances  in  the 
Erebus  and  Terror  were  chiefly  if  not  wholly  ascribable  to  induced  magnetism  ; for 
it  is  quite  conceivable  that  portions  of  a ship’s  iron,  which  are  not  permanently 
magnetic  on  the  one  hand,  nor  perfectly  soft  so  as  to  undergo  instantaneous  change 
with  changes  of  the  dip  on  the  other  hand,  may  still  derive  magnetism  by  induction 
from  the  earth,  which  may  conform  gradually  veLlhev  than  instantaneously  to  the  changes 
of  terrestrial  magnetism  corresponding  to  changes  of  the  ship’s  place ; so  that  after 
an  interval  of  greater  or  less  duration,  the  variation  of  the  magnetic  state  which  is 
characteristic  of  induced  magnetism  may  be  as  complete  in  such  portions  of  the  iron 
as  in  those  in  which  the  change  takes  place  instantaneously:  but  it  is  inconsistent 
with  the  proposed  counteraction  of  the  induced  portion  of  the  disturbance  by  means 
of  soft  iron,  unless  a degree  of  retentive  force  could  be  given  to  the  soft  iron  which 
should  be  precisely  equivalent  to  that  of  the  general  resultant  of  all  the  iron  in  a ship 
which  is  not  permanently  magnetic  ; and  which  doubtless  varies  considerably  in 
different  ships. 

Since  1843,  when  the  fifth  number  of  the  Magnetic  contributions  was  printed,  I 
have  examined  the  observations  made  in  several  ships  which  have  passed  from  one 
hemisphere  to  the  other,  and  have  found  them,  without  a single  exception,  cor- 


180 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


responding  in  character  to  those  of  the  Erebus  and  Terror.  When  a ship  is  rapidly 
changing  her  geographical  position,  or  when  she  has  just  arrived  in  port  after  making 
a recent  considerable  change  of  geographical  position,  her  magnetism  is  always  in 
arrear  (if  I may  so  express  myself)  of  the  change  which  would  be  equivalent  to  the 
change  in  the  terrestrial  dip ; but  after  she  has  remained  in  the  same  locality  a 
period,  which  may  be  supposed  to  depend  in  some  measure  on  the  rapidity  and 
amount  of  the  change  of  dip  that  she  has  passed  through,  as  well  as  on  the  parti- 
cular degree  of  retentiveness  of  her  iron,  I have  found  in  all  cases  that  have  hitherto 
come  under  my  examination,  that  the  amount  of  disturbance  in  north  and  south  dips 
of  equal  amount  becomes  ultimately  the  same,  but  with  the  opposite  sign. 

The  practical  bearing  of  these  conclusions  is  considerable.  If  the  whole  disturbance 
be  due  to  induced  magnetism, — and  if  when  changes  of  geographical  position  are  made, 
the  disturbance  is  found  to  conform  fully  to  the  laws  of  induced  magnetism  after  an 
interval  which  maybe  considered  brief  in  comparison  with  a ship’s  frequent  detention 
in  different  places,  whilst  during  that  interval  it  is  in  continual  progress  thereto, — 
permanent  magnets  are  wholly  inappropriate  for  the  purpose  of  supplying  a com- 
pensating force  in  ships  making  considerable  changes  of  geographical  position  ; and 
if  correctly  applied  in  the  one  hemisphere  they  may  even  double  the  error  they  were 
intended  to  correct  when  the  ship  is  in  the  other  hemisphere.  On  the  other  hand, 
the  compensation  by  means  of  soft  iron,  if  correctly  applied  in  the  one  hemisphere, 
may  become  after  a time  an  equally  approximate  compensation  in  the  other  hemi- 
sphere ; but  in  the  passage  from  the  one  hemisphere  to  the  other,  and  generally  when 
a ship  is  changing  rapidly  her  geographical  locality,  the  compensation  may  be  very 
imperfect ; and  errors  thus  resulting  are  the  more  likely  to  be  prejudicial  when  a 
compass  is  supposed  to  be  compensated,  because  the  habit  of  watching  for  them  is 
then  impaired.  The  counteraction  of  the  disturbance  by  the  introduction  of  a mag- 
netic force  which  should  at  all  times  counterbalance  that  of  the  ship,  would  seem 
therefore  to  be  a more  complicated  problem  than  it  has  been  supposed  to  be : for 
neither  permanent  magnets,  nor  iron  which  changes  simultaneously,  can  afford 
separately  or  conjointly  suitable  compensation  for  disturbances  which  are  in  part  at 
least  a function  of  time. 

Nor  are  these  conclusions  without  a practical  bearing  on  the  applicabilities  of  the 
formulae  which  have  been  derived  from  theoretical  investigations,  for  the  purpose  of 
supplying  corrections  for  the  disturbing  influence  of  a ship’s  iron  on  her  compass,  and 
on  other  magnetical  instruments  employed  on  board  ship:  for  it  becomes  necessary 
to  take  into  account,  in  addition  to  the  two  qualities  of  iron  previously  recognised 
and  for  which  terms  were  provided,  a third  portion  which  is  of  an  intermediate 
quality  between  the  other  two,  and  of  which  the  magnetism  is  neither  permanent  on 
the  one  hand,  nor  are  its  changes  simultaneous  with  or  immediately  consequent  on 
changes  of  the  terrestrial  dip.  Even  in  the  most  simple  case  of  the  disturbances 
being  occasioned  chiefly  or  wholly  by  induced  magnetism,  the  data  which  are 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


181 


furnished  by  swinging  a ship  in  harbour,  even  if  repeated  in  more  than  one  locality, 
must  be  insufficient  to  furnish  corrections  for  the  observations  which  may  be  made 
at  sea  in  passages  from  port  to  port,  if  unaccompanied  by  experimental  data  furnished 
from  time  to  time  during  the  passages  themselves. 

Seeing  therefore  the  importance  of  the  conclusions  to  which  I have  been  led,  I have 
thought  it  desirable  to  collect  together  in  one  point  of  view  on  the  present  occasion 
all  the  observations  which  were  made  in  the  Erebus  for  the  purpose  of  examining  the 
disturbance  of  the  compass,  during  the  three  years  in  which  she  was  employed  in 
the  Antarctic  Expedition,  and  to  enter  on  a somewhat  detailed  discussion  of  them. 


Table  I. — Disturbance  of  the  Compass  in  H.M.S.  Erebus. 

+ Implies  a disturbance  of  the  North  end  of  the  needle  towards  the  West ; 

— towards  the  East. 


Direction 

of 

ship’s  head. 

Gillingham 
S eptember 
1839. 

Port  Praya, 
November 
1839. 

St.  Helena, 
February 
1840. 

Cape  of 
Good  Hope, 
April 
1840. 

Kerguelen 

Island, 

July 

1840. 

Hobarton, 

October 

1840. 

Hobarton, 

June 

1841. 

Falkland 

Islands, 

August 

1842. 

Cape  of 
Good  Hope, 
April 
1843. 

Direction 

of 

ship’s  head. 

O 

/ 

O 

/ 

O 

16 

O 

O 

/ 

O 

/ 

O 

O 

/ 

N.  by  w. 

+ 1 

12 

+ 0 

27 

-0 

02 

+0 

-0 

27 

-0 

35 

— 1 

28 

-0 

04 

-0 

37 

N.  by  w. 

N.N.W. 

+ 2 

01 

-fo 

20 

-0 

27 

+ 0 

10 

— 1 

08 

-0 

29 

-2 

15 

-0 

34 

— 1 

04 

N.N.W. 

N.w.  by  N. 

+ 2 

10 

+ 0 

52 

-0 

34 

+ 0 

02 

-2 

07 

— 1 

43 

-2 

48 

-0 

51 

— 1 

15 

N.W.  by  N. 

N.W. 

-1-3 

03 

+ 1 

15 

-0 

40 

-0 

03 

— 2 

02 

— 1 

59 

-3 

09 

— 1 

02 

— 1 

42 

N.w. 

N.w.  by  w. 

+ 3 

28 

+ 1 

25 

— 1 

03 

-0 

15 

-2 

27 

-2 

47 

-3 

27 

— 1 

01 

-2 

01 

N.W  by  w. 

W.N.W. 

-f3 

51 

-hi 

05 

-0 

25 

-0 

33 

— 3 

12 

— 3 

07 

— 4 

04 

— 1 

49 

-2 

35 

W.N.W. 

w.  by  N. 

+ 4 

09 

+ 1 

15 

-0 

29 

-0 

51 

-3 

36 

-3 

37 

— 4 

47 

-2 

10 

-2 

54 

w.  by  N. 

w. 

-1-4 

19 

+1 

33 

-0 

32 

— 1 

09 

-3 

41 

-4 

03 

-5 

13 

-2 

16 

— 3 

09 

w. 

w.  by  s.' 

-1-4 

40 

+ 1 

49 

— 0 

12 

— 1 

14 

-3 

56 

— 4 

02 

— 5 

11 

-2 

21 

-3 

17 

w.  by  s. 

w.s.w. 

-b4 

03 

-f  1 

24 

-1-0 

09 

— 1 

05 

-4 

06 

-4 

16 

— 4 

55 

— 2 

21 

-3 

09 

w.s.w. 

s.w.  by  w. 

+ 3 

24 

+ 1 

34 

+ 0 

08 

—1 

06 

-3 

47 

— 4 

27 

-4 

33 

-2 

14 

-2 

52 

s.w.  by  w. 

s.w. 

+ 2 

45 

+ 0 

26 

+ 0 

04 

-0 

52 

-3 

23 

-3 

55 

-3 

54 

— 1 

58 

— 2 

27 

s.w. 

s.w.  by  s. 

+ 2 

08 

-1-0 

09 

+ 0 

14 

-0 

40 

— 2 

34 

-3 

24 

-3 

13 

-1 

43 

— 1 

52 

s.w.  by  s. 

s.s.w. 

+ 1 

34 

-0 

02 

-0 

01 

-0 

02 

— 1 

53 

— 2 

18 

— 2 

30 

— 1 

17 

— 1 

12 

s.s.w. 

s.  by  w. 

+ 0 

52 

-hO 

10 

— 0 

09 

+ 0 

16 

-0 

45 

— 1 

27 

-0 

34 

-0 

39 

-0 

07 

s.  by  w. 

s. 

+ 0 

28 

-0 

39 

-0 

29 

+ 0 

39 

+ 0 

22 

-0 

38 

-hO 

29 

0 

00 

4-0 

33 

s. 

s.  by  E. 

— 0 

19 

-0 

32 

-0 

24 

+ 1 

14 

+ 1 

10 

+ 0 

21 

+ 2 

18 

+ 0 

44 

+ 1 

07 

s.  by  E. 

S.S.E. 

-0 

48 

-0 

42 

-0 

30 

-hi 

26 

-h2 

05 

+ 0 

39 

+ 2 

52 

+ 1 

13 

+ 1 

45 

S.S.E. 

s.E.  by  s. 

— 1 

23 

-0 

25 

-0 

25 

+1 

41 

+ 2 

50 

+ 1 

24 

-h3 

37 

+ 1 

41 

+ 2 

08 

S.E.  by  s. 

S.E. 

—1 

53 

— 1 

09 

-0 

21 

+ 2 

53 

+ 3 

21 

+ 1 

56 

4-4 

20 

+ 1 

55 

+ 2 

31 

s.E. 

s.E.  by  E. 

-2 

21 

— 1 

25 

— 0 

21 

+ 2 

01 

+ 3 

51 

+1 

46 

-h4 

46 

+ ^ 

07 

+ 2 

51 

S.E.  by  E. 

E.S.E. 

~2 

50 

— 1 

18 

-0 

06 

-hi 

43 

-h4 

12 

-h3 

29 

-h5 

31 

+ 2 

19 

+ 3 

15 

E.S.E. 

E.  by  s. 

— 3 

17 

-1 

44 

+ 0 

13 

+ 1 

34 

+ 3 

53 

-h3 

23 

-h5 

06 

+ 2 

16 

+ 3 

10 

E.  by  s. 

E. 

-3 

42 

— 1 

56 

+ 0 

32 

+ 1 

15 

-h3 

48 

+ 3 

50 

-h4 

53 

4-2 

07 

+ 2 

46 

E. 

E.  by  N. 

— 4 

53 

—2 

40 

+ 0 

55 

-hi 

02 

+ 3 

31 

+ 4 

06 

-h4 

32 

+ 1 

54 

+ 2 

30 

E.  bv  N. 

E.N.E. 

— 3 

46 

-2 

47 

+ 0 

57 

-hi 

51 

+ 3 

02 

+ 3 

41 

-h3 

52 

4-1 

44 

+ 2 

15 

E.N.E. 

N.E.  by  E. 

— 3 

18 

— 2 

30 

+ 0 

48 

-hO 

31 

+ 2 

13 

-h3 

33 

-h3 

31 

+ 1 

16 

+ 1 

59 

N.E.  by  E. 

N.E. 

— 2 

59 

— 2 

10 

-hi 

11 

+ 0 

22 

+ 2 

10 

-h3 

23 

+ 2 

54 

+ 0 

51 

4-1 

33 

N.E. 

N.E.  by  N. 

-2 

16 

— 2 

12 

-hO 

52 

-hO 

11 

+ 1 

32 

+ 3 

01 

-h2 

25 

+ 0 

41 

+ 1 

15 

N.E.  by  N. 

N.N.E. 

— 1 

39 

-1 

53 

-f  0 

28 

+ 0 

01 

+ 1 

01 

+ 2 

37 

-hi 

15 

+ 0 

41 

+ 0 

43 

N.N.E. 

N.  by  E. 

— 0 

49 

— 1 

17 

+ 0 

17 

+0 

24 

+ 0 

23 

h2 

17 

+ 0 

23 

+ 0 

28 

+ 0 

15 

N.  by  E. 

N. 

+ 0 

06 

-0 

56 

+ 0 

05 

+ 0 

24 

-0 

08 

-hi 

12 

+ 0 

41 

+ 0 

13 

-0 

20 

N. 

From  the  observations  in  September  1839,  at  Gillingham  in  the  River  Thames 
(where  the  ship  had  been  stationary  for  many  months),  a table  was  formed  by  the 
well-known  formulse  derived  from  Poisson’s  fundamental  equations  applicable  to  in- 
MDCCCXLIX.  2 B 


182 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


duced  magnetism, giving  the  corrections  which,  on  that  hypothesis,  and  on  the  further 
supposition  that  the  changes  in  the  induced  magnetism  of  the  ship  were  simultaneous 
with  those  of  terrestrial  magnetism,  should  have  corresponded  with  the  disturbance 
on  each  of  the  thirty-two  points  of  the  compass  under  every  degree  of  the  terrestrial 
dip.  On  examining,  by  means  of  this  table,  the  number  of  degrees  of  dip  by  which 
it  was  necessary  to  go  back  from  the  dip  at  the  place  of  observation,  in  order  to 
obtain  from  the  table  corrections  corresponding  to  the  disturbances  at  the  stations 
where  the  ship  was  subsequently  swung,  I find  that  at  Port  Praya,  where  the  dip  was 
H-45°  32',  and  after  a passage  of  thirty-six  days  from  the  British  Channel,  where  the 
dip  was  about  +69°,  that  the  ship’s  magnetism,  instead  of  corresponding  to  a dip  of 
+ 45°  32',  did  in  fact  correspond  to  a dip  of  about  +51°^ ; the  arrear  being  about  6°. 

At  St.  Helena,  where  the  dip  was  about  —20°,  and  where  the  ship  had  arrived  after 
a passage  of  about  seventy-nine  days  from  Port  Praya,  during  which  she  had  passed 
from  north  into  south  dip,  the  arrear  was  between  thirty  and  forty  degrees — the 
tabular  corrections  for  20°  north  dip  corresponding  more  nearly  with  the  differences 
of  the  azimuths  observed  at  St.  Helena  with  the  ship’s  head  on  different  points,  than 
did  the  tabular  corrections  for  20°  south  dip  ; so  that  the  effect  of  the  employment  of 
the  latter  would  manifestly  have  been  to  have  increased  the  evil  which  they  were  in- 
tended to  correct. 

At  the  Cape  of  Good  Hope,  where  the  dip  was  —53°,  and  after  an  interval  of  thirty- 
eight  days  from  her  departure  from  St.  Helena,  the  arrear  appears  to  have  been  about 
twelve  degrees. 

At  Kerguelen  Island,  where  the  ship  arrived  after  a passage  of  forty  days  from 
the  Cape,  but  where  she  remained  in  harbour  about  fifty  days  before  the  disturbance 
experiments  were  made,  the  tabular  corrections  had  overtaken  the  terrestrial  dip, 
although  the  latter  had  increased  from  — 53°  at  the  Cape  to  —70°  at  Kerguelen  Island ; 
above  one  hundred  days  had  elapsed  between  the  experiments  in  — 53°  and  those 
in  —70°  of  dip,  of  which  less  than  half  the  number  were  occupied  in  making  the 
passage  from  the  dip  of  —53°  to  that  of  —70°,  and  the  rest  were  passed  at  the 
anchorage  in  —70°.  From  Kerguelen  Island  the  Erebus  proceeded  to  Hobarton, 
where  the  dip  was  the  same,  within  a degree,  as  at  Kerguelen  Island,  being  —70°  40', 
and  where,  as  I have  already  stated,  the  disturbances  were  found  to  be,  both  in  kind 
and  amount,  very  nearly  such  as  might  have  been  computed  beforehand  from  the 
observations  in  the  Thames,  by  the  formulae  which  apply  to  induced  magnetism  sus- 
ceptible of  instantaneous  change,  the  tabular  corrections  compensating  the  disturb- 
ances within  the  limits  of  the  usual  errors  of  observation. 

From  Hobarton  the  Erebus  proceeded,  in  November  1840,  to  the  high  geographical 
latitudes  of  the  southern  hemisphere,  and  remained  for  some  months  in  south  dips 
much  exceeding  that  at  Hobarton,  to  which  station  she  returned  in  April  1841.  On 
the  29th  of  June  1841,  being  about  eleven  weeks  after  her  arrival  in  harbour,  observa- 
tions were  made  on  the  disturbances  of  the  compass  on  each  of  the  thirty-two  points. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  iiTLANTIC. 


183 


The  aiTear  was  now  found  to  be  on  the  side  of  the  hig-her  dips,  though  probably  to  a 
much  less  amount  than  might  have  been  the  case  had  the  observations  been  made  at 
an  earlier  period  after  her  return ; the  tabular  corrections  which  most  nearly  corre- 
spond to  the  observed  disturbances  are  those  of  the  dip  —71°  28'  instead  of  — 70°  40'. 

The  expedition  left  Hobarton  a second  time  in  July  1841,  passing  the  following 
(Antarctic)  summer  again  in  the  regions  of  high  southern  dip,  and  returning  to  the 
Falkland  Islands  in  April  1842,  where  the  dip  was  between  —52°  and  —53°;  the 
observations  on  the  disturbances  of  the  eornpass  were  made  in  August,  being  about 
four  months  after  the  ship  arrived ; an  arrear  however  still  remained  on  the  side  of 
the  high  dips  in  whieh  several  months  had  been  passed  previously  to  her  arrival ; the 
tabular  corrections  corresponding  to  the  disturbances  are  those  belonging  to  a dip  of 
between  — 56°  and  —57°,  instead  of  between  —52°  and  —53°. 

From  the  Falkland  Islands  the  Erebus  sailed  once  more  for  the  high  latitudes  in 
December  1842,  returning,  on  this  occasion,  to  the  Cape  of  Good  Hope  in  April  1843. 
She  had  now  been  in  localities  of  higher  southern  dip  than  that  of  the  Cape  during 
nearly  the  whole  of  the  three  years  whieh  had  elapsed  since  her  former  visit  to  the 
Cape,  and  she  had  passed  the  three  months  immediately  antecedent  to  her  second 
arrival,  in  dips  varying  from  —60°  to  —65°,  that  of  the  Cape  at  the  same  period  being 
— 53°  30'.  The  disturbances  of  the  compass  were  examined  on  the  20th  of  April, 
being  a very  few  days  after  her  arrival  at  the  Cape,  and  I find  that  the  tabular  cor- 
rections corresponding  to  them  are  those  belonging  to  a dip  of  about  —63°  30'.  The 
arrear  on  this  occasion  was  therefore  about  10°  on  the  side  of  the  higher  dips,  it 
having  been  about  12°  on  the  side  of  the  lower  dips  when  the  ship  arrived,  in  1840, 
at  the  same  station  from  localities  of  lower  dip. 

The  experiments  at  the  Cape  in  April  1843  were  the  last,  I understand,  that  were 
made  in  the  Erebus  during  the  progress  of  the  voyage,  for  the  purpose  of  examining 
the  influence  of  the  ship’s  iron  on  her  compass  by  tlie  usual  process  of  swinging  the 
ship;  and  by  an  unfortunate  misunderstanding,  the  repetition  of  the  experiments  on 
the  return  of  the  vessel  to  the  Thames,  which  had  been  ordered  by  the  Admiralty, 
and  was  fully  designed  to  have  taken  place  by  Sir  James  Ross,  was  also  omitted. 
It  appears  therefore  that  in  every  instance  in  which  the  proper  experiments  were 
made,  the  disturbances  were  found  to  be  consistent  with  the  hypothesis  of  an  induced 
magnetism  conforming  gradually  to  the  changes  in  the  terrestrial  magnetic  pheno- 
mena occasioned  by  the  changes  in  the  ship’s  geographical  position,  but  not  changing 
simultaneously  with  those  changes. 

But  whether  the  hypothesis  of  a gradual  conformity  of  a part  of  the  ship’s  iron, 
instead  of  an  instantaneous  conformity  of  the  whole,  to  changes  of  the  terrestrial 
dip,  be  or  be  not  the  true  explanation  of  the  facts  which  have  been  thus  pointed  out, 
the  facts  themselves  are  highly  deserving  of  consideration  by  those  to  whom  the  cor- 
rection of  compass  errors  is  of  consequence  ; the  anomalies  which  present  themselves 
to  any  previously  entertained  systematic  view  are  of  too  large  amount,  as  well  as  too 
consistent  on  the  different  points,  both  in  the  observations  at  sea  and  in  harbour,  to 

2 B 2 


184 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


be  ascribed  either  to  errors  of  observation  or  to  accidents ; and  the  prominency  which 
lias  been  given  to  them  on  this  occasion  will  not  be  misplaced,  if  it  should  serve  to 
impress  upon  those  who  have  the  power  of  carrying  out  practical  suggestions,  the 
importance  of  giving  a sufficient  trial  to  the  method  proposed  by  Mr.  Archibald 
Smith  in  the  eighth  number  of  the  Magnetic  Contributions,  whereby  the  variable 
term  in  the  correction  formula  may  be  at  all  times  determined  experimentally  at  sea, 
by  deflections  of  the  compass  needle  obtained  with  the  ship’s  head  on  two  opposite 
points  of  the  compass.  The  observations  needed  are  extremely  simple,  require  no 
unusual  circumstances  of  weather  and  no  reference  to  celestial  objects,  and  need 
occupy  but  a very  few  minutes. 

Mr.  Smith  has  shown  that  the  variable  term  may  also  be  determined  at  sea  by  ob- 
servations of  azimuths  with  the  ship’s  head  placed  on  the  points  of  greatest  disturbance; 
but  the  deflection  method  promises  to  be  even  more  simple  than  that  by  azimuths. 
By  the  addition  of  a brass  bar  attached  at  right  angles  to  the  prism  and  sight  vane 
of  the  azimuth  ring  of  the  standard  compass,  deflecting  magnets  may  be  temporarily 
fixed  at  a convenient  distance  from  the  compass  needle,  and  the  deflections  measured 
with  the  ship’s  head  on  two  opposite  points ; as  was  first  practised  by  Captain  (then 
Lieut.)  Henry  Clerk,  R.A.,  F.R.S.,  in  his  Antarctic  voyage*. 

If  this  rnetliod  of  determining  the  variable  coefficient  in  the  correction  formulae  be 
found  to  answer  its  purpose  on  a further  and  sufficient  trial,  the  correction  of  the  dis- 
turbances occasioned  by  the  ship’s  iron  might  be  still  further  simplified  by  the  formation 
of  tables  of  each  term  for  every  probable  value  of  the  coefficients,  when  the  only  calcu- 
lation remaining  to  be  made  would  be  the  addition  of  the  quantities  to  be  taken  out 
from  the  tables.  In  wooden  ships,  two  terms,  and  consequently  a single  addition, 
would  probably,  in  most  cases,  be  sufficient  for  the  whole  amount  of  the  correction -f'. 

With  reference  to  the  corrections  which  we  have  now  occasion  to  employ  for  the 
declinations  observed  in  the  Erebus  in  her  passage  from  England  to  the  Cape  of  Good 
Hope,  we  have  the  following  values  of  the  constant  coefficients  A,  D and  E in  the 
formula  (6.):|:,  derived  from  the  observations  on  the  thirty-two  points  of  the  com- 
pass, at  the  several  stations  at  which  these  observations  were  repeated,  by  the  equa- 
tions (16.),  (19.)  and  (20.)  §. 


A. 

D. 

E. 

Gillingham 

-f  16 

- 3 

Port  Praya 

. . -23 

-1-24 

— 8 

St.  Helena 

+27' 

+ 3 

Cape  of  Good  Hope,  1840  . . . 

. . -1-23 

-1-23 

+ 15 

Mean  . . . 

. . -H  5 

-1-22 

+ 2 

* Philosophical  Transactions,  1846,  p.  347. 

t Whilst  these  pages  were  in  the  press,  tables  such  as  are  here  referred  to  have  been  drawn  up  and  printed 
under  the  direction  of  the  Admiralty  in  a tract  entitled  “ Directions  for  ascertaining  at  any  time,  whether  at 
sea  or  in  harbour,  the  changing  part  of  the  Deviation  in  the  Compass  occasioned  by  the  Ship’s  Iron.” 

I Philosophical  Transactions,  1846,  p.  348.  § Ibid.  pp.  350  and  351. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


185 


From  the  small  amount  of  the  mean  value  of  A,  we  may  infer  that  the  iron  which 
affected  the  compass  was  distributed  systematically,  or  nearly  so,  on  either  side  of  the 
midship  line ; the  variations  in  the  values  at  different  stations  are  greater  than  could 
be  wished,  but  they  have  no  regular  appearance,  and  may  probably  be  due  to  acci- 
dental circumstances,  which  in  such  experiments  cannot  possibly  be  wholly  guarded 
against.  Considering  the  small  mean  value  of  the  coefficient,  and  the  extent  of  its 
variations  on  the  different  occasions,  we  may  dispense  altogether  with  its  further 
consideration.  A similar  remark  will  apply  to  E;  since  if  its  mean  value  were 
employed,  the  maxitnum  effect  on  the  correction  would  in  no  instance  exceed  two 
minutes.  But  it  is  otherwise  with  regard  to  D,  which  has  a very  sensible  value  in 
respect  to  the  whole  amount  of  the  correction,  especially  in  low  latitudes ; and  the 
deductions  in  regard  to  it  are  tolerably  consistent  at  the  different  stations ; I have 
taken  its  mean  value  at  -\-22'. 

For  the  variable  coefficients  B and  C,  we  have  not  the  advantage  of  possessing  the 
experimental  determinations  at  sea,  which  have  been  pointed  out  as  possible  to  be 
made  on  future  occasions  with  the  deflecting  apparatus  ; and  we  must  therefore  obtain 
these  also  from  the  observations  in  harbour  in  the  best  manner  that  circumstances 
will  admit. 

Commencing  with  B as  the  more  important,  we  have  the  following  values  at  the 
four  stations  for  the  passages  between  which  the  corrections  are  required.  (The 


values  are  expressed  by  the  sines  of  the  respective  arcs) : — 

Dip.  B. 

Gillingham,  September  20,  1839  -1-69  05  -l-‘0675 

Port  Praya,  November  18,  1839 -4-45  32  -l-'0324 

St.  Helena,  February  8,  1840  —20  06  -l-'0073 

Cape  of  Good  Hope,  April  4,  1840  —53  02  —•0219 


If  from  these  values  of  B we  seek  intermediate  values  corresponding  to  interme- 
diate dips  or  times,  we  are  obliged,  for  the  reasons  already  stated,  to  have  recourse  to 
some  more  or  less  arbitrary  supposition.  It  has  been  already  shown  that  the  inter- 
mediate values  cannot  be  computed  directly  from  the  observations  of  the  dip  ; and  if 
the  explanation  which  has  been  proposed  be  correct,  it  may  not  be  unreasonable  to 
regard  the  variation  of  this  coefficient  as  a function  of  the  time  elapsed  rather  than  of 
the  change  of  dip.  In  two  of  the  three  passages  at  least,  viz.  from  the  British  Channel 
to  Port  Praya  and  from  St.  Helena  to  the  Cape,  this  might  be  the  more  safely  assumed, 
because  the  ship’s  progress  with  respect  to  the  terrestrial  dip  was  uninterrupted,  in 
the  first  case  to  diminishing  north  dips,  and  in  the  second  to  diminishing  south  dips. 
In  the  first  case  we  have  a change  in  B of  *0351  in  fifty-nine  days,  or  *00059  per  diem, 
and  in  the  second  of  '0292  in  fifty-six  days,  or  *00052  per  diem.  In  the  voyage  from 
Port  Praya  to  St.  Helena  the  progress  in  respect  to  the  change  of  dip  was  uninterrupted 
from  the  period  of  departure  from  Port  Praya  on  the  21st  of  November  1839  to  the 
2nd  of  January  1840,  the  dip  having  diminished  in  that  interval  from  -1-45°  32'  at  Port 
Praya  to  between  —29°  and  —30°.  But  from  the  2nd  of  January  the  ship,  in  beating 


186 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


up  to  St.  Helena,  gradually  though  interruptedly,  diminished  the  southerly  dip,  which 
at  St.  Helena  is  about  —20°.  The  2nd  of  January  may  therefore  be  regarded  as 
dividing  this  part  of  the  voyage  into  two  portions  in  respect  to  the  changes  of  B.  As 
the  daily  rates  of  change  deduced  above  for  the  passages  from  the  Thames  to  Port 
Praya  and  from  St.  Helena  to  the  Cape  ('00059  and  ’00052)  differ  so  little  from  each 
other,  we  may  not  unreasonably  take  their  mean  as  applicable  to  the  first  division  of 
this  part  of  the  voyage,  or  for  that  division  in  which  the  change  of  dip  was  continuous 
and  uninterrupted.  This  gives  as  the  value  of  B on  the  2nd  of  January  +*0074. 
Now  at  St.  Helena  we  find  it  by  experiment  +‘0073  ; on  this  assumption  consequently 
the  magnetism  of  the  ship  would  have  remained  nearly  stationary  from  the  2nd  of 
January  to  the  arrival  at  St.  Helena,  which  is  by  no  means  an  improbable  supposition. 

We  may  derive  intermediate  values  of  C in  a similar  manner*.  This  coefficient  is 
however  of  very  minor  importance. 

It  will  of  course  be  understood  that  this  mode  of  deriving  these  coefficients  is  one 
which  would  only  be  adopted  in  the  absence  of  more  satisfactory  data ; and  fortunately 
in  the  part  of  the  globe  for  which  the  corrections  are  required  the  values  of  B and  C 
are  less  significant  than  in  the  higher  latitudes.  The  observations  themselves,  how- 
ever, furnish  a test  by  which  the  appropriateness  of  this  or  of  any  other  hypothesis 
proposed  for  their  correction  may  be  judged,  viz.  by  the  measure  of  agreement  into 
which  the  corrections  bring  observations  made  on  the  same  day  or  near  the  same 
spot  with  the  ship’s  head  on  different  points.  Without  entering  into  details,  it  may 
be  stated,  generally,  that  the  corrections  computed  by  the  formula  (6.)  with  the  value 
of  the  coefficients  as  above  stated  appear  to  bear  this  test  very  satisfactorily ; the 
observations  thus  corrected  becoming  much  more  accordant  with  each  other  than 
either  when  uncorrected,  or  than  when  corrected  by  the  same  formula  with  its 
variable  coefficients  made  to  vary  in  accordance  with  the  dip. 

Determinations  in  H.M.S.  Erehus,  in  1842  and  1843,  between  Cape  Horn  and.  the 

Cape  of  Good  Hope. 

For  the  corrections  of  the  declinations  observed  in  the  Erebus  in  1842-43  between 
Cape  Horn  and  the  Cape  of  Good  Hope,  we  have  seen,  p.  184,  that  the  value  of  the 
constant  coefficient  D as  derived  from  the  experiments  in  the  River  Thames  and  Port 
Praya  in  1839,  and  at  St.  Helena  and  the  Cape  of  Good  Hope  in  1840  was  +22';  for 
the  experiments  at  the  Falkland  Islands  in  August  1842,  D=+23',  and  from  those 
at  the  Cape  in  1843,  +24';  I have  made  no  alteration  therefore  in  the  general  table 
of  corrections  which  was  computed,  as  already  noticed,  with  +22'. 

For  the  variable  coefficients  B and  C we  possess  no  other  data,  for  the  period 
now  under  consideration,  than  the  values  derivable  from  the  experiments  in  the  Falk- 

* Values  of  C derived  from  the  harbour  observations  : — 


Gillingham  — '0036 

Port  Praya — '0046 

St.  Helena -'0033 

Cape  of  Good  Hope — '0044 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


187 


land  Islands  in  Aug-ust  1842,  and  at  the  Cape  of  Good  Hope  in  April  1843;  from 
these  we  obtain, — 

At  the  Falkland  Islands  ....  B = — -0377;  C=+-0009. 

At  the  Cape  of  Good  Hope  . . . B = — ‘0517;  C=— *0040. 

It  has  been  already  noticed  that  the  term  x/B^-j-C^,  derived  from  these  values, 
was  on  both  occasions  numerically  greater  than  would  have  been  assigned  from  the 
dips  at  the  respective  stations,  and  the  values  of  the  same  coefficients  at  other  stations 
where  the  ship  had  remained  sufficiently  long  for  the  full  development  of  the  changes 
in  its  induced  magnetism  corresponding  to  changes  of  geographical  position.  The 
experiments  at  the  Falkland  Islands  and  at  the  Cape  of  Good  Hope,  afford  however 
the  best  indication  which  we  possess  of  the  magnetic  state  of  the  ship  in  the  interval 
comprised  between  their  respective  dates,  and  must  betaken  as  the  foundation  of  the 
corrections  during  that  interval.  In  September  1842  the  Erebus  quitted  Port  Louis 
in  the  Falkland  Islands  for  Cape  Florn,  and  after  remaining  some  weeks  at  St.  Mar 
tin’s  Cove,  where  the  dip  was  between  —58"^  and  —59°,  returned  in  November  to  the 
Falkland  Islands;  from  whence  she  sailed  immediately  afterwards  to  resume  the 
magnetic  survey  of  the  higher  latitudes,  arriving  at  the  Cape  of  Good  Hope  in  April 
1843.  In  the  whole  interval  between  August  1842  and  April  1843,  the  ship  was  at 
no  time  in  a lower  dip  than  that  at  the  Falkland  Islands,  and  we  may  presume  there- 
fore, with  much  probability,  that  the  ^B^-l-C^  was  in  no  part  of  the  interval  less 
than  its  value  at  Port  Louis.  We  have  thus  a minimum  value  for  this  term.  During 
January  1843  the  dips  observed  in  the  Erebus  ranged,  in  different  localities,  from 
— 60°  to  —63°.  In  February  from  —58°  to  —62°;  in  the  first  week  of  March  a 
favourable  opportunity  presenting  itself  for  pressing  to  the  southward,  the  dip  in- 
creased to  between  —65°  and  —66°;  but  from  the  8th  of  March  it  progressively  di- 
minished until  the  arrival  at  the  Cape  on  the  6th  of  April.  The  experiments  made 
at  the  Cape  on  the  20th  of  that  month  gave  a value  of  \/B^-}-C^,  corresponding  to 
—63°,  or  thereabouts.  It  is  not  probable  from  this  review  that  ^/B'^+C^  was  at  any 
time  much  higher  than  it  was  found  at  the  Cape ; it  may  possibly  have  been  a little 
higher  for  some  days  in  March,  but  I have  thought  it  safer  to  keep  within  the  limits 
which  were  actually  observed  than  to  assume  a conjectural  maximum  ; and  in  cor- 
recting the  declinations  of  this  period  I have  accordingly  taken  the  value  of  ^B^-j-C^ 
observed  at  Port  Louis  as  applicable  until  the  Erebus  sailed  for  the  higher  latitudes 
in  December  1842,  and  have  then  increased  it  uniformly  and  progressively  with  the 
time  until  the  first  week  in  January  1843,  when  the  dip  was  —63°,  corresponding  to 
the  highest  observed  value  of  -^/B^-j-C^;  and  I have  used  that  value  thenceforward 
until  the  arrival  at  the  Cape,  where  it  accorded  with  the  experiments. 

By  the  following  memorandum  with  which  I have  been  furnished  by  Mr.  Tucker, 
Master  of  the  Erebus,  it  appears  that  the  standard  compass  of  that  ship  had  an  index 
error  of  considerable  amount  during  this  portion  of  the  voyage.  I have  not  been 
able  to  learn  anything  satisfactory  in  regard  to  the  cause  of  this  error,  which  did  not 
exist  when  the  compass  was  tried  by  Captain  Johnson,  R.N.,  before  the  expedition 


188 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


quitted  England  ; nor  could  it  have  existed  when  the  ship  was  swung  in  the  River 
Thames,  at  Port  Praya,  or  at  the  Cape  of  Good  Hope  in  1 840,  or  it  would  have  ap- 
peared to  its  full  amount  in  the  value  derived  for  the  coefficient  A.  The  evidence, 
however,  afforded  by  the  consistent  results  of  the  several  trials  that  were  made  both 
at  the  Falkland  Islands  and  at  St.  Martin’s  Cove  in  1842,  and  both  on  shore  and  on 
board,  leaves  no  doubt  of  the  existence  of  index  error  at  that  period. 

I cannot  find  that  any  trial  was  made  of  the  index  error  of  this  compass  on  the 
arrival  at  the  Cape  in  April  1843  ; but  in  the  neighbourhood  of  the  Cape  the  Erebus 
crossed  the  track  of  the  Pagoda,  the  observations  of  which  ship  are  published  in  the 
Philosophical  Transactions  for  1846,  Part  III.,  and  the  declinations  observed  in  the 
two  ships  agree  when  the  index  error  observed  at  the  Falkland  Islands  is  employed 
for  the  compass  of  the  Erebus,  but  would  disagree  to  an  amount  of  nearly  two  de- 
grees if  that  correction  were  not  employed. 

Mr.  Tucker’s  memorandum  is  as  follows  : — 

“The  compass  error  of  the  standard  compass  of  the  Erebus  was  ascertained  at 
Port  Louis  in  the  Falkland  Islands,  on  the  13th  of  August  1842,  in  the  following 
manner.  The  compass  with  its  card  CCH  was  taken  on  shore,  and  its  tripod  was 
fixed  over  the  spot  on  which  the  transit  had  been  established  ; the  bearings  of  the  N. 
and  S.  meridian  marks  were  then  taken  with  the  compass  as  follows  : 

North  mark N.  15°  36''8W. 

South  mark S.  15°  40'  E. 

The  true  declination  was  17°  33'  E.  in  the  month  of  August  by  the  declinometers  of 
the  observatory;  the  error  of  the  standard  compass  was  therefore  17°  33'  —15°  38''5 
= 1°  54''5,  or  the  north  end  pointed  1°  54''5  to  the  west  of  the  true  magnetic  north. 
The  compass  was  taken  again  on  shore  at  the  same  place  in  September  and  December, 
and  at  St.  Martin’s  Cove  in  November,  and  the  compass  error  was  tried  in  the  same 
way,  and  was  found  on  all  those  occasions  to  Le  within  a few  minutes  the  same  as 
that  above  stated.  Also  when  the  ship  was  swung  at  Port  Louis  on  the  19th  of 
August  1842,  the  sum  of  the  declinations  observed  with  the  standard  compass  in  its 
usual  place  on  board,  on  the  thirty-two  points,  divided  by  thirty-two,  made  a mean 
declination  of  —15°  39'’3  ; the  true  magnetic  declination  in  the  same  month  by  the 
declinometer  was  —17°  33',  whence  the  compass  error  equals  1°  53''7  to  the  westward 
of  north.” 

In  conformity  with  this  memorandum  I have  employed  —1°  54'  as  an  index  cor- 
rection from  August  1842  to  April  1843. 

Determinations  in  H.M.S.  Terror,  in  1842  and  1843,  between  Cape  Horn  and  the 

Cape  of  Good  Hope. 

The  disturbance  of  the  compass  of  the  Terror  was  examined  at  the  Falkland  Islands 
on  the  17th  of  August  1842,  and  at  the  Cape  of  Good  Hope  on  the  20th  of  April 
1843,  by  azimuths  observed  with  the  ship’s  head  successively  on  the  thirty-two 
points.  Assuming  the  mean  of  the  azimuths  on  the  thirty-two  points  to  give  the  true 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC.  189 

declination  (i.  e.  the  coefficient  A=0),  the  disturbance  on  the  several  points  are  as 
follows,  viz. — 


Table  II. — Disturbance  of  the  Compass  in  H.M.S.  Terror. 


Disturbances  towards  the  west. 

Disturbances  towards  the  west. 

Ship’s  head. 

Falkland 

Islands, 

Aug.  17,  1842. 

Cape  of 
Good  Hope, 
April  20, 1843. 

Ship’s  head. 

Falkland 

Islands, 

Aug.  17,  1842. 

Cape  of 

Good  Hope, 
April  20, 1843. 

N. 

+ 0 18 

-6  58 

s. 

-6  16 

+ 6 44 

N.  by  w. 

-0  02 

— 1 3 

s.  by  E. 

-0  08 

+ 1 56 

N.N.W. 

-0  17 

-1  6 

S.S.E. 

0 00 

+ 3 1 

K.w.  by  N. 

-0  48 

— 1 22 

s.E.  by  s. 

+ 0 47 

+ 3 2 

N.W. 

-1  19 

-2  20 

S.E. 

+ 1 .35 

+ 3 5 

N.w.  by  \T. 

-1  49 

— 2 12 

S.E.  by  E. 

+ 2 17 

+ 3 3 

W.N.W. 

-1  47 

-3  14 

E.S.E. 

+ 3 04 

+ 3 4 

w.  by  N. 

-2  07 

-3  35 

E.  by  s. 

+ 2 33 

+ 3 22 

w. 

— 2 30 

— 3 36 

E. 

+ 2 46 

+ 2 35 

w.  by  s. 

—2  21 

—3  8 

E.  by  N. 

-f2  27 

+ 2 27 

w.s.w. 

—2  12 

-2  35 

E.N.E. 

+ 1 58 

+ 1 53 

s.w.  by  w. 

— 2 21 

-2  1 

N.E.  by  E. 

+ 1 39 

+ 1 23 

s.w. 

— 1 33 

-1  33 

N.E. 

+ 1 13 

+ 1 8 

s.w.  by  s. 

— 1 05 

— 1 26 

N.E.  by  N. 

+ 1 11 

+ 1 I 

s.s.w. 

-0  47 

— 1 22 

N.N.E. 

-fO  34 

+ 0 30 

s.  by  w. 

-0  45 

-0  9 

N.  by  E. 

+ 0 27 

-0  27 

From  these  we  have  D=-}-l7^  and  E=+6';  also  at  the  Falk- 

land Islands,  and  —-054  at  the  Cape.  For  the  reasons  assigned  in  the  case  of  the 
Erebus,  I have  taken  — ’040  as  applicable  until  the  Terror  sailed  to  the  higher  lati- 
tudes in  December  1842,  and  have  then  increased  it  uniformly  and  progressively  with 
the  time  until  the  first  week  in  January  1843,  when  the  south  dip  was  greatest;  and 
from  this  date  until  the  arrival  at  the  Cape  I have  employed  —•054  (observed  at  the 
Cape),  which  was  the  greatest  observed  value  of  this  term. 

The  compass  employed  in  this  portion  of  the  Terror’s  voyage  was  made  by  Cum- 
mins, and  had  two  cards,  a light  and  a heavy  one,  the  latter  being-  used  exclusively  in 
very  bad  weather.  In  a memorandum  which  I received  from  Captain  Crozier,  it  is 
stated  that  the  index  errors  were  examined  at  the  observatory  in  the  Falkland  Islands 
on  the  23rd  of  August  1842,  and  found  to  require  corrections,  with  the  light  card  of 
+ 1°  13',  and  with  the  heavy  card  of  —0°  40'.  The  cause  of  these  errors  does  not 
appear  to  have  been  examined  either  during  the  voyage  or  after  the  return  to  England. 
The  error  of  the  light  card,  which  was  the  one  generally  used,  is  in  the  opposite  direc- 
tion to  the  error  assigned  to  the  compass  of  the  Erebus  examined  at  the  same  time ; 
and  it  is  remarkable  that  throughout  this  portion  of  the  voyage  in  which  the  two 
ships  were  always  in  company,  the  declinations  observed  in  the  Erebus  are  generally 
still  more  easterly  than  those  of  the  Terror  after  the  corrections  for  the  compass 
error  are  applied,  and  that  this  disagreement  would  be  greater  if  the  corrections  were 
not  so  applied.  I have  therefore  felt  the  less  hesitation  in  admitting  and  employing 
compass  errors  of  such  magnitude,  the  cause  of  which  does  not  appear  to  have  un- 
dergone investigation ; but  1 cannot  avoid  expressing  the  hope  that  as  the  state  of 

2 c 


MDCCCXLIX. 


190 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


the  compasses  supplied  to  Her  Majesty’s  navy  has  at  length  received  from  the  Ad- 
miralty the  attention  which  was  so  long  and  so  greatly  wanted,  and  since  a depart- 
ment has  been  expressly  instituted  for  their  proper  examination  and  care,  errors  of 
such  magnitude,  where  no  such  errors  need  exist,  may  no  longer  be  found  to  occur*. 

I would  also  take  this  occasion  to  remark,  that  in  examining  the  disturbance 
caused  by  the  ship’s  iron  at  the  spot  in  which  the  standard  compass  is  placed  by  the 
process  of  swinging  the  ship,  the  standard  compass  itself  should  be  employed,  and 
not,  as  appears  to  have  been  sometimes  done,  another  compass  substituted  for  that 
particular  occasion.  When  compass  errors  exist,  the  coefficient  A derived  from  the 
observations  with  one  compass  are  inapplicable  to  the  observations  of  another  compass 
having  a different  compass  error.  Also,  when  circumstances  permit,  it  is  preferable 
that  the  actual  disturbance  on  each  point  should  be  ascertained  independently  of  that 
on  other  points,  as  is  done  when  the  bearing  of  an  object  is  observed  whose  correct 
magnetic  bearing  is  known  or  subsequently  determined.  Disturbances  supposed  to 
be  ascertained,  by  comparing  azimuths  observed  on  each  point  with  the  means  of  the 
azimuths  observed  on  all  the  points,  are  liable  to  be  in  error  to  the  full  amount  of 
the  value  of  the  coefficient  A,  whether  that  value  arise  from  compass  error  or  from 
the  disturbing  influence  of  the  iron. 


Determinations  made  in  H.M.S.  Thunder,  in  a passage  from  Nassau,  New  Providence, 
to  England  in  1841,  hy  Captain  Edward  Barnett,  R.N. 

The  observations  in  the  Thunder  were  made  with  one  of  the  Admiralty  com- 
passes, fitted  as  a standard  compass.  The  disturbance  occasioned  by  the  iron  was 
examined  at  Nassau  in  March  1841,  immediately  after  the  arrival  of  the  ship  from 
England,  and  at  Gillingham  in  the  River  Medway,  about  the  1st  July  of  the  same 
year  on  her  return  to  England.  The  observations  were  as  follows,  viz. — 


Table  III. — Disturbance  of  the  Compass  in  H.M.S.  Thunder. 


Ship’s  head. 

Disturbances  towards  the  west. 

Ship’s  head. 

Disturbances  towards  the  w'est. 

Nassau. 

GilUngham. 

Nassau. 

Gillingham. 

c / 

o f 

o / 

o f 

N. 

-0  5 

— 0 15 

S. 

+ 0 23 

+ 0 38 

N.  by  w. 

+ 1 19 

+ 1 00 

s.  by  E. 

+ 0 1 

-1  17 

N.N.W. 

+ 1 16 

+ 1 59 

S.S.E. 

— 0 34 

— 1 25 

N.w.  by  N. 

+ 2 18 

+ 3 38 

s.E.  by  s. 

-0  43 

— 3 35 

N.W, 

+ 2 48 

+ 5 02 

S.E. 

— 1 22 

-4  2 

N.w.  by  w. 

+ 3 32 

+ 6 2 

s.E.  by  E. 

-2  1 

-4  23 

W.N.W. 

+ 3 53 

+ 6 6 

E.S.E. 

— 2 36 

-5  19 

w.  by  N. 

+ 3 45 

+ 6 12 

E.  by  s. 

-3  9 

— 5 50 

w. 

+ 3 52 

+ 6 15 

E. 

-3  19 

-6  16 

w.  by  s. 

+ 3 44 

+ 6 51 

E.  by  N. 

— 3 26 

— 5 44 

w.s.w. 

+ 3 21 

+ 5 15 

E.N.E. 

— 3 34 

—6  28 

s.w.  by  w. 

+ 2 59 

+ 5 42 

: N.E.  by  E. 

— 3 12 

-5  57 

s.w. 

+ 2 37 

+ 5 2 

N.E. 

-2  52 

— 4 46 

s.w.  by  s. 

+ 1 55 

+ 3 32 

N.E.  by  N. 

— 2 16 

— 3 48 

s.s.w. 

+ 1 52 

+ 2 40 

N.N.E. 

— 1 56 

— 2 51 

s.  by  w. 

+ 0 34 

+ 2 5 

N.  by  E. 

-0  27 

— 0 51 

* When  the  Erebus  left  England  the  prism  by  which  the  graduation  of  the  card  of  the  Admiralty  compasses 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


191 


From  these  we  obtain  A=+8';  D=-{~14';  E=  — 2';  B at  Nassau  =4-‘062,  and 
at  Gillingham  +*111  ; C at  Nassau  = — *006,  and  at  Gillingham  = — -007. 

From  Nassau  the  Thunder  passed  immediately  into  dips  on  the  coast  of  America 
higher  than  those  in  the  subsequent  portion  of  her  voyage,  or  than  the  dip  at  Gil- 
lingham. The  variable  part  of  the  disturbance  therefore,  probably,  increased  rapidly 
after  leaving  Nassau,  and  may  have  been  greater  whilst  the  ship  was  off  the  coast  of 
America  than  when  examined  at  the  termination  of  the  voyage.  Having  no  inter- 
mediate data,  however,  I have  not  ventured  to  exceed  the  maximum  observed  value 
of  v^B^-l-C^,  but  have  commenced  with  -l-‘062,  the  observed  value  at  Nassau  on  the 
1st  of  May,  and  increased  it  uniformly  with  the  time  to  -f-Tll,  the  observed  value 
at  Gillingham,  and  have  supposed  it  to  have  attained  the  latter  value  on  or  about 
the  1st  of  June,  when  the  ship  had  been  a fortnight  in  dips  exceeding  that  in  the 
Thames. 


Determinations  in  the  Prince  Regent  Transport,  on  the  passage  from  England  to  Canada 
in  1842,  hy  Lieutenant  {since  Captain)  J.  H.  Lefroy,  R.A. 

These  observations  were  made  by  Lieut.  Lefroy  when  proceeding  to  Canada  in 
1842  to  take  charge  of  the  Magnetic  Observatory  at  Toronto.  By  direction  of  the 
Hydrographer,  Lieut.  Lefroy  was  furnished  with  one  of  the  Admiralty  compasses, 
which  was  fixed  as  a standard  in  the  usual  manner.  The  Prince  Regent  was  swung 
at  Greenhithe  by  Captain  Johnson,  R.N.,  from  whom  I received  the  following  table 
of  deviations. 


Table  IV. — Disturbance  of  the  Compass  in  the  Prince  Regent  Transport. 


Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

o / 

o / 

O / 

N.  by  w. 

+ 0 45 

w.  by  s. 

+ 2 40 

s.  by  E. 

+ 0 05 

E.  by  N. 

— 2 00 

N.N.W. 

+ 1 55 

w.s.w. 

+ 2 20 

S.S.E. 

— 0 10 

E.N.E. 

— 1 45 

N.w.  by  N. 

+ 2 05 

s.w.  by  w. 

+ 2 05 

s.E.  by  s. 

-0  35 

N.E.  by  E. 

— 1 35 

N.W. 

+ 2 15 

s.w. 

+ 2 00 

S.E. 

— 0 35 

N.E. 

— 1 05 

N.W.  by,  w. 

+ 2 15 

s.w.  by  s. 

+ 1 35 

s.E.  by  E. 

-1  05 

N.E.  by  N. 

— 0 25 

W.N.W. 

+ 2 25 

s.s.w. 

+ 1 15 

E.S.E. 

— 2 00 

N.N.E. 

-0  15 

w.  by  N. 

+ 2 30 

s.  by  w. 

+ 1 05 

E.  by  s. 

-2  05 

N.  by  E. 

-0  10 

w. 

+ 2 25 

s. 

+ 0 25 

E. 

-2  05 

N. 

+ 0 05 

From  this  table  we  have  the  following  values  of  the  coefficients; — 


rA+27 

Permanent  coefficients  <^D-1-  5 

Ie  “{- 10 


Variable  coefficients 


fB-f--0389 

lc--oooi 


was  read,  had  a motion  of  adjustment  to  suit  different  eyes.  An  adjustment  of  this  nature  was  found  liable  to 
introduce  errors,  and  has  since  been  discontinued.  The  prisms  are  now  fixed,  immoveably,  at  a distance  from 
the  card  adapted  for  eyes  of  ordinary  vision. 


2 c 2 


192 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Circumstances  did  not  permit  the  Prince  Regent  to  be  swung  on  her  arrival  at 
Quebec,  and  we  have  no  other  means  of  assigning  the  variations  of  B (C  being  so 
small  that  it  may  be  disregarded)  than  by  assuming  it  to  have  varied  as  the  tangent 
of  the  dip,  which  increased  from  69°  in  the  Thames  to  79°  at  the  entrance  of  the 

*0389  tan 

River  St.  Lawrence.  Upon  this  supposition  B=  tan69°  ~ ^ ’ being  the 

dip  at  the  place  of  observation ; the  deviations  on  the  several  points  in  different  dips 
are  then  given  by 

sin  ^=27'+’9149  tan  & sin  ^'  + 5'  sin  2^'  + 10'  cos  2^', 
and  the  corrections  have  been  calculated  accordingly. 

They  appear  generally  to  reconcile  the  results  of  the  observations  on  the  different 
courses  very  satisfactorily. 

Determinations  in  H.M.S.  Philomel,  in  a passage  from  Monte  Video  to  England  in 

1846,  hy  Captain  Sulivan,  R.N. 

The  observations  of  Captain  Sulivan,  R.N.  were  made  in  a passage  from  Monte 
Video  to  England  in  1846  in  H.M.S.  Philomel.  The  error  of  the  compass  with  the 
ship’s  head  on  different  points  was  examined  at  Monte  Video  on  the  14th  of  September 
1844,  and  at  Plymouth  on  the  10th  of  June  1846,  as  follows  : — 


Table  V. 

Disturbance  of  the  Compass  in  H.M.S.  Philomel,  Monte  Video,  September  14,  1844. 


Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

j Ship’s  head. 

Disturbance 
towards  the 
west. 

N. 

N.  by  w. 

N.N.W. 

N.w.  by  N. 

N.W. 

N.W.  by  w. 

W.N.W. 

w.  by  N. 

— 0 57 

— 0 58 
-0  56 
-0  50 
-0  49 

— 0 50 
-0  40 
-0  43 

W. 

w.  by  S. 

w.s.w. 

s.w.  by  w. 

s.w. 

s.w.  by  s. 

s.s.w. 

s.  by  w. 

-0  40 
-0  50 

— 0 48 

— 0 38 
-0  40 
-0  25 

— 0 10 
+ 0 03 

s. 

s.  by  E. 

S.S.E. 

s.E.  by  s. 

S.E. 

s.E.  by  E. 
E.S.E. 

E.  by  s. 

+ 0 16 
+ 0 39 
+ 0 49 
+ 0 55 
+ 0 55 
+ 0 55 
+ 0 43 
+ 0 22 

i 

E. 

E.  by  N. 

E.N.E. 

1 N.E.  by  E. 

N.E. 

j N.E.  by  N. 

! N.N.i 

N.  by  E. 

+ 0 03 
— 0 12 
-0  26 
— 0 26 
— 0 22 
-0  29 
-0  45 
-0  55 

Plymouth,  June  10,  1846. 


Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
w'est. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

N. 

-d  20 

w. 

+ 1°  27 

S. 

— d 55 

E. 

-4  32 

N.  by  w. 

-0  19 

w.  by  s. 

+ 1 58 

s.  by  E. 

-1  09 

E.  by  N. 

— 4 36 

N.N.W. 

— 0 12 

w.s.w. 

+ 0 46 

S.S  E. 

— 1 37 

E.N.E. 

— 4 07 

N.W.  by  N. 

+ 0 30 

s.w.  by  w. 

+ 0 34 

S.E.  by  s. 

— 2 02 

N.E.  by  E. 

-4  34 

N.w. 

+ 0 52 

s.w. 

+ 0 33 

s.E. 

— 1 20 

N.E. 

—3  16 

N.w.  by  w. 

+ 2 13 

s.w.  by  s. 

+ 0 11 

s.E.  by  E. 

-1  27 

N.E.  by  N. 

—3  12 

W.N.W. 

+ 2 39 

s.s.w. 

-fO  05 

E.S.E. 

— 2 47 

N.N.E. 

—2  11 

w.  by  N. 

+ 2 30 

s.  by  w. 

-0  30 

E.  by  s. 

-3  37 

N.  by  E. 

-1  26 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


193 


The  mean  values  of  A,  D and  E,  from  the  preceding’  observations,  are  A=— 35' ; 
D=+26';  and  E=+2'.  B at  Monte  Video  = —‘0094;  and  at  Plymouth  +*0480; 
C— *0095  at  Monte  Video,  and  —-0031  at  Plymouth,  Assuming  the  values  of  B to 
have  been  the  same  when  the  Philomel  left  Monte  Video  for  England  in  April  1846 
as  when  she  was  swung  at  that  station  in  September  1844,  and  that  its  alteration  in 
the  passage  between  Monte  Video  and  Plymouth  was  uniform  in  respect  to  time,  we 
have  the  change  in  the  variable  term  of  the  correction  from  —*013  on  the  27th  of 
April  1846  to  +'048  on  the  following  10th  of  June;  being  at  the  rate  of  +"0014  for 
each  day.  The  corrections  have  been  applied  in  accordance  with  these  values  of  the 
coefficients. 

Determinations  in  the  Hudsons  Bay  Company s ship  the  Prince  Albert,  in  a passage 
from  England  to  Hudsons  Bay  and  back,  in  1846,  by  Lieut,  {since  Commander) 
T.  E.  L.  Moore,  R.N. 

The  observations  of  Lieut.  T.  E.  L.  Moore,  R.N.,  were  made  in  a voyage  from  the 
Thames  to  Moose  Fort  in  Hudson’s  Bay  and  back  in  the  summer  of  1846,  in  the 
Hudson’s  Bay  Company’s  ship  “ Prince  Albert,”  in  which  ship  Lieut,  Moore  embarked 
by  direction  of  the  Admiralty  for  the  purpose  of  making  magnetic  observations  in 
compliance  with  a recommendation  to  that  effect  from  the  Royal  Society. 

Lieut.  Moore  was  supplied  with  one  of  the  Admiralty  compasses  fixed  as  a standard 
compass;  the  ship  was  swung  at  Greenhithe  on  the  4th  of  June  1846  (before  her 
departure  from  the  Thames),  and  the  influence  of  the  iron  examined  on  the  eight 
principal  points  of  the  compass  as  follows  : — 


Table  VI. — Disturbance  of  the  Compass  in  the  Hudson’s  Bay  Company’s  ship 

Prince  Albert. 


Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

N. 

— 0 48 

w. 

+ 1 12 

S. 

+ 0°  20 

E. 

— \ 30' 

N.W. 

+ 1 00 

s.w. 

+ 0 40 

S.E. 

-0  40 

N.E. 

-1  10 

From  whence  we  obtain  A=  — 1 1' ; D=  + 12' ; E=  — 2' ; B=  -l-’0236  ; C=  — ’0099  ; 
the  (approximate)  inclination  being  68°  52'. 

On  the  26th  and  27th  of  August  following,  the  “ Prince  Albert”  being  then  at  the 
anchorage  at  Moose  Fort  in  Hudson’s  Bay,  her  head  was  placed  successively  on  seven 
of  the  same  points  (N.W.  being  omitted  on  account  of  difficulties  arising  from  the 
strength  of  the  tide),  and  the  bearing  of  an  object  ten  miles  distant  was  observed 
with  the  head  on  each  point. 


194 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


The  bearings  were  as  follows : — 


N. 

S.  65°  oo'  W. 

s. 

S.  65 

oo'  W. 

N.W. 

S.E. 

S.  63 

40  W. 

W. 

S.  67  00  W. 

E. 

S.  62 

00  W. 

s.w. 

S.  66  20  W. 

N.E. 

S.  62 

low. 

The  correct  magnetic  bearing  of  the  distant  object  from  the  ship  (or  that  which 
would  have  been  shown  by  the  ship’s  compass  with  her  head  on  each  of  the  points  if 
there  had  been  no  local  attraction)  does  not  appear  to  have  been  observed ; we  can 
obtain  from  the  observations  therefore  only  the  differences  of  the  bearings  on  the 
different  points.  From  these  we  have  the  half  difference  of  the  bearings  at  east  and 
west,  2°  30'=(nat.  sine  ’0436)  =\/ at  Moose  Fort,  where  the  (approximate)  in- 
clination =8]°’00.  Taking  the  value  of  the  at  Greenhithe  in  conformity 

with  the  observations  there  at  ’025,  and  assuming  that  its  variation  should  be  as  the 

tangent  of  the  inclination,  we  should  have -^^^^^^^^=’062  as  its  value  at  Moose 

Fort,  if  the  change  in  the  induced  magnetism  of  the  ship  had  kept  pace  with  the 
change  in  the  terrestrial  dip.  Here,  as  in  other  cases,  the  variation  of 
was  in  arrear  of  the  change  of  the  inclination,  since  the  observed  value  ’0436  corre- 
sponds to  a dip  of  only  77°  13'. 

The  whole  amount  of  the  deviation  in  the  “ Prince  Albert  ” is,  however,  so  extremely 
small  in  comparison  with  vessels  of  war  (the  extremes  at  the  east  and  west  points  not 
exceeding  at  the  Thames  and  2°^  at  Hudson’s  Bay),  that  we  should  obtain  a 
sufficient  approximation  to  the  true  variation  of  this  term,  whether  we  assumed  it  to 
vary  with  the  change  of  dip,  or  uniformly  with  the  lapse  of  time.  I have  taken  the 
latter  as  the  more  convenient  and  ready  mode  ; increasing  the  coefficient  from  -}-'025 
on  the  4th  of  June  ’0002  per  diem,  to  -l-’0436  on  the  26th  of  August,  and  diminish- 
ing it  at  the  same  rate  from  the  9th  of  September,  on  which  day  the  Prince  Albert 
began  to  lower  the  dip  on  her  homeward  voyage,  to  the  end  of  the  month  when  she 
entered  the  British  channel. 

Determinations  in  H.M.S.  Rattlesnake  in  a passage  from  England  to  the  Cape  of  Good 
Hope,  in  1847,  hy  Captain  Owen  Stanley,  R.N. 

The  influence  of  the  iron  on  the  Rattlesnake’s  standard  compass  was  examined  at 
Portsmouth,  November  30,  1846,  and  again  at  Port  Jackson  in  September  1847, 
circumstances  having  prevented  a satisfactory  repetition  of  the  experiments  during  a 
short  stay  at  the  Cape  of  Good  Hope. 

From  the  observations  at  Portsmouth  in  1846,  as  subjoined,  we  obtain  the  values 
ofA=— 30';  D=-l-25',  and  E= -1-5'. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


195 


Table  VH. — Disturbance  of  the  Compass  in  H.M.S.  Rattlesnake. 


Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

Ship’s  head. 

Disturbance 
towards  the 
west. 

N. 

-0  50 

W. 

+ 1°  30 

S- 

+ 0 30 

E. 

— 3 20 

X.N.W. 

+ 2 10 

vv.s.vv. 

+ 0 40 

S.S.E. 

— 1 50 

E.N.E. 

-4  30 

N.W. 

+ 3 40 

s.w. 

+ 1 50 

S.E. 

— 2 30 

N.E. 

— 3 50 

W.N.W. 

+ 2 33* 

s.s.w. 

+ 1 IG* 

E.S.E. 

— 2 35* 

N.N.E. 

— 2 20 

The  observations  at  Portsmouth  g-ive  B=  + ‘0565  with  a dip  (approximate)  of 
+ 68°  40' : by  their  repetition  at  Port  Jaekson  in  the  September  following  B was 
found  to  have  changed  to  — '0305,  with  a dip  (approximate)  of  —62°  48'.  The 
magnetism  of  the  iron  in  the  Rattlesnake  was  therefore,  for  the  most  part  at  least,  of 
the  nature  of  induced  magnetism  ; but  the  value  of  B in  this  case,  as  in  others  where 
the  ship  had  materially  ehanged  her  geographical  position,  was  in  arrear  on  her 
arrival  at  Port  Jackson  of  the  change  which  had  taken  place  in  the  terrestrial  dip ; 
it  eorresponded  to  a dip  of  — 54°  5'  instead  of  — 62°  48'.  Being  only  concerned  at 
present  with  the  observations  as  far  as  the  Cape  of  Good  Hope,  I have  taken  the 
V^B^+C^=+'056  at  Portsmouth,  which  is  its  value  derived  from  the  observations 
at  that  port ; and  having  no  materials  from  which  the  subsequent  variation  of  this 
term  might  be  more  correctly  computed,  I have  assumed  it  to  have  varied  as  the 
tangent  of  the  dip,  which  is  no  doubt  approximately  true. 


The  results  of  the  observations  which  have  been  thus  severally  described  are  con- 
tained in  the  general  table  No.  XII.  at  the  close  of  this  memoir,  arranged  in  zones  of 
latitude,  and  in  the  order  of  their  respective  longitudes.  This  table  also  contains  the 
correction  of  each  result  to  the  mean  epoch  of  January  1840.  The  original  manu- 
scripts of  the  unpublished  portion  of  the  observations  from  w+ich  these  results  are 
derived,  together  with  tabular  abstracts  containing  the  details  of  the  corrections 
applied  for  the  ship’s  iron,  will  be  deposited  in  the  Hydrographic  Office. 

The  subjoined  Table,  No.  VHI.,  contains  the  particulars  of  the  groups  into  which 
the  results  have  been  formed.  The  mean  declinations  at  the  points  of  intersection, 
shown  in  the  final  column  of  the  table,  constitute  the  elements  from  whieh  the  de- 
clination lines  in  the  map  are  derived ; the  lines  having  been  drawn  in  accordance 
with  them,  with  only  such  slight  deviations  as  were  indispensable  to  preserve  an 
interconformity  between  the  lines  in  a few  instances  where  it  was  obvious  that  the 
elements  themselves  were  slightly  discordant  with  each  other. 

* Interpolated. 


196 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


Table  VIII. — Elements  of  the  Declination  Lines. 


Intersections. 

Observations  employed 

Number  of 
additional 
observa- 
tions. 

Total  nura- 

Mean  declination 

Lat. 

Long. 

Between  the 
latitudes  of 

Between  the 
longitudes  of 

her  of  ob- 
servations. 

at  the  point  of 
intersection. 

62-5 

285*0 

60-0  and  65-0 

280-0  and  290-0 

7 

O / 

55  17 

62*5 

290*0 

60-0  and  65-0 

280-0  and  300-0 

12 

56  48 

60-0 

290*0 

50*0  and  70-0 

285-0  and  295-0 

8 

49  07 

60-0 

295*0 

58-5  and  62-5 

290-0  and  300-0 

5 

52  20 

60'0 

355*0 

58-0  and  62-0 

330-0  and  0-0 

12 

29  01 

57'5 

310*0 

54-0  and  6 1-0 

302-5  and  317*5 

6 

46  52 

57-5 

315*0 

55-0  and  60-0 

305-0  and  325*0 

7 

45  22 

57-3 

320*0 

55-0  and  60-0 

305*0  and  335*0 

10 

43  38 

57*5 

325*0 

35-0  and  60*0 

315-0  and  335-0 

1 

8 

42  05 

57-5 

330*0 

53-0  and  60-0 

320-0  and  340-0 

10 

39  55 

57‘5 

335*0 

56-0  and  59*0 

320-0  and  350  0 

10 

37  29 

57-5 

340*0 

55*0  and  60-0 

325-0  and  353-0 

1 

16 

34  59 

57*5 

345*0 

55*0  and  60-0 

336-0  and  354-0 

10 

32  35 

57-5 

350*0 

55*0  and  60-0 

345-0  and  355-0 

12 

30  20 

57-3 

355*0 

53-0  and  60-0 

*352*5  and  337*5 

12 

27  56 

57-3 

357*3 

54*0  and  6 1*0 

355-0  and  0-0 

13 

26  58 

55-0 

300*0 

49*0  and  6 1-0 

297-5  and  302-5 

4 

11 

40  48 

55-0 

305*0 

50-0  and  60-0 

302-5  and  307*5 

2 

11 

41  37 

55*0 

310*0 

50*0  and  60*0 

303*0  and  317*0 

1 

12 

41  42 

55-0 

315*0 

30*0  and  60*0 

305*0  and  325*0 

2 

12 

41  54 

55-0 

320*0 

50*0  and  60*0 

310-0  and  330-0 

12 

41  14 

55-0 

325*0 

50-0  and  60*0 

320-0  and  330-0 

7 

39  50 

55-0 

330*0 

50*0  and  60*0 

320*0  and  340*0 

13 

37  56 

.55‘0 

335*0 

30*0  and  60*0 

325-0  and  345-0 

2 

13 

35  42 

55-0 

340*0 

50-0  and  60-0 

330-0  and  350-0 

1 

11 

33  51 

55-0 

345*0 

50-0  and  60-0 

.339*0  and  351-0 

1 

7 

31  45 

55*0 

350*0 

50-0  and  60-0 

345*0  and  355*0 

1 

12 

29  33 

55-0 

355*0 

52*5  and  57*3 

350-0  and  0*0 

4 

24 

27  17 

55-0 

0*0 

52-5  and  57*5 

357*5  and  2*5 

3 

12 

24  54 

52-5 

350*0 

50*0  and  35-0 

347*5  and  352*5 

8 

28  41 

52-3 

335*0 

50-0  and  55-0 

352*5  and  357*5 

1 

8 

26  15 

52-5 

0*0 

50-0  and  55*0 

357*5  and  2*5 

12 

23  50 

30-0 

280*0 

48  0 and  52-0 

279*0  and  281*0 

4 

9 01 

50-0 

295-0 

49-0  and  51-0 

292*5  and  297*5 

2 

13 

25  09 

50-0 

300-0 

47-5  and  52*5 

297*5  and  302*5 

11 

29  49 

50-0 

305-0 

45-0  and  55*0 

302*5  and  307*5 

1 

11 

32  45 

50-0 

325-0 

47-0  and  53-0 

319-0  and  331*0 

1 

8 

34  32 

50-0 

330.0 

46-0  and  54-0 

325*0  and  335-0 

1 

8 

33  53 

50-0 

335-0 

42-5  and  57-3 

330-0  and  340-0 

2 

23 

31  52 

50-0 

340-0 

42*5  and  57*5 

335-0  and  345-0 

2 

24 

30  21 

50-0 

345-0 

42-5  and  57*5 

340-0  and  350*0 

2 

21 

28  52 

50-0 

350-0 

47-5  and  32-5 

345*0  and  355*0 

2 

15 

27  14 

50-0 

353-0 

45-0  and  35-0 

352*5  and  357*5 

13 

25  22 

47-3 

290-0 

46-5  and  48*5 

285*5  and  291*5 

1 

18 

16  10 

47-3 

295-0 

43-0  and  50-0 

292*5  and  297*5 

28 

20  50 

47-5 

300-0 

45-0  and  50-0 

297*5  and  302*5 

12 

25  09 

47-3 

305-0 

45-0  and  50-0 

300-0  and  310-0 

1 

7 

28  24 

47-3 

325-0 

42-5  and  52-3 

322*5  and  327*5 

9 

31  41 

47-3 

330-0 

43-0  and  50-0 

325*0  and  335*0 

2 

7 

31  02 

47-5 

335-0 

45*0  and  50-0 

330-0  and  340-0 

12 

29  44 

47-3 

340-0 

45-0  and  30-0 

335-0  and  345-0 

2 

16 

29  14 

47-3 

345-0 

45-0  and  50-0 

340-0  and  350-0 

1 

11 

27  50 

47*3 

350-0 

45-0  and  50-0 

345-0  and  355-0 

1 

14 

26  11 

47*3 

355-0 

45-0  and  50-0 

350-0  and  0*0 

2 

13 

24  34 

45*0 

285-0 

43-5  anil  46-5 

283-0  and  287*0 

2 

15 

7 54 

45*0 

290-0 

40-0  and  30-0 

289*0  and  291*0 

2 

27 

13  08 

A 


Ti 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC, 


197 


Table  VIII.  (Continued.) 


Intersections. 

Observations  employed 

Number  of 
additional 
observa- 
tions. 

Total  num- 
ber of  ob- 
servations. 

Mean  Declination 
at  the  point  of 
intersection. 

Lat. 

Long. 

Between  the 
Latitudes  of 

Between  the 
Longitudes  of 

4^0 

295-0 

42-5  and  47-5 

292-5  and  297*5 

14 

0 / 

17  34 

45-0 

300-0 

42-5  and  47-5 

297*5  and  302-5 

1 

7 

20  55 

45-0 

305-0 

40-0  and  50-0 

300-0  and  310-0 

9 

24  05 

45-0 

310  0 

40-0  and  50-0 

305-0  and  315-0 

8 

26  16 

45-0 

320-0 

43-0  and  47-0 

315-0  and  325-0 

1 

10 

28  23 

45-0 

325-0 

42-5  and  47-5 

320-0  and  330-0 

1 

10 

29  04 

45-0 

330-0 

42-5  and  47-5 

325-0  and  335-0 

1 

10 

28  29 

45-0 

335-0 

40-0  and  50-0 

330-0  and  340-0 

2 

21 

27  40 

45-0 

340-0 

40-0  and  50-0 

335-0  and  345-0 

« • • 

20 

27  08 

45-0 

345-0 

40-0  and  50-0 

342-5  and  347-5 

1 

11 

26  18 

42-5 

285-0 

39-0  and  46-0 

284-0  and  286-0 

3 

18 

5 36 

42-5 

290-0 

40-0  and  45-0 

288-0  and  292  0 

2 

18 

9 54 

42*5 

295-0 

39-0  and  46-0 

290-0  and  300-0 

15 

14  12 

42-5 

300-0 

39-0  and  46-0 

290-0  and  310  0 

20 

17  12 

42-5 

315-0 

40-0  and  45-0 

310-0  and  320-0 

10 

24  20 

42-5 

320-0 

40-0  and  45-0 

315-0  and  325-0 

14 

25  54 

42-5 

325-0 

40-0  and  45-0 

320-0  and  330-0 

14 

26  47 

42-5 

330-0 

40-0  and  45-0 

325-0  and  335-0 

2 

11 

26  08 

42'5 

335-0 

40-0  and  45*0 

330-0  and  340-0 

2 

9 

25  49 

40-0 

285-0 

37-5  and  42*5 

282-5  and  287-5 

15 

4 16 

40-0 

290-0 

37-5  and  42-5 

287-5  and  292-5 

11 

7 34 

40-0 

320-0 

35-0  and  45-0 

315-0  and  325-0 

22 

22  57 

40*0 

325-0 

35-0  and  45-0 

322  5 and  327-5 

19 

24  03 

40-0 

330-0 

35-0  and  45-0 

325-0  and  335-0 

26 

24  37 

40-0 

335-0 

35-0  and  45*0 

330-0  and  340  0 

1 

20 

24  37 

40-0 

340-0 

37-0  and  43-0 

335-0  and  345-0 

2 

8 

24  03 

40-0 

345-0 

35-0  and  45-0 

340-0  and  350-0 

1 

11 

23  37 

40-0 

360-0 

35-0  and  45-0 

355-0  and  5-0 

1 

18 

20  10 

37-5 

330-0 

35-0  and  40-0 

325-0  and  335-0 

18 

23  25 

37-5 

335  0 

35-0  and  40-0 

330-0  and  340-0 

2 

14 

23  25 

35-0 

285-0 

30-0  and  40-0 

280-0  and  290-0 

15 

1 23 

35-0 

320-0 

32-5  and  37-5 

317-5  and  322-5 

10 

18  58 

35-0 

325-0 

30-0  and  40-0 

322-5  and  327*5 

4 

22 

20  24 

35*0 

345-0 

32-5  and  37-5 

340-0  and  350-0 

5 

22  45 

35*0 

350-0 

32-5  and  37-5 

347-5  and  352-5 

7 

21  50 

35-0 

355-0 

32-5  and  37-5 

350-0  and  360-0 

12 

20  23 

30-0 

280-0 

25-0  and  35-0 

277-5  and  282-5 

5 

— 3 58 

30-0 

320-0 

27-5  and  32-5 

315-0  and  325-0 

21 

16  01 

30-0 

325-0 

25-0  and  35-0 

322-5  and  327-5 

1 

20 

17  54 

30-0 

345-0 

25-0  and  35-0 

340-0  and  350-0 

20 

22  00 

25-0 

285-0 

20-0  and  30-0 

280-0  and  290-0 

10 

— 2 36 

25-0 

320-0 

20-0  and  30-0 

315-0  and  325-0 

21 

12  38 

25-0 

325-0 

20-0  and  30-0 

320-0  and  330-0 

24 

14  59 

25-0 

330-0 

22-5  and  27-5 

325-0  and  335-0 

3 

14 

16  51 

25-0 

340  0 

22-5  and  27*5 

337-5  and  342-5 

1 

12 

20  02 

25-0 

342-5 

20-0  and  30-0 

340-0  and  345  0 

22 

20  07 

22-5 

340-0 

20-0  and  25-0 

338-5  and  341-5 

14 

19  36 

20-0 

285-0 

15-0  and  25'0 

280-0  and  290-0 

11 

- 3 29 

20-0 

290-0 

17-5  and  22-5 

280-0  and  300-0 

13 

- 2 08 

20-0 

320-0 

15-0  and  25-0 

317-5  and  322-5 

9 

10  27 

20-0 

325-0 

15-0  and  25-0 

320-0  and  330-0 

10 

12  48 

20-0 

330-0 

15-0  and  25-0 

325-0  and  335-0 

15 

15  04 

20-0 

335-0 

17-5  and  22-5 

330-0  and  340-0 

14 

17  27 

20-0 

340-0 

17-0  and  23-0 

337-5  and  342-5 

14 

19  15 

15-0 

300-0 

12-5  and  17-5 

297-5  and  302-5 

4 

- 0 55 

15-0 

325-0 

10-0  and  20-0 

320-0  and  330-0 

11 

11  32 

2 D 


MDCCCXLIX. 


198 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


Table  VIII.  (Continued.) 


Intersections. 

Observations  employed 

Number  of 
additional 
observa- 
tions. 

Total  num- 

Mean  Declination 

Lat. 

Long. 

Betvpeen  the 
Latitudes  of 

Between  the 
Longitudes  of 

her  of  ob- 
servations. 

at  the  point  of 
intersection. 

15-0 

336-0 

12-5  and  17'5 

325-0  and  335-0 

15 

13  51 

15-0 

335-0 

12-5  and  17-5 

330-0  and  340-0 

23 

16  05 

15-0 

340-0 

10-0  and  20-0 

337-5  and  342-5 

3 

14 

18  15 

10-0 

330-0 

5-0  and  15-0 

326-0  and  334-0 

15 

12  53 

10-0 

335-0 

7-5  and  12-5 

332-5  and  337-5 

15 

15  02 

10-0 

340-0 

7-5  and  12-5 

337*5  and  342-5 

1 

9 

17  11 

10-0 

345-0 

7-5  and  12-5 

342-5  and  347-5 

1 

10 

18  57 

5-0 

300-0 

0-0  and  10-0 

296-0  and  304-0 

10 

— 3 56 

5-0 

330-0 

2-5  and  7‘5 

327-5  and  332-5 

1 

8 

11  57 

5-0 

335-0 

2-5  and  7*5 

332-5  and  337-5 

12 

14  20 

5-0 

340-0 

2-5  and  7"5 

337-5  and  342-5 

3 

15 

16  21 

5-0 

345-0 

0-0  and  10-0 

340-0  and  350-0 

17 

18  21 

5-0 

350-0 

2-5  and  7-5 

347-5  and  352-5 

... 

5 

19  34 

5-0 

355-0 

2-5  and  7*5 

. 350-0  and  360-0 

2 

10 

20  06 

5-0 

0-0 

2-5  and  7-5 

355-0  and  5-0 

1 

12 

20  11 

5-0 

5-0 

0-0  and  10-0 

0-0  and  10-0 

12 

19  58 

0*0 

330-0 

+ 2-5  and  — 2-5 

327-5  and  332-5 

1 

16 

11  01 

0*0 

335-0 

+ 3-0  and  — 3-0 

331-0  and  339-0 

1 

14 

14  12 

0*0 

340-0 

+ 3-0  and  — 3-0 

335-0  and  345-0 

1 

19 

16  24 

— 2-5 

320-0 

0-0  and  — 5-0 

312-5  and  327-5 

6 

4 58 

— 5-0 

325-0 

0-0  and  —10-0 

322-0  and  328-0 

2 

12 

7 36 

— 5-0 

330-0 

— 2-5  and  — 7*5 

327-5  and  332-5 

3 

19 

10  40 

— 5-0 

335-0 

— 1-0  and  — 9*0 

332-5  and  337-5 

7 

13  58 

- 5-0 

340-0 

— 1-0  and  — 9*0 

335-0  and  345-0 

1 

14 

16  12 

— 5-0 

345-0 

0-0  and  —10-0 

342-5  and  347-5 

2 

15 

18  26 

— 10-0 

325-0 

- 7-5  and  -12-5 

322-5  and  327-5 

1 

9 

7 08 

— 10*0 

327-5 

— 7-5  and  —12-5 

325-0  and  330-0 

14 

8 37 

-10-0 

330-0 

— 7*5  and  —12-5 

327-5  and  332-5 

1 

17 

10  00 

-10-0 

340-0 

— 5-0  and  —15-0 

335-0  and  345-0 

10 

15  43 

-10*0 

345-0 

— 7-5  and  —12-5 

342-5  and  347-5 

1 

10 

18  08 

-15*0 

322-5 

— 12-0  and  —18-0 

321-0  and  324-0 

3 

30 

4 23 

— 15-0 

327-5 

— 12-0  and  —18-0 

325-0  and  330-0 

1 

16 

7 31 

— 15-0 

330-0 

— 10-0  and  —20-0 

328-0  and  332-0 

14 

8 56 

— 15-0 

345-0 

-10-0  and  —20-0 

342-5  and  347-5 

1 

11 

18  10 

— 15-0 

350-0 

— 14-0  and  — I6-O 

347-5  and  352-5 

15 

20  38 

— 15-5 

352-5 

— 13-0  and  — 17-O 

350-0  and  355-0 

17 

21  35 

-17-5 

355-0 

— 15-0  and  —20-0 

352-5  and  357-5 

2 

19 

22  40 

-20-0 

320-0 

— 17-0  and  —23-0 

317-5  and  322-5 

2 

17 

1 53 

-20-0 

325-0 

— 17-0  and  —23-0 

324-0  and  326-0 

3 

12 

4 48 

— 20-0 

330-0 

-15-0  and  —25-0 

327-5  and  332-5 

12 

8 02 

— 20-0 

345-0 

— 15-0  and  — 25-0 

342-5  and  347-5 

1 

10 

17  15 

-20-0 

350-0 

— 15-0  and  — 25-0 

347-5  and  352-5 

1 

14 

20  53 

-20*0 

355-0 

— 17-0  and  —23  0 

350-0  and  0-0 

2 

13 

22  50 

— 22-5 

5-0 

— 18-0  and  —27-0 

2-0  and  8-0 

5 

25  28 

-25-0 

315-0 

—20-0  and  —30-0 

313-0  and  317-0 

16 

— 2 22 

— 25*0 

320-0 

— 22-5  and  —27-5 

317-5  and  322-5 

1 

13 

0 57 

-25-0 

325-0 

— 22-0  and  —28-0 

322-0  and  328-0 

7 

3 47 

— 25-0 

330-0 

— 20-0  and  — 30-0 

325-0  and  335-0 

13 

6 51 

-25*0 

335-0 

— 23-0  and  —27-0 

330-0  and  340-0 

1 

9 

9 53 

— 25-0 

340-0 

— 20-0  and  —30-0 

335-0  and  345-0 

14 

13  08 

— 25-0 

345-0 

— 20-0  and  —30-0 

341-0  and  349-0 

13 

16  43 

— 25-0 

350-0 

— 20-0  and  —30-0 

346-0  and  354-0 

11 

20  25 

— 25-0 

7-5 

—20-0  and  —30-0 

360-0  and  00-0 

1 

9 

26  18 

— 30-0 

300-0 

—27-0  and  -33-0 

297-5  and  302-5 

4 

-12  00 

-30-0 

315-0 

-27-5  and  —32-5 

310-0  and  320-0 

12 

- 3 26 

-30-0 

320-0 

— 25-0  and  —35-0 

316-0  and  324-0 

15 

- 0 26 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


199 


Table  VIII.  (Continued.) 


Intersections. 

Observations  employed 

Number  ol 
additional 
observa- 
tions. 

Total  num 
ber  of  ob- 
servations 

Mean  Declination 
at  the  point  of 
intersection. 

Lat. 

Long. 

Between  the 
Latitudes  of 

Between  the 
Longitudes  of 

— 30-0 

335-0 

— 26-0  and  —34-0 

330-0  and  340-0 

2 

10 

9°  00 

-30-0 

340-0 

— 55-0  and  —35-0 

335-0  and  345-0 

16 

12  13 

-30-0 

345-0 

— 25-0  and  —35-0 

340-0  and  350-0 

2 

16 

15  34 

-30-0 

350-0 

— 25-0  and  —35-0 

345-0  and  355-0 

2 

12 

18  40 

— 30*0 

353-0 

— 27-5  and  —32-5 

350-0  and  00-0 

2 

10 

21  34 

-30-0 

0-0 

—28-0  and  —32-0 

358-0  and  02-0 

7 

23  39 

— 30-0 

10-0 

— 25-0  and  —35-0 

5-0  and  15-0 

1 

18 

27  22 

— 35-0 

300-0 

—31-0  and  —39-0 

297-0  and  303-0 

16 

— 13  15 

— 33-0 

305-0 

-34-0  and  -36-0 

302-5  and  307-5 

1 

15 

— 10  38 

— 35-0 

310-0 

— 30-0  and  —40-0 

307-5  and  312-5 

15 

— 7 41 

-35*0 

325-0 

-31-0  and  —39-0 

320-0  and  330-0 

... 

6 

1 39 

— 33-0 

333-0 

-30-0  and  -40-0 

330-0  and  340-0 

2 

11 

7 44 

— 33-0 

340-0 

— 30-0  and  —40-0 

336-0  and  344-0 

11 

10  47 

— 33-0 

330-0 

— 30-0  and  —40-0 

343-0  and  357-0 

2 

13 

17  03 

— 33-0 

355-0 

-30-0  and  —40-0 

351-0  and  359-0 

2 

10 

19  51 

— 33*0 

0-0 

— 30-0  and  —40-0 

355-0  and  05-0 

18 

22  31 

-33-0 

5-0 

— 30-0  and  -40-0 

0-0  and  10-0 

1 

10 

25  10 

— 33-0 

10-0 

— 32-0  and  —38-0 

6-0  and  14-0 

2 

14 

26  50 

— 33-0 

15  0 

— 30-0  and  —40-0 

13-0  and  17-O 

22 

27  50 

— 35-0 

17-5 

— 30-0  and  -40-0 

16-0  and  19-0 

16 

28  51 

— 40-0 

297-5 

— 38-0  and  —42-0 

297-0  and  298-0 

2 

13 

— 16  02 

— 40-0 

300-0 

— 37-0  and  —43-0 

298-0  and  302-0 

2 

15 

-14  30 

— 40-0 

305-0 

— 37-0  and  -43-0 

300-0  and  310-0 

14 

— 12  13 

— 42-3 

297-5 

— 41-0  and  44-0 

296-0  and  299-0 

2 

11 

-16  42 

-42-5 

300-0 

— 40-0  and  43-0 

298-5  and  301-0 

2 

9 

-15  17 

—43-0 

295-0 

— 42-5  and  — 47-5 

294-0  and  296-5 

1 

15 

— 18  34 

— 47-5 

292-5 

— 45-0  and  -50-0 

292-0  and  293-0 

2 

14 

—20  00 

-47-5 

297-5 

-45-0  and  — 30-0 

295-0  and  300-0 

3 

10 

-18  19 

—30-0 

292-5 

— 47-0  and  -53-0 

291-5  and  293-0 

18 

— 20  49 

— 30-0 

295-0 

— 47-5  and  —32-5 

294-0  and  296-5 

3 

12 

-20  15 

— 30-0 

297-5 

-47-5  and  —52-5 

296-0  and  299-5 

1 

9 

-19  15 

— 50-0 

10-0 

— 47-0  and  —53-0 

5-0  and  15-0 

6 

— 23  35 

— 32-3 

290-0 

— 50-0  and  —33-0 

289-5  and  290-0 

4 

14 

— 22  48 

— 32-3 

292-5 

-30-0  and  —55-0 

292-0  and  293-0 

2 

10 

—21  50 

— 32*3 

295-0 

— 50-0  and  —53-0 

291-0  and  299-0 

59 

— 21  04 

— 32*3 

297-5 

— 50-0  and  — 55-0 

295-0  and  300-0 

29 

— 20  15 

—32-3 

300-0 

— 51-0  and  — 54-0 

299-0  and  301-0 

14 

-19  39 

— 32-3 

302-5 

— 50-0  and  —53-0 

301-0  and  304-0 

18 

— 18  33 

— 35-0 

290-0 

-34-0  and  -36-0 

289-0  and  291-0 

1 

8 

-23  41 

— 53-0 

292-5 

— 54-0  and  — 56-0 

292-0  and  293-0 

2 

15 

— 23  16 

— 33-0 

295-0 

— 54-0  and  — 56-0 

294-0  and  296-0 

1 

18 

—22  31 

-33-0 

305-0 

— 53-0  and  -57-0 

303-0  and  307-0 

13 

-18  17 

— 37-5 

307-5 

— 55-0  and  — 6O-O 

305-0  and  310-0 

9 

— 18  25 

— 37*5 

332-5 

— 56-0  and  —59-0 

350-0  and  355-0 

6 

— 10  58 

-60-0 

307-5 

— 56-0  and  — 64-0 

305-0  and  310-0 

12 

-19  31 

—62-3 

330-0 

-62-0  and  —63-0 

327-0  and  333-0 

4 

— 5 50 

-62-3 

335-0 

—60-0  and  — 65-0 

332-0  and  338-0 

6 

— 2 32 

—62-3 

345-0 

—60-0  and  — 65-O 

343-0  and  347-0 

... 

7 

4 20 

-63-0 

302-5 

— 64-0  and  —66-0 

301-0  and  304-0 

... 

18 

-23  23 

-63-0 

305-0 

— 64-0  and  —66-0 

304-0  and  306-0 

2 

16 

-21  54 

—63-0 

317-5 

— 64-0  and  — 66-0 

316-0  and  319-0 

6 

— 14  07 

—63*0 

350-0 

— 60-0  and  —70-0 

348-0  and  352-0 

8 

7 01 

— 67'3 

347-5 

— 65-0  and  — 70-0 

345-0  and  350-0 

8 

4 17 

—70-0 

343-0 

-69-0  and  -71-0 

343-0  and  347-0 

... 

4 

2 27 

2 D 2 


200 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


General  Table  of  the  Declination  in  the  Atlantic.— \t  may  possibly  be  found  con- 
venient for  the  purposes  of  navigation,  that  the  books  which  contain  a compendium 
of  the  tables  requisite  to  be  used  at  sea,  should  include  a general  table  of  the  mag- 
netic Declination  at  a certain  epoch  for  a convenient  number  of  geographical  posi- 
tions, with  auxiliary  tables  furnishing  the  means  of  readily  computing  the  Declina- 
tion for  intermediate  positions,  and  for  other  years.  The  subjoined  Tables,  Nos.  IX. 
and  X.,  have  been  formed  for  the  purpose  of  supplying  what  has  frequently  appeared 
to  me  a desideratum  in  this  respect.  No.  IX.  is  a general  table  of  the  Declination  in 
the  Atlantic  for  January  1840,  at  the  intersection  of  every  fifth  degree  of  latitude 
and  longitude  between  60°  north  and  60°  south  latitude,  taken  from  the  maps  which 
accompany  this  memoir.  Should  this  table  be  adopted  in  future  editions  of  any  of 
the  very  useful  compendiums  referred  to,  auxiliary  tables  may  be  readily  computed 
and  added,  containing  the  factors  in  longitude  and  latitude  for  facilitating  the  cal- 
culation of  the  Declination  corresponding  to  intermediate  geographical  positions; 
whilst  by  means  of  Table  X.  the  values  of  the  Declinations  in  Table  IX.  may  be 
adapted  approximately  to  any  other  year  for  which  the  Declination  may  be  required. 
The  numbers  which  it  contains  are  the  values  of  the  annual  secular  change  of  the 
Declination,  which  being  multiplied  by  the  interval  of  years  from  the  date  to  which 
the  table  corresponds  {i.  e.  January  1840),  observing  to  prefix  the  sign  + to  the 
interval  (in  years)  if  the  Declination  is  required  for  a subsequent  year  to  1840,  or 
the  sign  — if  required  for  an  earlier  year,  will  give  the  correction  to  be  applied  for 
the  difference  of  epoch. 

The  values  of  the  secular  change  in  Table  X.  are  derived  from  the  comparison  of 
the  maps  which  accompany  this  memoir  with  the  map  of  the  Declination  in  1787? 
published  originally  (with  the  observations  on  which  it  was  based)  in  Hansteen’s 
Magnetismus  der  Erde,  and  republished  in  this  country  by  myself  in  the  Report  of 
the  British  Association  for  the  Advancement  of  Science  in  1835.  The  table  conse- 
quently represents  the  average  annual  secular  change  which  has  taken  place  in  the 
fifty-three  years  antecedent  to  1840.  But  it  will  be  remembered  that  the  secular 
change  in  any  particular  locality  is  by  no  means  a constant  quantity ; and,  although 
over  a large  proportion  of  the  area  of  the  Atlantic,  there  is  reason  to  believe  that  the 
annual  change  is  still  continuing  at  a rate  which  does  not  materially  differ  from  the 
average  of  the  last  fifty  years,  yet  there  are  parts,  (as  for  example,  in  the  vicinity  of  the 
British  Islands,  and  of  the  Cape  of  Good  Hope,)  where  the  secular  change  has  latterly 
been  obviously  undergoing  a considerable  alteration.  Tables  formed  as  these  have 
been,  will  therefore  require  to  be  reformed  from  time  to  time ; the  general  table  by 
fresh  observations,  and  the  table  of  secular  change  by  a comparison  of  the  maps 
founded  on  those  observations  with  those  now  given.  The  time  that  may  be  allowed 
to  elapse  before  the  present  tables  are  thus  reformed  will  probably  depend  less  on  the 
interests  of  navigation  and  science,  than  on  the  degree  of  attention  with  which  these 
interests  may  be  regarded  by  the  authorities  of  the  Admiralty  in  times  to  come. 


LLNES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


201 


But  whenever  it  may  be  clone,  it  may  be  expected  that  the  observations  of  that  period 
will  be  much  more  accordant  with  each  other,  and  with  nature,  than  those  which 
have  been  at  my  disposal ; in  consequence  of  the  general  adoption,  that  we  may 
reasonably  anticipate  will  then  have  taken  place,  of  the  practice  of  correcting  for  the 
deviation  in  the  pointing  of  the  compass  occasioned  by  the  ship’s  iron,  and  which  the 
increased  employment  of  iron  in  the  equipment  of  vessels  and  the  magnitude  of  the 
errors  occasioned  thereby,  already  render  in  a great  number  of  instances  absolutely 
indispensable.  Those  who  know,  as  matter  of  history,  the  difficulties  with  which  the 
first  introduction  of  lunar  observations  and  chronometers  had  to  contend,  can  con- 
fidently look  forward  to  a period  when  the  practice  of  correcting  the  errors  of  the 
compass  shall  have  become  general  amongst  naval  officers  at  least,  if  not,  as  may  be 
hoped,  amongst  merchant  seamen  also ; especially  since  in  the  form  in  which  the 
corrections  are  now  placed,  no  other  preliminary  knowledge  is  required  for  this  pur- 
pose than  that  of  the  four  first  rules  in  arithmetic,  with  due  attention  to  the  signs  by 
which  the  errors  and  corrections  are  characterised. 


202  LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


The  Declinations  marked  thus  f are  interpolated  in  the  absence  of  observations.  East  Declination  is  characterised  by  the  sign  Where  no  sign  is  prefixed  the 

Declination  is  West.  ^ 6 i 


Table  X.— Annual  Secular  Change  in  the  Magnetic  Declination,  on  the  average  of  fifty-three  years  antecedent  to 
January  1840,  taken  to  the  nearest  half-minute.  The  sign  + in  this  table  implies  that  the  secular  change  in  the  period 
referred  to  was  increasing  westerly,  or  decreasing  easterly  Declination  ; and  the  sign  — implies  the  change  to  have  been 
decreasing  westerly,  or  increasing  easterly  Declination. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


203 


oo 

vD 

O 

ID 

O 

ID 

o 

ID 

© 

ID 

© 

ID 

© 

»D 

© 

ID 

o 

ID 

© 

ID 

© 

ID 

© 

ID 

© 

-3 

CD 

iD 

4D 

CO 

CO 

©1 

©4 

T 

©< 

1 

Dl 

1 

CO 

1 

© 

Tp 

1 

Tp 

ID 

! 

ID 

© 

1 

© 

Tp 

© 

© 

ID 

© 

© 

’ 

• 

© 

© 

© 

© 

© 

© 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

ID 

© 

© 

ID 

© 

© 

© 

© 

© 

ID 

© 

© 

© 

o 

>6 

©^ 

CO 

ID 

© 

© 

© 

cb 

© 

© 

© 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

O 

C> 

© 

© 

ID 

© 

ID 

© 

ID 

ID 

© 

© 

© 

04 

© 

Srs 

•st^ 

6 

O 

O 

©J 

© 

CO 

ID 

© 

© 

cb 

© 

© 

© 

© 

© 

© 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

o 

o 

o 

ID 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

04 

© 

o 

o 

o 

o 

o 

CO 

CO 

ID 

CD 

cb 

© 

© 

© 

© 

© 

© 

© 

© 

-L. 

i 

1 

+ 

+ 

+ + + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

o 

o 

o 

ID 

o 

O 

© 

CC 

© 

ID 

© 

© 

ID 

© 

© 

© 

© 

© 

ID 

04 

© 

6 

o 

o 

6 

O 

©4 

©1 

©1 

©1 

© 

© 

© 

© 

© 

— 

© 

© 

© 

© 

© 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

J_ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

»D 

ID 

o 

ID 

©1 

CO 

CD 

© 

© 

©1 

© 

© 

CO 

© 

© 

© 

© 

© 

04 

O 

O 

©^ 

— 

©? 

CO 

CO 

Tp 

ID 

ID 

© 

© 

© 

© 

© 

05 

© 

© 

CO 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

CO 

CO 

‘D 

O 

o 

o 

CO 

© 

© 

© 

© 

ID 

ID 

© 

© 

© 

CO 

ID 

ID 

© 

tT» 

© 

©^ 

©« 

©4 

CO 

»b 

i-b 

ID 

ID 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

cb 

CO 

+ + 

+ 

+ 

+ + 

+ 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ + 

+ 

u 

CD 

o 

o 

o 

CO 

o 

© 

©1 

»D 

CO 

CO 

ID 

©1 

© 

© 

© 

Tp 

© 

© 

ID 

© 

© 

$ 

o 

CO 

ID 

ID 

CD 

© 

CD 

© 

© 

© 

© 

© 

© 

© 

© 

© 

a; 

c; 

s 

Fi 

CO 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ + + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

o 

o 

ID 

o 

Tp 

O 

© 

ID 

© 

© 

© 

©4 

© 

CO 

CO 

ID 

© 

© 

ID 

© 

ID 

o 

CO 

'I' 

CD 

O 

ID 

ID 

CD 

CD 

CD 

© 

© 

© 

05 

© 

© 

© 

© 

© 

© 

© 

© 

CO 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+- 

-f 

+ 

+ 

+ + + 

+ 

+ 

o 

ID 

o 

o 

ID 

ID 

CD 

o 

©^ 

ID 

o 

CO 

©^ 

© 

eq 

ID 

ID 

Tp 

© 

ID 

© 

© 

ID 

o 

o 

; 

CD 

CO 

CD 

CD 

CD 

ID 

© 

© 

© 

© 

© 

© 

© 

© 

© 

© 

tH 

© 

© 

© 

lb 

o 

'o 

CO 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

u 

V3 

©^ 

»D 

ID 

O 

O 

O 

ID 

© 

ID 

© 

© 

© 

© 

ID 

© 

© 

© 

CM 

(01 

ID 

© 

© 

ID 

•rs 

\ 

CO 

CD 

00 

*>• 

CD 

CO 

ID 

© 

CD 

© 

© 

© 

© 

© 

© 

© 

© 

© 

cb 

CO 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

CO 

o 

o 

©1 

05 

ID 

© 

© 

© 

ID 

© 

© 

© 

ID 

© 

© 

© 

ID 

© 

»D 

04 

o 

' ] 

C5 

05 

CD 

ID 

Tp 

ID 

lb 

© 

© 

CO 

© 

© 

© 

© 

© 

© 

cb 

ID 

cb 

CO 

+ 

+ 

+ 

+ 

+ 

+ + 

+ 

+ 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

©^ 

©^ 

o 

O 

O 

CO 

©1 

© 

© 

© 

© 

© 

© 

© 

ID 

© 

© 

»D 

© 

*D 

Tp 

C5 

o 

CO 

CD 

lb 

TP 

Tp 

Tp 

lb 

© 

© 

© 

© 

cb 

cb 

cb 

© 

(M 

CO 

+ 

+ 

+ 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

ID 

CO 

ID 

o 

00 

©1 

ID 

o 

© 

#>» 

tN, 

Tp 

© 

© 

© 

Tp 

IN. 

© 

o 

"©1 

o 

o 

CD 

ID 

ID 

Tp 

CO 

©^ 

© 

© 

ID 

— 

CO 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

CO 

o 

o 

o 

o 

O 

CO 

© 

CO 

o 

CO 

ID 

© 

ID 

ID 

ID 

© 

Tp 

o 

'‘CO 

o 

lb 

lb 

CO 

©1 

©1 

©1 

©1 

»D 

© 

ID 

ID 

Tp 

© 

— 

CO 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

CO 

cq 

©1 

©^ 

ID 

o 

o 

©1 

© 

© 

ID 

© 

Tp 

© 

© 

© 

© 

ID 

o 

6i 

C5 

CD 

Tp 

Tp 

Tp 

©1 

©< 

©^ 

tH 

© 

cb 

Tp 

© 

— 

CO 

+ 

+ 

+ + 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

o 

o 

ID 

©^ 

CD 

©^ 

© 

© 

ID 

© 

ID 

© 

ID 

ID 

ID 

CO 

©^ 

©1 

©^ 

©1 

TT 

(01 

04 

© 

cq 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

+ 

CO 

CD 

©1 

©4 

©1 

CO 

ID 

o 

©< 

© 

© 

ID 

o 

©1 

CO 

©1 

©^ 

©^ 

©1 

+ 

+ 

+ 

+ + + 

+ 

+ 

+ 

+ 

+ 

+ 

o 

CO 

CO 

CD 

o 

O 

ID 

ID 

o 

GO 

•vcb 

6 

o 

fIm 

©^ 

A 

1 

+ 

1 

1 

1 

+ 

+ 

+ 

+ 

1 

- 

ID 

ID 

o 

O 

ID 

1 

CO 

»D 

©4 

o 

O 

+ 

1 

1 

1 

1 

+ 

oo 

ID 

o 

ID 

o 

ID 

O 

ID 

© 

ID 

© 

ID 

© 

ID 

© 

ID 

© 

»D 

© 

© 

© 

ID 

© 

ID 

* 

CD 

ID 

ID 

TP 

CO 

CO 

©1 

©1 

<01 

(01 

© 

© 

Tp 

ID 

ID 

© 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

1 

204 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Comparison  with  M.  Gauss's  Theory. — As  many  persons  may  be  desirous  of  seeing 
the  result  of  a comparison  of  the  Declinations  computed  by  M.  Gauss’s  general 
theory,  with  those  derived  from  observation  over  a field  of  considerable  extent,  I 
have  subjoined  in  Table  XI.  in  degrees  and  decimals  of  a degree,  the  differences  of 
Declination  at  the  intersections  of  every  five  degrees  of  latitude  and  longitude. 
The  sign  — signifies  that  the  theoretical  Declinations  are  mot  e easterly  (i.  e.  greater 
east  or  less  west  Declination)  than  the  observed  ; and  the  sign  + that  the  theo- 
retical are  more  westerly  (i.  e.  greater  west  or  less  east  Declination)  than  the  ob- 
served. 

It  must  be  remembered  that  the  coefficients  of  M.  Gauss’s  theory  in  their  present 
numerical  values  do  not  profess  to  be  more  than  a first  approximation  ; that  they 
rest  on  maps  of  the  phenomena  drawn  indeed  from  observation,  but  in  which  care 
was  not  always  taken  to  use  only  observations  of  a definite  epoch  ; that  the  points 
of  the  globe  in  which  the  elements  of  the  theory  rest  upon  the  observed  pheno- 
mena are  only  eighty-four  points  on  the  whole  surface  of  the  globe,  viz.  twelve 
points  on  seven  parallels ; no  point  being  taken  in  a more  southern  parallel  than  20° 
south  latitude ; and  lastly,  that  the  coefficients  are  limited  to  terms  of  the  fourth 
order. 

On  the  other  hand,  it  will  be  remembered  that  the  Declination  is  the  easiest,  and 
has  been  by  far  the  most  frequently  observed,  of  the  three  magnetic  elements ; that 
from  a very  early  period  maps  of  the  Declination,  particularly  in  the  Atlantic,  and 
professing  to  be  adapted  to  definite  epochs,  have  been  in  much  request  on  account 
of  their  use  in  navigation  ; and  that  consequently  it  might  naturally  be  expected 
that  the  differences  between  the  theory  and  observation  should  be  less  in  the  com- 
parison here  instituted,  than  might  be  the  case  in  parts  of  the  globe  where  the  ele- 
ments of  the  theory  have  had  a less  direct,  or  a less  satisfactory  derivation. 

The  differences  of  greatest  amount  which  appear  in  this  comparison  are  those 
over  the  north-west  portion  of  the  Atlantic,  amounting  to  from  five  to  nearly  eight 
degrees  generally  between  the  meridian  of  Newfoundland  and  the  United  States, 
(meridians  of  287°  to  307°,  or  53°  to  73°  west  longitude),  in  the  well-traversed 
parallels  from  45°  to  50°  N. ; and  increasing  to  1 8°  and  upwards  in  the  latitude  of  60° 
in  the  vicinity  of  Hudson’s  Strait,  where  the  correct  value  of  the  declination  has 
been  well  known  for  several  years  by  the  observations  of  the  different  British  expedi- 
tions of  discovery.  In  the  southern  Atlantic,  where,  as  already  remarked,  the  data 
of  observation  on  which  the  theoretical  coefficients  are  based  have  not  been  taken 
from  a higher  latitude  than  20° S,,  there  appears  a tendency  to  systematic  differences; 
in  excess  (or  too  small  easterly  declinations)  on  the  west  side  of  the  Atlantic,  and  in 
defect  (or  too  small  westerly  declinations)  on  the  east  side  of  the  Atlantic. 

A discrepancy  deserving  of  notice  in  the  theoretical  lines  (i.  e in  the  lines  of  mag- 
netic Declination  as  they  may  be  drawn  from  calculation  with  the  present  numerical 
elements  of  M.  Gauss’s  theoi'y),  is  in  the  value  of  the  remarkable  isogonic  line,  the 


(or  less  easterly)  than  the  observed  Declinations. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


205 


MLCCCXLIX 


206 


LINES  OF  xMAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


branches  of  which  form  the  limits  of  the  four  great  systems  of  isogonic  lines,  viz.  of 
the  four  great  systems  which  prevail  respectively  in  the  N.W.,  N.E.,  S.W.  and  S.E. 
directions,  and  have  one  isogonic  line  common  to  them  all,  the  branches  of  which 
meet  at  a common  point  of  junction  or  intersection  near  the  west  coast  of  Africa, 
and  not  far  from  the  terrestrial  equator.  The  theoretical  value  of  this  line  is  22°  13' W.; 
whereas  its  true  value  is  certainly  not  more  than  between  19°  and  20°,  and  it  appears 
to  have  been  in  the  year  1840  nearly  midway  between  those  values.  Had  the  theo- 
retical value  been  in  defect  instead  of  in  excess,  the  difference  might  have  been 
ascribed  to  an  effect  of  secular  change ; in  which  case  M.  Gauss’s  map  might  be 
supposed  to  represent  an  earlier  state  of  the  phenomena  than  that  of  the  year  1840. 
But  the  fact  is  otherwise ; the  theoretical  value  of  the  line  in  question  is  in  excess, 
although  its  actual  value  has  been  progressively  increasing  since  the  earliest  record 
of  the  phenomena,  and  was  greater  in  1848  than  in  any  antecedent  year  since  the 
phenomena  have  been  observed.  The  theoretical  error  is  the  more  remarkable 
because  Mr.  Barlow’s  map  for  1833,  which  was  the  one  employed  by  M.  Gauss  for 
the  declination,  gives  the  value  of  that  element  correctly  at  20°  or  thereabouts,  at 
the  spot  where  M.  Gauss’s  theoretical  line  of  22°  13'  cuts  the  coast  of  Africa. 

The  form  of  the  lines  in  Mr.  Barlow’s  map  in  that  quarter  of  the  globe  is  indeed 
not  correct,  since  on  no  part  of  the  surface  of  the  earth  do  the  magnetic  lines  forh  in 
the  manner  there  represented,  and  which  is  very  different  from  the  intersection  of 
lines  of  equal  value  forming  four  branches  of  one  and  the  same  isogonic  line,  which 
is  the  character  of  the  remarkable  line  now  referred  to;  but  the  value  of  the  declina- 
tion on  that  part  of  the  African  coast  is  more  correct  in  Mr.  Barlow'’s  map  than  in 
M.  Gauss’s  theory,  which  is  partly  based  upon  it.  The  geographical  position  of  the 
intersection  is  also  given  by  M.  Gauss’s  theory  about  10°  of  longitude  too  much  to 
the  east.  The  secular  movement  of  the  intersection  is  to  the  west,  and  may  be 
estimated,  very  roughly,  at  about  10°  in  the  last  half-century. 

It  is  obvious  from  this  comparison  that  the  General  Theory  will  require  to  have 
its  numerical  coefficients  reconstructed  before  it  can  become  available  for  practical 
purposes ; and  that  those  who  desire  to  take  a correct  view  of  the  magnetic 
phenomena,  must  for  the  present  at  least,  have  recourse  to  the  maps  constructed 
directly  from  the  observations  themselves. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


207 


Table  XII. — Declinations  employed  in  the  Map,  corrected  to  the  epoch  of 

January.  1840. 


t in  the  column  of  remarks  signifies  that  the  Declination  has  been  corrected  for  the  effect  of  the  ship’s  iron. 


Observed 

Corree- 

Corrected 

Lat. 

Long. 

Date. 

Observer. 

Declina- 

tion  for 

Declina- 

Remarks. 

tion. 

Epoch. 

tion. 

Between  the  latitudes  of  65°  and  60°. 

o 

63 

18 

280 

41 

1846. 

Moore. 

0 

58 

21 

0 

— 1 

24 

56 

37 

At  seaf. 

63 

13 

282 

55 

1846. 

Moore. 

55 

28 

— 1 

24 

54 

31 

At  seat- 

63 

15 

284 

41 

1846. 

Moore. 

58 

54 

— 1 

24 

57 

30 

At  seaf. 

63 

19 

285 

40 

1846. 

Moore. 

60 

13 

— 1 

24 

58 

49 

At  seaf. 

62 

57 

287 

13 

1846. 

Moore. 

58 

56 

— 1 

24 

57 

32 

At  seaf. 

62 

47 

288 

27 

1846. 

Moore. 

58 

20 

— 1 

24 

56 

56 

At  seaf. 

61 

54 

289 

40 

1846. 

Moore. 

54 

49 

— 1 

24 

53 

25 

At  seaf. 

62 

13 

290 

47 

1846. 

Moore. 

59 

20 

— 1 

24 

57 

56 

At  seaf. 

61 

00 

294 

48 

1846. 

Moore. 

55 

56 

— 1 

24 

54 

32 

At  seaf. 

61 

34 

295 

46 

1846. 

Moore. 

58 

33 

— 1 

24 

57 

09 

At  seaf. 

60 

49 

296 

00 

1846. 

Moore. 

56 

22 

— 1 

24 

54 

58 

At  seaf. 

60 

58 

299 

00 

1846. 

Moore. 

55 

49 

— 1 

24 

54 

25 

At  seaf. 

64 

08 

338 

05 

1836. 

Lottin. 

43 

14 

+ 0 

22 

43 

36 

Reikiavik. 

62 

00 

354 

02 

1831.  Vidal. 

30 

50 

+ 0 

17 

31 

07 

Thorshavn. 

60 

09 

358 

53 

1838.  Ross. 

27 

09 

+0 

03 

27 

12 

Lerwick. 

60 

45 

359 

14 

1831. 

Vidal. 

28 

38* 

+ 0 

17 

28 

55 

Balta  Island. 

Between  the  latitudes  of  60°  and  50°. 

51 

15 

279 

04 

1846. 

Moore. 

12 

40 

+0 

18 

12 

58 

Moose  Factory. 

51 

18 

279 

16 

1846. 

Moore. 

10 

55 

+0 

18 

11 

13 

f On  shore,  entrance  of  Moose 
\ Harbour. 

51 

28 

279 

26 

1846. 

Moore. 

10 

41 

+ 0 

18 

10 

59 

At  seaf. 

51 

49 

279 

28 

1846. 

Moore. 

10 

05 

+ 0 

18 

10 

23 

At  seaf. 

50 

13 

293 

35 

1831. 

Bayfield. 

23 

34 

+ 0 

36 

24 

10 

Bay  of  Seven  Islands. 

50 

11 

293 

55 

1831. 

Bayfield. 

24 

08 

+ 0 

36 

24 

44 

Moisic  River. 

50 

17 

295 

58 

1831. 

Bayfield. 

25 

30 

+ 0 

51 

26 

21 

Mingan  Harbour. 

50 

03 

296 

07 

1842. 

Lefroy. 

26 

26 

-0 

15 

26 

05 

At  seaf. 

50 

14 

296 

49 

1832. 

Bayfield. 

27 

31 

+ 0 

50 

28 

21 

Betcliewun  Harbour. 

50 

14 

297 

48 

1832. 

Bayfield. 

28 

08 

+ 0 

52 

29 

00 

Nabosippe  River. 

50 

11 

298 

44 

1832. 

Bayfield. 

28 

47 

+ 1 

00 

29 

47 

Kegashka  Bay. 

50 

11 

299 

52 

1832. 

Bayfield. 

29 

22 

+ 1 

00 

30 

22 

Cape  Whittle. 

50 

33 

300 

43 

183.3. 

Bayfield. 

29 

33 

+ 0 

55 

30 

28 

Little  Mecattina. 

50 

44 

300 

59 

1833. 

Bayfield. 

30 

00 

+ 0 

58 

31 

00 

Grand  Mecattina. 

51 

16 

301 

47 

1834. 

Bayfield. 

31 

15 

+ 0 

55 

32 

10 

Mistanoque  Harbour. 

51 

27 

302 

33 

1834. 

Bayfield. 

32 

00 

+ 0 

56 

32 

56 

Belles  Amours  Harbour. 

51 

28 

302 

45 

18.34. 

Bayfield. 

32 

30 

+ 0 

59 

33 

29 

Bradore  Harbour. 

51 

28 

303 

03 

1833. 

Bayfield. 

32 

26 

+ 1 

05 

33 

41 

Forteaw  Bay. 

59 

55 

303 

20 

1846. 

Moore. 

52 

29 

— 1 

24 

51 

05 

At  seaf. 

51 

24 

303 

26 

1833. 

Bayfield. 

33 

30 

+ 1 

05 

34 

35 

Green  Island  in  Straits  of  Bellisle. 

51 

44 

303 

34 

1835. 

Bayfield. 

34 

30 

+ 0 

47 

35 

17 

Red  Bay. 

52 

00 

304 

09 

1835. 

Bav  field. 

35 

30 

+ 0 

48 

36 

18 

Chateau  Bay. 

52 

21 

304 

21 

1835. 

Bayfield. 

37 

30 

+ 0 

50 

38 

20 

Cape  St.  Lewis. 

58 

46 

307 

00 

1846. 

Moore. 

50 

05 

— 1 

21 

48 

44 

At  seaf. 

56 

49 

310 

26 

1846. 

Moore. 

45 

45 

— 1 

15 

44 

30 

At  seaf. 

57 

54 

310 

34 

1846. 

Moore. 

48 

45 

— 1 

15 

47 

30 

At  seaf. 

57 

42 

315 

57 

1846. 

Moore. 

47 

44 

— 1 

15 

46 

29 

At  seaf. 

54 

00 

316 

24 

Sept.  1846. 

Moore. 

44 

00 

— 1 

16 

42 

44 

At  seaf. 

57 

30 

319 

20 

1846. 

Moore. 

45 

28 

— 1 

11 

44 

17 

At  seaf. 

57 

21 

321 

05 

1846. 

Moore. 

44 

33 

— 1 

11 

43 

22 

At  seaf. 

52 

17 

321 

45 

Sept.  1846. 

Moore. 

39 

18 

— 1 

14 

38 

04 

At  seaf. 

* A mean  of  4 stations. 
2 E 2 


208 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  60 

^ and  50'^ 

(continued). 

O 

57 

05 

324 

10 

1846. 

Moore. 

O 

43 

16 

o 

— 1 

03 

0 

42 

/ 

11 

At  seaf. 

51 

47 

325 

00 

Sept.  1846. 

Moore. 

37 

40 

— 1 

08 

36 

32 

At  seaf. 

51 

10 

327 

09 

Sept.  1846. 

Moore. 

37 

43 

— 1 

00 

36 

43 

At  seaf. 

56 

25 

327 

15 

1846. 

Moore. 

40 

19 

-0 

45 

39 

34 

At  seaf. 

56 

15 

329 

18 

1846. 

Moore. 

40 

14 

-0 

45 

39 

29 

At  seaf. 

50 

14 

330 

46 

Sept.  1846. 

Moore. 

35 

55 

-0 

53 

35 

02 

At  seaf. 

56 

16 

333 

02 

1846. 

Moore. 

38 

18 

— 0 

26 

37 

52 

At  seaf. 

56 

00 

335 

06 

1846. 

Moore. 

36 

52 

— 0 

26 

36 

26 

At  seaf. 

55 

41 

336 

55 

1846. 

Moore. 

36 

26 

— 0 

26 

36 

00 

At  seaf. 

55 

53 

337 

05 

1846. 

Moore. 

35 

32 

— 0 

26 

35 

06 

At  seaf. 

56 

09 

338 

25 

1846. 

Moore. 

36 

20 

— 0 

26 

35 

54 

At  seaf. 

56 

19 

341 

08 

1846. 

Moore. 

34 

19 

-0 

22 

33 

57 

At  seaf. 

57 

43 

345 

08 

1846. 

Moore. 

32 

14 

-0 

16 

31 

58 

-At  seaf. 

58 

40 

349 

09 

1846. 

Moore. 

31 

35 

-0 

13 

31 

22 

At  seaf. 

51 

56 

349 

43 

Oct.  1838. 

Boss. 

28 

42 

-0 

06 

28 

36 

Valencia  Island. 

52 

02 

350 

30 

Oct.  1838. 

Ross. 

28 

11 

— 0 

06 

28 

05 

Killarney- 

53 

48 

350 

31 

Nov.  1838. 

Ross. 

29 

09 

— 0 

06 

29 

03 

Westport. 

52 

40 

351 

24 

Oct.  1838. 

Ross. 

28 

03 

— 0 

06 

27 

57 

Limerick. 

57 

49 

351 

28 

Oct.  1831. 

Vidal. 

30 

30 

— 0 

34 

29 

56 

St.  Kilda. 

51 

54 

351 

32 

Oct.  1838. 

Ross. 

27 

44 

-0 

06 

27 

38 

Cork. 

54 

14 

351 

32 

Nov.  1 838. 

Ross. 

29 

15 

-0 

06 

29 

09 

Markree. 

53 

14 

352 

07 

Oct.  1838. 

Ross. 

28 

03 

-0 

06 

27 

57 

Shannon  Harbour. 

53 

42 

352 

27 

Nov.  1838. 

Ross. 

28 

08 

— 0 

06 

28 

02 

Edgeworthstown. 

55 

08 

352 

35 

1831. 

Vidal. 

28 

28 

-0 

06 

28 

22 

Buncrana. 

54 

59 

352 

41 

Nov.  1838. 

Ross. 

28 

47 

-0 

06 

28 

41 

Londonderry. 

52 

15 

352 

52 

Oct.  1838. 

Ross. 

26 

44 

-0 

06 

26 

38 

Waterford. 

54 

21 

353 

21 

Nov.  1838. 

Ross. 

28 

08 

-0 

06 

28 

02 

Armagh. 

58 

15 

353 

36 

1846. 

Otter. 

27 

40 

-0 

06 

27 

34 

Stornaway. 

53 

21 

353 

45 

Oct.  1838. 

Ross. 

27 

35 

-0 

06 

27 

29 

Dublin. 

53 

21 

353 

45 

Jan.  1840. 

Lloyd. 

27 

30 

0 

00 

27 

30 

Dublin  Observatory. 

59 

05 

353 

53 

1831. 

Vidal. 

29 

41 

-0 

34 

29 

07 

Sulisker. 

59 

07 

354 

13 

1831. 

Vidal. 

29 

34 

— 0 

34 

29 

00 

Rona. 

58 

09 

354 

46 

1848. 

Otter. 

27 

59 

+ 0 

42 

28 

41 

Loch  Inver. 

58 

23 

354 

56 

1846. 

Otter. 

27 

34 

+0 

42 

28 

16 

Luxford. 

58 

15 

354 

57 

1846. 

Otter. 

27 

58 

+ 0 

42 

28 

40 

Gowan. 

50 

09 

355 

09 

1831. 

Austin. 

25 

25 

-0 

42 

24 

43 

Pendenuis  Castle. 

57 

28 

355 

49 

Aug.  1838. 

Ross. 

27 

59 

— 0 

06 

27 

53 

Inverness. 

57 

58 

356 

03 

Aug.  1838. 

Ross. 

27 

55 

-0 

06 

27 

49 

Golspie. 

58 

24 

356 

55 

Aug.  1838. 

Ross. 

27 

41 

-0 

06 

27 

35 

Wick. 

59 

00 

357 

02 

Aug.  1838. 

Ross. 

27 

47 

-0 

06 

27 

41 

Kirkwall. 

54 

55 

357 

16 

Sept.  1838. 

Ross. 

26 

15 

— 0 

06 

26 

09 

Carlisle. 

55 

35 

357 

29 

Jan.  1842. 

Brisbane. 

25 

27 

+ 0 

10 

25 

37 

Makerstoun  Observatory. 

58 

16 

357 

49 

1846. 

-Moore. 

26 

43 

+ 0 

42 

27 

25 

At  seaf. 

57 

09 

357 

55 

Julv  1838. 

Ross. 

26 

41 

-0 

06 

26 

35 

Aberdeen. 

54 

58 

358 

24 

Aug.  1 838. 

Ross. 

25 

20 

— 0 

06 

25 

14 

Newcastle. 

52 

57 

358 

52 

Mav  1838. 

Ross. 

24 

53 

— 0 

06 

24 

47 

Nottingham. 

53 

57 

358 

54 

Aprill838. 

Ross. 

25 

09 

— 0 

06 

25 

03 

York. 

54 

18 

359 

34 

May  1838. 

Ross. 

24 

32 

-0 

06 

24 

26 

Scarborough. 

54 

08 

359 

46 

May  1838. 

Ross. 

24 

39 

-0 

06 

24 

33 

Bridlington. 

51 

31 

359 

38 

Aprill838. 

Ross. 

23 

59 

-0 

06 

23 

53 

Bushey. 

53 

19 

0 

00 

May  1838. 

Ross. 

24 

26 

-0 

06 

24 

20 

Louth. 

51 

28 

0 

00 

1841. 

Airy. 

23 

16 

+ 0 

07 

23 

23 

Greenwich  Observatory. 

51 

56 

1 

13 

May  1838. 

Ross. 

23 

08 

— 0 

06 

23 

12 

Harwich. 

52 

56 

1 

19 

May  1838. 

Ross. 

23 

21 

— 0 

06 

23 

15 

Cromer. 

51 

23 

1 

23 

April  1838. 

Ross. 

22 

54 

— 0 

06 

22 

48 

Margate. 

52 

28 

1 

50 

May  1838. 

Ross. 

23 

00 

-0 

06 

22 

54 

Lowestotfe. 

50 

51 

4 

22 

.Jan.  1844.' 

Quetelet. 

21 

16 

+ 0 

32 

21 

48 

Brussels. 

59 

54 

10 

44 

Jan.  1840. 

Hansteen.  I 

19 

50 

0 

0 

19 

50 

Christiania. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


•209 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  50°  and  40°. 

0 

43 

40 

280 

38 

Jan.  1840.lRiddell. 

0 

1 

27 

O 

0 

00 

O 

1 

27 

Magnetic  Observatory,  Toronto. 

45 

36 

283 

07 

May  1843. 

Lefroy. 

5 

11 

+ 0 

05 

5 

16 

Fort  Portage. 

45 

29 

284 

12 

May  1843. 

Lefrov. 

6 

58 

+ 0 

05 

7 

03 

6 miles  below  Bytown. 

40 

08 

284 

17 

May  1846. 

U.S.  Coast  Survey. 

4 

22 

-0 

04 

4 

18 

Whitehill. 

40 

05 

284 

26 

June  1846. 

U.S.  Coast  Survey. 

3 

13 

-0 

04 

3 

09 

Fort  Delaware. 

45 

37 

284 

48 

May  1843. 

Lefroy. 

6 

58 

+ 0 

05 

7 

03 

Alfred  Township. 

45 

37 

285 

05 

May  1843. 

Lefroy. 

7 

28 

+ 0 

05 

7 

33 

Point  aux  Chenes. 

45 

36 

285 

28 

May  1843. 

Lefrov. 

8 

41 

+ 0 

05 

8 

46 

Carillon. 

45 

36 

285 

38 

Mav  1843. 

Lefroy. 

8 

26 

+ 0 

05 

8 

31 

On  the  Ottawa. 

40 

43 

285 

59 

1844. 

Renwick. 

6 

13 

— 0 

02 

6 

11 

Columbia  College. 

40 

28 

286 

00 

Jan.  1844. 

U.S.  Coast  Survey. 

5 

51 

-0 

02 

5 

49 

Sandy  Harbour. 

45 

30 

286 

25 

1842. 

Lefroy. 

8 

58 

0 

00 

8 

58 

Montreal. 

45 

32 

286 

26 

1834. 

Bayfield. 

8 

00 

0 

00 

8 

00 

Montreal. 

40 

53 

286 

29 

1844. 

Renwick. 

6 

54 

— 0 

02 

6 

52 

Oyster  Bay. 

45 

00 

286 

39 

Oct.  1845. 

Boundary  Survev. 

11 

28 

0 

00 

11 

28 

Rouse’s  Point. 

45 

19 

286 

42 

1842. 

Lefroy. 

11 

22 

0 

00 

11 

22 

St.  John’s. 

46 

06 

286 

39 

1830. 

Bayfield. 

10 

30 

0 

00 

10 

30 

Stone  Island. 

46 

03 

287 

00 

1830. 

Bayfield. 

11 

00 

0 

00 

11 

00 

Sorel. 

46 

03 

287 

00 

1842. 

Lefroy. 

11 

23 

0 

00 

11 

23 

Sorel. 

41 

15 

287 

05 

Sept.  1845. 

U.S.  Coast  Survey. 

6 

17 

-0 

06 

6 

11 

Newhaven. 

46 

14 

287 

16 

1828. 

Bayfield. 

11 

15 

+ 0 

06 

11 

21 

Lake  St.  Peter. 

46 

17 

287 

18 

1835. 

Bayfield. 

10 

53 

+ 0 

02 

10 

55 

Point  du  I.ac. 

44 

16 

287 

23 

1829-1830 

Graham. 

12 

26 

+ 0 

10 

12 

36 

Montpelier. 

46 

19 

287 

£4 

1842. 

Lefroy. 

11 

58 

-0 

10 

11 

57 

Three  Rivers. 

45 

53 

287 

26 

1842. 

Lefroy. 

12 

28 

— 0 

01 

12 

27 

Drummondville. 

46 

25 

287 

36 

1835. 

Bayfield. 

12 

52 

+0 

02 

12 

54 

Isle  Bigot. 

41 

06 

287 

38 

1845. 

Renwick. 

7 

14 

-0 

06 

7 

08 

Sandy  Point. 

45 

00 

287 

47 

Nov.  1845. 

Boundary  Survey. 

11 

33 

0 

00 

11 

33 

Stanstead. 

44 

02 

287 

55 

Sept.  1830. 

Graham. 

7 

32 

+ 0 

10 

7 

42 

Haverhill. 

43 

56 

288 

05 

Sept.  1830. 

Graham. 

9 

08 

+ 0 

10 

9 

18 

Warren. 

41 

20 

288 

05 

1842. 

U.S.  Coast  Survey. 

7 

38 

— 0 

06 

7 

32 

Stonington. 

46 

40 

288 

06 

Aug  1845. 

Bayfield. 

12 

52 

+ 0 

02 

12 

54 

Platon  Point. 

43 

49 

288 

07 

Sept.  1830. 

Graham. 

9 

38 

+ 0 

10 

9 

48 

West  Rumney. 

43 

45 

288 

18 

Sepl.  1 830. 

Graham. 

8 

32 

+ 0 

10 

8 

42 

Plymouth. 

45 

01 

288 

30 

Dec.  1845. 

Graham. 

12 

22 

0 

00 

12 

££ 

Canaan  Corner. 

44 

43 

288 

31 

Sept.  1830. 

Graham. 

7 

53 

+ 0 

10 

8 

03 

Lake  Winninsissiogee. 

46 

49 

288 

44 

1842. 

Lefroy. 

14 

12 

— 0 

02 

14 

10 

Quebec,  Artillery  Barracks. 

45 

15 

288 

46 

May  1845. 

Boundary  Survey. 

12 

17 

— 0 

17 

12 

00 

Prospect  Hill. 

46 

49 

288 

47 

1831-1836 

Bayfield. 

14 

14 

+ 0 

06 

14 

20 

Quebec,  Wolfe’s  Monument. 

45 

15 

288 

47 

Oct.  1845. 

Boundary  Survey. 

12 

00 

-0 

18 

11 

42 

Observatory,  Connecticut  River. 

42 

23 

288 

52 

1840. 

Lowering  and  Bond. 

9 

18 

0 

0 

9 

18 

Observatory,  Cambridge,  U.S. 

45 

18 

288 

55 

June  1845. 

Boundary  Surve}’. 

13 

20 

-0 

17 

13 

03 

Near  the  Highland  Boundary  Line. 

41 

19 

288 

59 

1844. 

Renwick. 

7 

29 

-0 

05 

7 

24 

Croton  Point. 

45 

20 

289 

05 

June  1845. 

Boundary  Survey. 

13 

30 

-0 

17 

13 

13 

Arnold’s  River. 

41 

38 

289 

05 

Aug.  1845. 

U.S.  Coast  Survey. 

8 

57 

— 0 

08 

8 

49 

Fort  Point. 

45 

26 

289 

12 

July  1845. 

Boundary  Survey. 

13 

10 

-0 

17 

12 

53 

Dead  River. 

41 

28 

289 

14 

Aug.  1846. 

U.S.  Coast  Survey. 

9 

10 

-0 

10 

9 

00 

Tarpaulin  Town. 

43 

05 

289 

15 

July  1844. 

Boundary  Survey. 

9 

47 

-0 

14 

9 

33 

Boiling  Rock. 

45 

30 

289 

16 

Oct.  1844. 

Boundary  Survey. 

13 

20 

— 0 

17 

13 

03 

Near  the  Highland  Boundary. 

45 

32 

289 

18 

Sept.  1844. 

Boundary  Survey. 

13 

30 

-0 

16 

13 

14 

Near  the  Highland  Boundary. 

45 

37 

289 

23 

Sept.  1844. 

Boundary  Survey. 

13 

37 

-0 

16 

13 

21 

Near  the  Highland  Boundary. 

41 

29 

289 

24 

Aug.  1846. 

U.S.  Coast  Survey. 

8 

50 

— 0 

10 

8 

40 

Indian  Hill. 

47 

08 

289 

28 

1842. 

Lefroy. 

14 

00 

-0 

04 

13 

56 

At  seaf. 

47 

04 

289 

28 

1831. 

Bayfield. 

14 

28 

+ 0 

19 

14 

47 

Crane  Island. 

45 

42 

289 

32 

Sept.  1844. 

Boundary  Survey. 

13 

50 

— 0 

16 

13 

34 

On  the  Flighland  Boundary. 

47 

25 

289 

34 

1831, 

Bayfield. 

15 

17 

+ 0 

19 

15 

36 

Isle  aux  Condres. 

210 


I.INES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Loi 

g- 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  50 

0 

0 

03  1 

(continued). 

O 

45 

39 

289 

36 

Aug.  1844. 

Boundary  Survey. 

0 

14 

07 

0 

-0 

16 

0 

13 

51 

Taschereau’s. 

47 

12 

289 

38 

1831. 

Bayfield. 

14 

49 

+ 0 

19 

15 

08 

Stone  Pillar. 

47 

20 

289 

42 

1842. 

Lefrov. 

14 

16 

— 0 

06 

14 

10 

At  seaf. 

42 

03 

289 

48 

Sept.  1 835. 

Graham. 

9 

20 

+ 0 

11 

9 

31 

Provincetown. 

46 

25 

289 

57 

Nov.  1844. 

Boundary  Survey. 

15 

02 

-0 

17 

14 

45 

Astron.  Station,  S.W'.  branch  of 
the  St.  John’s  River. 

48 

09 

290 

16 

1829. 

Bavfield. 

17 

35 

+ 0 

24 

17 

59 

Tadousac. 

47 

53 

290 

18 

1833. 

Bayfield. 

17  20 

+ 0 

16 

17 

36 

Brandy  Pots. 

47 

51 

290 

26 

1831. 

Bayfield. 

17 

36 

+ 0 

19 

17 

55 

River  du  Loup. 

46 

57 

290 

33 

Sept.  1844. 

Boundary  Survey. 

16 

29 

-0 

16 

16 

13 

Astron.  Station.  Big  Black  River. 

48 

12 

290 

51 

1829. 

U.  S.  Coast  Survey. 

17 

34 

+ 0 

24 

17 

58 

Razade  Islands. 

48 

37 

290 

53 

1831. 
f Sept.l 

Bayfield. 

17 

36 

+ 0 

19 

17 

55 

Port  Neuf. 

47 

14 

290 

59 

-N  &Oct.  > 

1 1843.  1 

Boundary  Survey. 

17 

24 

-0 

18 

17 

06 

Astron.  Station,  River  St.  Francis. 

47 

11 

291 

04 

Oct.  1842. 

Boundary  Survey. 

17 

03 

-0 

13 

16 

50 

Astron.  Station,  near  the.  mouth  of 
the  River  St.  Francis. 

48 

25 

291 

11 

1830. 

Bayfield. 

17 

29 

+ 0 

24 

17 

53 

Bic  Island. 

47 

16 

291 

16 

Oct.  1842. 

Boundary  Survey. 

17 

58 

-0 

13 

17 

45 

Savage  Island. 

48 

55 

291 

22 

1831. 

Bayfield. 

18 

48 

+ 0 

22 

19 

10 

Bersimis  Point. 

47 

17 

291 

37 

Oct.  1842. 

Boundary  Survey. 

17 

58 

-0 

13 

17 

45 

Bourgeois’s  House. 

46 

31 

291 

38 

Aug.  1841. 

Boundary  Survey. 

16 

43 

-0 

07 

16 

36 

Mouth  of  the  Massardis  River. 

47 

12 

291 

46 

Aug.  1842. 

Boundary^  Survey. 

17 

53 

-0 

12 

17 

41 

Lake  Cleveland. 

47 

19 

291 

50 

Aug.  1843. 

Boundary  Survey. 

18 

06 

-0 

17 

17 

49 

Mouth  of  Green  River. 

41 

06 

292 

04 

June  1841. 

Barnett. 

10 

08 

— 0 

03 

10 

05 

At  seaf. 

46 

46 

292 

10 

July  1841. 

Boundary  Survey. 

17 

27 

-0 

07 

17 

20 

Near  Fort  Fairfield. 

49 

18 

292 

12 

1830. 

Bayfield. 

19 

57 

+ 0 

26 

20 

23 

St.  Nicholas  Harbour. 

46 

59 

292 

13 

Nov.  1841. 

Boundary'  Survey. 

17 

43 

— 0 

08 

17 

35 

Peacock  Hill. 

46 

47 

292 

13 

Oct.  1841. 

Boundary  Survey'. 

17 

28 

— 0 

08 

17 

20 

Aroostook  Hill. 

46 

38 

292 

13 

Oct.  1841. 

Boundary  Survey. 

17 

15 

-0 

08 

17 

07 

Blue  Hill. 

46 

07 

292 

13 

Dec.  1840. 

Boundary  Survey. 

16 

09 

-0 

04 

16 

05 

Parks  Hill. 

45 

57 

292 

13 

Oct.  1840. 

Boundary  Survey. 

16 

00* 

-0 

03 

15 

57 

Astron.  Station  of  the  Boundary- 
Commission. 

49 

04 

292 

17 

1842. 

Lefroy. 

21 

37 

— 0 

08 

21 

29 

At  seaf. 

49 

19 

292 

37 

1830. 

Bayfield. 

20 

13 

+ 0 

28 

20 

41 

Port  de  Monts. 

49 

38 

292 

49 

1832. 

Bayfield. 

21 

35 

+ 0 

24 

21 

59 

Egg  Island. 

49 

06 

293 

14 

1830. 

Bayfield. 

21 

27 

+ 0 

28 

21 

55 

Cape  Chatte. 

41 

04 

293 

19 

June  1841. 

Barnett. 

11 

55 

-0 

03 

11 

52 

At  seaf. 

49 

36 

293 

21 

1842. 

Lefroy. 

22 

30 

-0 

08 

22 

22 

At  seaf. 

* “ This  observation  was  made  at  the  Astronomical  Station  on  the  due  north  line,  4578  feet  north  of  the  Monu- 


ment marking  the  source  of  the  River  St.  Croix.  On  a Cedar  Post  8 inches  square  erected  in  1817  by  the 
Boundary  Commissioners  under  the  Treaty  of  Ghent,  at  the  source  of  the  River  St.  Croix,  is  the  following  in- 
scription : — ‘ Variation  13°  51'-2  by  one  instrument,  and  14°  by  another,’  signed  by  ‘ Col.  Joseph  Bouchette, 
H.B.M.  Surveyor,  and  John  Johnson,  U.S.  Surveyor,  31st  July,  1817.’  The  Declination  in  1840,”  (as  given 
above,)  “is  derived  from  the  following  observations  made  by  Lieut. -Col.  Graham  and  Lieut.  T.  J.  Lee  : — 


Oct.  18  and  19,  1840  < 


y Mean  16  00 


"By  Draper’s  compass  No.  4 16  04' 

By  Stancliffe’s  compass  No.  2 15  58 

By  Draper  Nicole’s  compass  No.  1 15  59 

By  Draper  Nicole’s  compass  No.  2 16  01 

By  Potter’s  compass  No.  3 16  01 

-By  Variation  Transit  15  59  J 

“ It  appears  from  the  comparisons  of  the  two  determinations,  one  in  1817  and  the  other  in  1840,  that  the  West 
Declination  has  increased  2°  04''5  in  23'22  years;  or  at  an  average  rate  of  5'‘3  a year.” — Lieut.-Col.  Graham, 
MSS. 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


211 


Table  Xll.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Decbna- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  50"^ 

and  40° 

(continued). 

O 

48 

04 

293 

38 

1839. 

Bayfield. 

20 

15  ' 

0 

+ 0 

02 

0 

20 

/ 

17 

Dalhousie  Island. 

48 

05 

293 

52 

1838. 

Bayfield. 

20 

23 

+ 0 

07 

20 

30 

Carleton  Point. 

49 

15 

294 

16 

1828. 

Bayfield. 

22 

00 

+ 1 

03 

23 

03 

Mount  Louis  River. 

41 

29 

294 

22 

June  1841. 

Barnett. 

12 

27 

— 0 

05 

12 

22 

At  seaf. 

48 

01 

294 

25 

1838. 

Bayfield. 

21 

21 

+ 0 

08 

21 

29 

Paspebiac. 

47 

06 

294 

55 

1837. 

Bayfield. 

19 

46 

+ 0 

15 

20 

01 

Vin  Island,  Mirainichi. 

41 

28 

294 

57 

June  1841. 

Barnett. 

13 

05 

-0 

05 

13 

00 

At  seaf. 

47 

49 

295 

08 

1838. 

Bayfield. 

21 

30 

+ 0 

09 

21 

39 

Caraquette  Island. 

46 

43 

295 

12 

1839. 

Bayfield. 

19 

50 

+ 0 

03 

19 

53 

Richibucto  River. 

48 

12 

295 

13 

1837. 

Bayfield. 

22 

00 

+ 0 

15 

22 

15 

Point  Macquereaw. 

47 

45 

295 

17 

1838. 

Bayfield. 

21 

43 

+ 0 

09 

21 

52 

Sliinfrigan  Harbour. 

48 

01 

295 

30 

1838. 

Bayfield. 

20 

35 

+ 0 

09 

20 

44 

Miscow  Harbour. 

48 

50 

295 

30 

1846. 

Bayfield. 

22 

49 

— 0 

37 

22 

12 

Gaspe  Basin. 

41 

28 

295 

34 

June  1841. 

Barnett. 

13 

08 

— 0 

05 

13 

03 

At  sea'!'. 

49 

48 

295 

36 

1830. 

Bayfield. 

24 

22 

+ 0 

52 

25 

14 

Cape  Henry,  Anticosti. 

46 

15 

295 

37 

1839. 

Bayfield. 

19 

59 

+ 0 

03 

20 

02 

Shediac  Island. 

46 

48 

295 

57 

1845. 

Bayfield. 

21 

10 

— 0 

32 

20 

38 

Cascurnpique. 

46 

10 

296 

10 

1840. 

Bayfield. 

20 

00 

— 0 

03 

19 

37 

Cape  Tormentine. 

46 

24 

296 

12 

1841. 

Bayfield. 

20 

12 

-0 

09 

20 

03 

Bedeque  Harbour. 

46 

15 

296 

17 

1840. 

Bayfield. 

20 

18 

-0 

03 

20 

15 

Carleton  Head. 

46 

34 

296 

17 

1845. 

Bayfield. 

21 

00 

— 0 

33 

20 

27 

Richmonfl  Bay. 

45 

53 

296 

19 

1840. 

Bayfield. 

19 

40 

-0 

03 

19 

37 

Pugwash  Harbour. 

45 

49 

296 

34 

1840. 

Bayfield. 

19 

50 

— 0 

03 

19 

47 

Wallace  Harbour. 

46 

30 

296 

40 

1845. 

Bayfield. 

21 

41 

-0 

33 

21 

08 

Cape  Turner. 

46 

14 

296 

52 

1842. 

Bayfield. 

21 

03 

— 0 

15 

20 

48 

Charlotte  Town. 

45 

41 

297 

20 

1841. 

Bavfield. 

20 

19 

— 0 

09 

20 

10 

Picton  Harbour. 

46 

11 

297 

27 

1843. 

Bayfield. 

21 

58 

— 0 

21 

21 

37 

George  Town. 

45 

38 

297 

33 

1842. 

Bayfield. 

20 

15 

— 0 

15 

20 

00 

Merigomish  Harbour. 

41 

48 

297 

S8 

June  1841. 

Barnett. 

15 

54 

-0 

06 

15 

48 

At  seaf. 

49 

34 

298 

07 

1842. 

Lefroy. 

27 

23 

-0 

17 

27 

06 

At  seaf. 

47 

14 

298 

10 

1833. 

Bavfield. 

22 

36 

+ 0 

45 

23 

21 

Amherst  Harbour. 

49 

08 

298 

18 

1830. 

Bavfield. 

25 

19 

+ 1 

07 

26 

26 

East  Point  (Anticosti). 

45 

30 

299 

04 

June  1848. 

Kelly. 

21 

05 

— 0 

59 

20 

06 

Isle  Madame. 

45 

35 

299 

05 

Sept.  1 848. 

Kelly. 

22 

30 

-0 

59 

21 

31 

Isle  Madame. 

46 

17 

299 

37 

Aug.  1848. 

Kelly. 

23 

41 

— 0 

59 

22 

42 

St.  Ann’s  Harbour,  Cape  Breton. 

48 

05 

299 

40 

1842. 

Lefroy. 

26 

47 

-0 

18 

26 

29 

At  seaf. 

49 

11 

299 

47 

1842. 

Lefroy. 

28 

16 

— 0 

18 

27 

58 

At  seaf. 

47 

18 

300 

15 

1842. 

Lefroy. 

25 

17 

— 0 

18 

24 

59 

At  seaf. 

47 

53 

300 

35 

1835. 

Bayfield. 

25 

00 

+ 0 

32 

25 

32 

Cod  Roy  Island. 

41 

34 

304 

23 

June  1841. 

Barnett. 

18 

28 

— 0 

09 

18 

19 

At  seaf. 

46 

13 

304 

53 

1842. 

Lefroy. 

26 

32 

— 0 

23 

26 

09 

At  seaf. 

45 

52 

306 

49 

1842. 

Lefroy. 

28 

04 

— 0 

23 

27 

41 

At  seaf. 

41 

50 

307 

14 

Oct.  1839. 

Berard. 

19 

00 

+ 0 

02 

19 

02 

At  sea. 

47 

34 

307 

19 

1844. 

Bayfield. 

29 

36 

— 0 

43 

28 

53 

St.  John’s,  Newfoundland. 

42 

54 

307 

37 

June  1841. 

Barnett. 

22 

22 

-0 

12 

22 

10 

At  seaf. 

45 

12 

309 

48 

1842. 

Lefroy. 

27 

00 

-0 

22 

26 

38 

At  seaf. 

43 

19 

313 

35 

June  1841. 

Barnett. 

24 

57 

-0 

12 

24 

45 

At  sea  f . 

43 

34 

314 

42 

Aug.  1842. 

Lefroy. 

26 

49 

— 0 

23 

26 

26 

At  seaf. 

43 

06 

315 

00 

Aug.  1842. 

Lefroy. 

26 

15 

-0 

24 

25 

51 

At  seaf. 

43 

00 

316 

10 

June  1841. 

Barnett. 

25 

43 

-0 

14 

25 

29 

At  seaf. 

43 

30 

317 

51 

Oct.  1839. 

Berard. 

23 

55 

+ 0 

03 

23 

58 

At  seaf. 

44 

33 

318 

47 

Aug.  1 842. 

Lefroy. 

27 

37 

— 0 

24 

27 

13 

At  seaf. 

43 

37 

319 

18 

Aug.  1842. 

Lefroy. 

28 

17 

— 0 

24 

27 

53 

At  seaf. 

42 

20 

320 

18 

Aug.  1842. 

Lefroy. 

27 

07 

-0 

22 

26 

45 

At  seaf. 

42 

59 

321 

28 

Aug.  1842. 

Lefroy. 

27 

20 

-0 

22 

26 

58 

At  seaf. 

43 

26 

322 

00 

June  1841. 

Barnett. 

28 

51 

-0 

12 

28 

39 

At  seaf. 

212 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat.  1 

Long. 

Date.  1 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  50° 

and  40° 

(continued). 

44 

14 

323 

22 

Aug.  1842. 

Lefroy. 

O 

28 

32 

— 0 

/ 

22 

0 

28 

10 

At  seaf. 

40 

32 

323 

26 

Oct.  1837. 

Vaillant. 

24 

52 

+ 0 

20 

25 

12 

At  sea. 

46 

09 

323 

37 

Aug.  1842. 

Lefroy. 

30 

38 

-0 

25 

30 

13 

At  sea)*. 

40 

30 

323 

56 

Oct.  1837. 

Vaillant. 

25 

35 

+ 0 

20 

25 

55 

At  sea. 

43 

34 

324 

30 

June  1841. 

Barnett. 

28 

22 

-0 

12 

28 

10 

At  seaf. 

43 

50 

324 

30 

June  1841. 

Barnett. 

27 

12 

— 0 

12 

27 

00 

At  seaf. 

48 

11 

324 

30 

Aug.  1842. 

Lefroy. 

31 

23 

-0 

25 

30 

58 

At  seaf. 

42 

03 

325 

11 

Oct.  1837. 

Vaillant. 

24 

25 

+ 0 

20 

24 

45 

At  sea. 

40 

37 

325 

13 

Oct.  1837. 

Vaillant. 

26 

42 

+ 0 

20 

27 

02 

At  sea. 

47 

06 

325 

40 

Aug.  1842. 

Lefroy. 

32 

24 

-0 

25 

31 

59 

At  seaf. 

40 

55 

326 

08 

Aug.  1830. 

Ernian. 

24 

48 

+ 1 

16 

26 

04 

At  sea. 

46 

41 

326 

36 

Aug.  1842. 

Lefroy. 

30 

47 

— 0 

22 

30 

25 

At  seaf. 

41 

39 

327 

19 

Aug.  1830. 

Erman. 

25 

16 

+ 1 

12 

26 

28 

At  sea. 

43 

26 

329 

27 

Aug.  1830. 

Ernian. 

26' 

35 

+ 1 

08 

27 

43 

At  sea. 

42 

39 

329 

55 

Oct.  1837. 

Vaillant. 

23 

26 

+ 0 

15 

23 

41 

At  sea. 

47 

21 

330 

56 

Aug.  1842. 

Lefroy. 

30 

49 

— 0 

18 

30 

31 

At  seaf. 

44 

35 

330 

57 

Aug.  1830. 

Erman- 

27 

36 

+ 1 

10 

28 

46 

At  sea. 

41 

37 

331 

37 

1839. 

Du  Petit- Thouars. 

22 

07 

+ 0 

04 

22 

11 

At  sea. 

45 

41 

332 

57 

Atig.  1830. 

Erman. 

28 

08 

+ 1 

02 

29 

10 

At  sea. 

43 

18 

333 

04 

Oct.  1837. 

Vaillant. 

24 

22 

+ 0 

13 

24 

35 

At  sea. 

46 

53 

334 

07 

June  1841. 

Barnett. 

29 

40 

-0 

08 

29 

32 

At  seaf. 

46 

20 

335 

05 

Aug.  1830. 

Erman. 

28 

18 

+ 0 

57 

29 

15 

At  sea. 

47 

20 

335 

09 

Aug.  1 842. 

Lefroy. 

31 

13 

— 0 

16 

30 

57 

At  seaf. 

46 

49 

336 

05 

.Tune  1841. 

Barnett. 

30 

04 

-0 

08 

29 

56 

At  seaf. 

44 

03 

336 

25 

Oct.  1837. 

Vaillant. 

24 

20 

+ 0 

14 

24 

34 

At  sea. 

45 

45 

336 

26 

Oct.  1839. 

Berard. 

25 

30 

-fO 

02 

25 

32 

At  sea. 

47 

33 

336 

56 

Aug.  1842. 

Lefroy. 

31 

17 

-0 

16 

31 

01 

At  seaf. 

40 

35 

337 

15 

1836. 

FitzRoy. 

25 

00 

+ 0 

14 

25 

14 

At  sea. 

46 

43 

338 

23 

Oct.  1839. 

Berard. 

27 

00 

+ 0 

01 

27 

01 

At  sea. 

46 

53 

338 

25 

June  1841. 

Barnett. 

30 

51 

— 0 

06 

30 

45 

At  seaf. 

41 

28 

338 

29 

1836. 

FitzRoy. 

25 

38 

+ 0 

14 

25 

52 

At  sea. 

47 

03 

339 

07 

Aug.  1830. 

Erman. 

27 

51 

-f  0 

45 

28 

36 

At  sea. 

47 

37 

339 

46 

June  1841. 

Barnett. 

30 

30 

— 0 

06 

30 

24 

At  seaf. 

42 

06 

339 

54 

1836. 

FitzRov. 

26 

00 

+ 0 

12 

26 

12 

At  sea. 

43 

14 

340 

17 

June  1839. 

Du  Petit-Thouars. 

22 

52 

+ 0 

02 

22 

54 

At  sea. 

48 

02 

340 

55 

Aug.  1842. 

Lefroy. 

30 

51 

-0 

12 

30 

39 

At  seaf. 

47 

55 

342 

25 

June  1841. 

Barnett. 

28 

23 

-0 

05 

28 

18 

At  seaf. 

48 

11 

343 

18 

June  1841. 

Barnett. 

29 

26 

-0 

05 

29 

21 

At  seaf. 

49 

16 

343 

51 

Sept.  1846. 

Moore. 

32 

01 

— 0 

20 

31 

41 

At  seaf. 

44 

05 

344 

05 

June  1839. 

Du  Petit-Thouars. 

23 

09 

+ 0 

02 

23 

11 

At  sea. 

48 

18 

344 

23 

Aug.  1842. 

Lefroy. 

29 

29 

-0 

08 

29 

21 

At  seat- 

47 

56 

345 

03 

Aug.  1830. 

Erman. 

26 

19 

+ 0 

29 

26 

48 

At  sea. 

48 

34 

346 

00 

June  1841. 

Barnett. 

28 

37 

— 0 

05 

28 

32 

At  seat- 

40 

15 

346 

10 

1836. 

FitzRoy. 

24 

45 

+ 0 

10 

24 

55 

At  sea. 

41 

00 

346 

30 

1836. 

FitzRoy. 

24 

49 

+ 0 

10 

24 

59 

At  sea. 

42 

31 

347 

20 

1836. 

FitzRoy. 

24 

18 

+ 0 

10 

24 

28 

At  sea. 

42  37 

347 

30 

1836. 

FitzRoy. 

23 

34 

+ 0 

10 

23 

44 

At  sea. 

43 

20 

348 

00 

1836. 

FitzRoy. 

23 

50 

+ 0 

10 

24 

00 

At  sea. 

48 

42 

348 

04 

June  1841. 

Barnett. 

27  22 

-0 

05 

27 

17 

At  seaf. 

48 

27 

348 

32 

Aug.  1830. 

Erman. 

26 

07 

+ 0 

23 

26 

30 

At  sea. 

48 

48 

349 

28 

Aug.  1842. 

Lefroy. 

27 

44 

-0 

03 

27 

41 

At  seaf. 

49 

25 

350 

15 

Sept.  1846. 

Moore. 

27 

46 

0 

00 

27 

46 

At  seaf. 

48 

57 

350 

28 

Aug.  1 830. 

Erman. 

25 

54 

+ 0 

10 

26 

04 

At  sea. 

46 

18 

351 

54 

June  1839. 

Du  Petit-Thouars. 

24 

14 

0 

00 

24 

14 

At  sea. 

46 

38 

351 

54 

Dec.  1842. 

Jehenne. 

27 

10 

0 

00 

27 

10 

At  sea. 

49 

11 

352 

22 

Aug.  1842. 

Lefroy. 

26 

16 

+0 

05 

26 

21 

At  seaf. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


213 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  50' 

^ and  40' 

(continued). 

O 

47 

20 

35.3 

/ 

14 

Aug.  ]830.!Erman. 

O 

25 

10 

O 

0 

00 

o 

25 

10 

At  sea. 

47 

44 

354 

16 

Aug.  1830.Erman. 

24 

35 

0 

00 

24 

35 

At  sea. 

48 

09 

355 

02 

June  1839.IDu  Petit-Thouars. 

24 

03 

0 

00 

04 

03 

At  sea. 

46 

59 

355 

13 

Aug.  1830jErman. 

24 

02 

0 

00 

24 

02 

At  sea. 

48 

23 

355 

31 

Nov.  1837. 

Darondean. 

24 

58 

— 0 

10 

24 

48 

Brest. 

49 

58 

356 

27 

Aug.  1842. 

Lefroy. 

25 

18 

0 

00 

25 

18 

At  seaf. 

40 

22 

1 

56 

June  1838. 

Berard. 

20 

01 

0 

00 

20 

01 

At  sea. 

48 

50 

2 

22 

Feb.  1838. 

Darondean. 

21 

38 

0 

00 

21 

38 

Paris  Observatory. 

40 

13 

2 

26 

Aug.  1842. 

Berard. 

19 

45 

0 

00 

19 

45 

At  sea. 

40 

24 

2 

27 

June  1838. 

Berard. 

21 

29 

0 

00 

21 

29 

At  sea. 

40 

48 

2 

30 

Aug.  1842. 

Berard. 

19 

00 

0 

00 

19 

00 

At  sea. 

41 

11 

2 

39 

Aug.  1842. 

Berard. 

19 

30 

0 

00 

19 

30 

At  sea. 

41 

26 

3 

52 

Aug.  1842. 

Berard. 

19 

30 

0 

00 

19 

30 

At  sea. 

41 

32 

4 

18 

Aug.  1842. 

Berard. 

19 

00 

0 

00 

19 

00 

At  sea. 

42 

04 

4 

48 

Aug.  1842. 

Berard. 

18 

30 

0 

00 

18 

30 

At  sea. 

43 

05 

5 

55 

Jan.  1836. 

Darondean. 

19 

16 

0 

00 

19 

16 

Toulon. 

46 

12 

6 

09 

Jan.  1843. 

Plantamour. 

18 

57 

+ 0 

15 

19 

12 

Geneva. 

Between  the  latitudes  of  40'^  and  30 

0 

32 

41 

280 

07 

May  1841. 

Barnett. 

- 2 

24 

-0 

05 

2 

29lcharleston. 

30 

54 

280 

15 

May  1841. 

Barnett. 

— 3 

07 

— 0 

05 

— 3 

12 

At  seaf. 

31 

54 

280 

29 

May  1841. 

Barnett. 

— 2 

45 

-0 

05 

— 2 

50 

At  seaf. 

38 

56 

283 

25 

June  1 845. 

U.S.  Coast  Survey. 

+ 2 

14 

— 0 

08 

+ 2 

06 

-'Annapolis. 

33 

55 

283 

57 

May  1841. 

Barnett. 

— 1 

25 

— 0 

05 

— 1 

30 

At  seaf. 

39 

22 

284 

30 

June  1846. 

U.S.  Coast  Survey. 

+ 3 

18 

— 0 

08 

+ 3 

10 

Bombay  Hook. 

39 

25 

284 

40 

June  1846. 

U.S.  Coast  Survey. 

2 

15 

-0 

08 

2 

07 

39 

58 

284 

50 

May  1846. 

U.S.  Coast  Survey. 

3 

51 

-0 

08 

3 

43 

Girard  College. 

39 

10 

284 

52 

June  1846. 

U.S.  Coast  Survey. 

2 

59 

-0 

08 

2 

51 

Egg  Island. 

38 

47 

284 

54 

May  1841. 

Barnett. 

4 

42 

— 0 

05 

4 

37 

Cape  Henlopen. 

39 

15 

284 

59 

June ] 846. 

U.S.  Coast  Survey. 

3 

06 

-0 

05 

3 

01 

Port  Norris. 

35 

08 

285 

28 

May  1841. 

Barnett. 

1 

57 

-0 

05 

1 

52 

At  seaf. 

38 

00 

285 

35 

May  1841. 

Barnett. 

3 

51 

-0 

02 

3 

49 

At  seaf. 

39 

31 

285 

41 

Nov.  1846. 

U.S.  Coast  Survey. 

4 

24 

— 0 

05 

4 

19 

Tuche  Island. 

38 

45 

289 

09 

May  1841. 

Barnett. 

6 

44 

-0 

07 

6 

37 

At  seaf. 

39 

18 

290 

20 

May  1841. 

Barnett. 

6 

58 

-0 

07 

6 

51 

At  seaf. 

39 

37 

290 

30 

May  1841. 

Barnett. 

7 

25 

-0 

07 

7 

18 

At  seaf. 

39 

52 

291 

20 

May  1841. 

Barnett. 

7 

42 

-0 

07 

7 

35 

At  seaf. 

32 

23 

295 

09 

Aug.  1846. 

Barnett. 

6 

53 

-0 

39 

6 

14 

Bermuda. 

32 

23 

295 

16 

May  1837. 

Milne. 

6 

40 

+ 0 

15 

6 

55 

Bermuda. 

32 

18 

300 

42 

Nov.  1842. 

Jehennc. 

8 

46 

— 0 

18 

8 

28 

At  sea. 

33 

53 

318 

07 

Aug.  1830. 

Erman. 

17 

00 

+ 1 

26 

18 

26 

At  sea. 

34 

44 

318 

13 

Aug.  1830. 

Erman. 

17 

03 

+1 

26 

18 

29 

At  sea. 

33 

39 

318 

32 

Aug.  1830. 

Ei'man. 

17 

00 

+ 1 

26 

18 

26 

At  sea. 

31 

36 

318 

58 

June  1839. 

Du  Petit-Thouars. 

16 

00 

+ 0 

04 

16 

04 

At  sea. 

32 

53 

318 

58 

Aug.  1830. 

Erman. 

16 

28 

+ 1 

26 

17 

54 

At  sea. 

31 

56 

319 

20 

June  1839. 

Du  Petit-Thouars. 

15 

52 

+ 0 

04 

15 

56 

At  sea. 

35 

59 

319 

32 

Aug.  1830. 

Erman. 

18 

02 

+ 1 

26 

19 

28 

At  sea. 

31 

48 

319 

36 

Aug.  1830. 

Erman. 

15 

40 

+ 1 

26 

17 

06 

At  sea. 

30 

32 

319 

45 

Aug.  1 830. 

Erman. 

15 

03 

+ 1 

26 

16 

29 

At  sea. 

34 

04 

320 

12 

June  1839. 

Du  Petit-Thouars. 

17 

22 

+ 0 

04 

17 

26 

At  sea. 

30 

48 

320 

16 

May  1846. 

Sulivan. 

17 

47 

-0 

58 

16 

49 

At  seaf. 

32 

10 

321 

05 

May  1846. 

Sulivan. 

18 

15 

— 0 

58 

17 

17 

At  seaf. 

37 

28 

321 

25 

Aug.  1830. 

Erman. 

19 

43 

+ 1 

26 

21 

09 

At  sea. 

30 

02 

321 

27 

June  1 839. 

Du  Petit-Thouars. 

18 

30  +0 

04 

18 

34 

At  sea. 

37 

05 

321 

35 

Nov.  1842. 

Jehenne. 

21 

02 

-0 

22 

20 

40 

At  sea. 

33 

46 

322 

10 

May  1846. 

Sulivan. 

19 

15 

-0 

55 

18 

20 

At  seaf. 

35 

17 

322 

14 

Oct.  1837. 

Vaillant. 

18 

37 

+0 

20 

18 

57 

At  sea. 

2 p 


MDCCCXLIX. 


214 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  40 

^ and  30°  (continued). 

33  17 

322  37 

July  1846. 

Berard. 

o / 

19  13 

O / 

-0  57 

o / 

18  16 

At  sea. 

36  18 

322  46 

Oct.  1837. 

Vaillant. 

17  33 

+ 0 20 

17  53 

At  sea. 

38  43 

323  02 

Aug.  1830. 

Erman. 

21  43 

+ 1 20 

23  03 

At  sea. 

37  48 

323  07 

June  1839. 

Du  Petit-Thouars. 

19  57 

+ 0 04 

20  01 

At  sea. 

32  11 

323  13 

July  1846. 

Berard. 

18  30 

— 0 57 

17  33 

At  sea. 

33  54 

323  14 

Oct.  1837. 

Vaillant. 

18  02 

-hO  20 

18  22 

At  sea. 

32  46 

323  41 

July  1846. 

Berard. 

18  29 

— 0 55 

17  34 

At  sea. 

31  04 

324  03 

1836. 

FitzRoy. 

18  28 

+ 0 28 

18  56 

At  sea. 

39  15 

324  36 

Aug.  1 830. 

Erman. 

23  06 

+ 1 16 

24  22 

At  sea. 

37  09 

324  36 

Mav  1846. 

Sulivan. 

23  37 

-0  52 

22  45 

At  seaf. 

30  01 

324  39 

Oct.  1837. 

Vaillant. 

18  38 

+ 0 20 

18  58 

At  sea. 

32  03 

324  55 

1836. 

FitzRoy. 

18  22 

+ 0 28 

18  50 

At  sea. 

34  35 

325  11 

July  1846. 

Berard. 

18  34 

-0  52 

17  40 

At  sea. 

37  40 

325  15 

Mav  1846. 

Sulivan. 

23'  50 

— 0 50 

23  00 

At  seaf. 

31  01 

325  41 

Oct.  1837. 

Vaillant. 

18  02 

+ 0 19 

18  21 

At  sea. 

39  32 

325  54 

June  1839. 

Du  Petit-Thouars. 

20  55 

+ 0 04 

20  59 

At  sea. 

38  10 

325  55 

Mav  1846. 

Sulivan. 

23  21 

-0  50 

22  31 

At  seaf. 

35  17 

326  58 

July  1846. 

Berard. 

19  49 

-0  52 

18  57 

At  sea. 

36  38 

327  48 

July  1846. 

Berard. 

20  59 

— 0 52 

20  07 

At  sea. 

35  38 

328  28 

1836. 

FitzRoy. 

21  34 

+ 0 26 

22  00 

At  sea. 

39  24 

328  48 

1843-1844 

Vidal. 

27  30 

— 0 25 

27  05 

Flores. 

39  41 

328  53 

1842. 

Vidal. 

27  30 

— 0 18 

27  12 

Corvo. 

36  40 

330  52 

July  1846. 

Berard. 

20  42 

— 0 52 

19  50 

At  sea. 

37  15 

331  06 

1836. 

FitzRoy. 

22  09 

-fO  26 

22  35 

At  sea. 

39  05 

331  56 

1843-1844 

Vidal. 

26  46 

— 0 25 

26  21 

Graciosa. 

37  49 

332  00 

1836. 

FitzRoy. 

24  00 

4-0  26 

24  26 

At  sea. 

38  39 

332  47 

1836. 

FitzRoy. 

24  19 

+ 0 26 

24  45 

Terceira. 

38  45 

332  52 

July  1836. 

FitzRoy. 

24  21 

+ 0 26 

24  47 

At  sea. 

37  44 

334  17 

May  1831. 

Austin. 

24  31 

+ 0 54 

25  25 

St.  Michaels. 

37  48 

334  20 

1836. 

FitzRoy. 

24  15 

+ 0 22 

24  37 

St.  Michaels. 

37  46 

334  20 

1843-1844 

Vidal. 

25  45 

-0  22 

25  23 

St.  Michaels. 

36  57 

334  55 

1843-1844 

Vidal. 

25  17 

— 0 22 

24  55 

Santa  Maria. 

36  19 

339  41 

Aug.  1 846. 

Berard. 

20  51 

— 0 36 

20  15 

At  sea. 

37  05 

341  35 

Nov.  1842. 

Jehenne. 

21  02 

— 0 10 

20  52 

At  sea. 

33  00 

343  50 

1832. 

FitzRoy. 

23  00 

4-0  34 

23  34 

At  sea. 

37  20 

344  30 

1836. 

FitzRoy. 

23  54 

d-O  14 

24  08 

At  sea. 

38  41 

345  00 

1836. 

FitzRoy. 

23  35 

-fO  14 

23  49 

At  sea. 

30  02 

346  18 

Feb.  1836. 

Vaillant. 

22  24 

+ 0 22 

22  46 

At  sea. 

30  41 

346  36 

Sept.  1842. 

Berard. 

22  00 

-0  11 

21  49 

At  sea. 

31  16 

347  32 

Sept.  1842. 

Berard. 

23  00 

-0  11 

22  49 

At  sea. 

33  16 

348  09 

June  1838. 

Berard. 

20  01 

-fO  06 

20  07 

At  sea. 

32  19 

348  49 

Sept.  1842. 

Berard. 

22  45 

— 0 11 

22  34 

At  sea. 

33  34 

349  06 

Feb.  1836. 

Vaillant. 

24  31 

+ 0 23 

24  54 

At  sea. 

33  00 

350  05 

Sept.  1842. 

Berard. 

22  00 

-0  08 

21  52 

At  sea. 

34  10 

351  20 

Sept.  1842. 

Berard. 

22  00 

— 0 08 

21  52 

At  sea. 

31  57 

351  51 

June  1838. 

Berard. 

20  05 

4-0  05 

20  10 

At  sea. 

35  59 

352  14 

Feb.  1836. 

Vaillant. 

22  20 

-pO  10 

22  30 

At  sea. 

35  25 

352  16 

Aug.  1846. 

Berard. 

21  05 

— 0 15 

20  50 

At  sea. 

35  25 

353  11 

June  1838. 

Berard. 

22  13 

+ 0 03 

22  16 

At  sea. 

36  11 

353  34 

Aug.  1846. 

Berard. 

20  26 

-0  12 

20  14 

At  sea. 

35  29 

353  47 

Aug.  1846. 

Berard. 

20  35 

-0  12 

20  23 

At  sea. 

36  26 

356  03 

Aug.  1846. 

Berard. 

19  15 

0 00 

19  15 

At  sea. 

35  48 

357  00 

1842. 

Berard. 

18  30 

-fO  03 

18  33 

At  sea. 

36  20 

358  52 

Aug.  1846. 

Berard. 

18  49 

+ 0 10 

18  59 

At  sea. 

36  46 

358  53 

June  1838. 

Berard. 

19  47 

-0  04 

19  43 

At  sea. 

36  28 

359  19 

Aug.  1846. 

Berard. 

19  16 

+ 0 18 

19  34 

At  sea. 

36  10 

359  40 

Aug.  1846. 

Berard. 

19  18 

4-0  18 

19  36 

At  sea. 

38  58 

1 00 

Aug.  1846. 

Berard. 

19  48 

+ 0 18 

20  06 

A.t  sea. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


215 


Table  XIL  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observec 

Decbna- 

tion. 

Correc- 
tion for 
Epoch. 

Correcte 

Declina- 

tion. 

1 

Remarks. 

Between  the  latitudes  of  30°  and  20°. 

37  33 

0 / 

1 15 

1 

Aug.  1842.'Berard. 

0 

17  3: 

' 0 

1 +0  07 

0 

17  4^ 

1 At  sea. 

36  47 

3 05 

Oct.  1842.jAime. 

18  35 

-po  08 

18  4; 

1 Algiers  Magnetic  Observatory. 

28  22 

279  35 

May  1841. ’Barnett. 

- 4 5: 

-0  05 

— 5 05 

1 At  seaf. 

29  17 

280  24 

May  1841 

.jBarnett. 

— 4 44 

— 0 05 

— 4 45 

t At  seaf. 

25  05 

282  39 

May  1838.  Milne. 

— 3 0/ 

' -fO  03 

— 3 0^ 

: Nassau. 

20  00 

283  57 

July  1837 

, Milne. 

— 3 3C 

» -pO  04 

— 3 05 

St.  Jago,  Cuba. 

21  33 

284  15 

Milne. 

— 4 02 

-PO  03 

- 3 5c 

1 San  Domingo. 

27  55 

285  24 

Nov.  1842 

. Jehenne. 

— 2 07 

-0  09 

- 2 16 

At  sea. 

20  22 

285  26 

1831 

. Austin. 

- 3 17 

+ 0 12 

- 3 05 

Barracon,  Cuba. 

22  07 

285  36 

1831 

Austin. 

— 4 27 

-pO  12 

— 4 15 

Crooked  Island. 

22  47 

285  39 

July  1837 

Milne. 

— 2 34 

-pO  05 

- 2 2S 

Crooked  Island. 

20  14 

285  48 

1831 

Austin. 

— 2 27 

-pO  12 

- 2 15 

Cape  Maize. 

21  26 

288  53 

Nov.  1845 

Barnett. 

— 1 48 

— 0 12 

— 2 00 

Turks  Island,  Bahamas. 

28  15 

315  50 

June  1839 

Du  Petit- Thouars. 

13  32 

-pO  04 

13  36 

At  sea. 

29  11 

316  36 

June 18?9 

Du  Petit-Thouars. 

14  16 

-pO  02 

14  18 

At  sea. 

27  51 

316  53 

June  1839 

Du  Petit-Thouars. 

13  25 

-pO  02 

13  27 

At  sea. 

26  57 

318  08 

June  1839 

Du  Petit-Thouars. 

12  37 

-pO  02 

12  39 

At  sea. 

25  13 

319  09 

June  1839 

Du  Petit-Thouars. 

12  30 

-pO  02 

12  32 

At  sea. 

26  32 

319  46 

May  1846. 

Sulivan. 

13  17 

-0  42 

12  35 

At  seaf. 

29  27 

319  50 

May  1846. 

Sulivan. 

14  24 

— 0 42 

13  42 

At  seaf. 

24  00 

320  08 

June  1839. 

Du  Petit-Thouars. 

11  30 

+ 0 03 

11  33 

At  sea. 

21  34 

320  18 

May  1846. 

Sulivan. 

12  29 

-0  42 

11  47 

At  seaf. 

20  19 

320  45 

May  1846. 

Sulivan. 

11  23 

— 0 42 

10  41 

At  seaf. 

22  34 

320  56 

June  1839. 

Du  Petit-Thouars. 

11  20 

-pO  03 

11  23 

At  sea. 

28  12 

321  08 

Aug.  1830. 

Erman. 

14  33 

-pi  16 

15  49 

At  sea. 

26  23 

.321  57 

Aug.  1830. 

Erman. 

13  07 

-pi  03 

14  10 

At  sea- 

23  41 

322  14 

1830. 

Erman. 

11  50 

-pO  50 

12  40 

At  sea. 

29  15 

323  40 

1836. 

FitzRoy. 

17  10 

-po  27 

17  37 

At  sea. 

22  48 

323  55 

July  1838. 

Berard. 

9 40 

-pO  08 

9 48 

At  sea. 

28  07 

324  00 

1836. 

FitzRoy. 

17  06 

-PO  21 

17  27 

At  sea. 

29  52 

324  34 

July  1846. 

Berard. 

17  55 

-0  39 

17  16 

At  sea. 

21  42 

324  35 

1830. 

Erman. 

11  58 

+ 0 47 

12  45 

At  sea. 

28  13 

324  41 

July  1846. 

Berard. 

17  30 

-0  39 

16  51 

At  sea. 

27  17 

325  13 

July  1846. 

Berard. 

17  57 

-0  39 

17  18 

At  sea. 

29  17 

325  32 

Oct.  1837. 

Vaillant. 

17  26 

-po  18 

17  44 

At  sea. 

25  00 

325  41 

1836. 

FitzRoy. 

16  05 

-po  21 

16  26 

At  sea. 

26  52 

325  52 

July  1846. 

Berard. 

18  30 

-0  39 

17  51 

At  sea. 

23  41 

326  11 

1836. 

FitzRoy. 

15  20 

-po  21 

15  41 

At  sea. 

25  44 

326  34 

July  1846. 

Berard. 

17  26 

-0  39 

16  47 

At  sea. 

25  57 

327  12 

Oct.  1837. 

Vaillant. 

16  37 

-po  15 

16  52 

At  sea. 

23  20 

327  23 

July  1846. 

Berard. 

15  19 

— 0 33 

14  46 

At  sea. 

23  02 

327  30 

July  1838. 

Berard. 

10  30 

-po  08 

10  38 

At  sea. 

21  27 

328  42 

July  1846. 

Berard. 

16  41 

-po  33 

16  08 

At  sea. 

22  30 

329  04 

Oct.  1837. 

Vaillant. 

14  54 

-pO  12 

15  06. 

At  sea. 

20  32 

330  00 

Oct.  1837. 

Vaillant. 

14  22 

-po  12 

14  34. 

At  sea. 

25  05 

330  33  . 

July  1838. 

Berard. 

16  44 

-po  15 

16  59. 

At  sea. 

26  12 

333  21  . 

July  1838. 

Berard. 

17  19 

-po  15 

17  34. 

At  sea. 

20  24 

337  11  J 

5ept.  1842. 

Berard. 

19  30 

— 0 15 

19  15. 

At  sea. 

21  24 

338  04  1 

Oec.  1846. 

Stanley. 

18  14 

-0  38 

17  36. 

At  seaf. 

22  24 

338  29  5 

iept.  1842.  ’ 

Berard. 

20  00 

— 0 15 

19  45. 

At  sea. 

20  18 

338  32 

1832.] 

^itzRoy. 

18  20 

-po  45 

19  05. 

it  sea. 

20  42 

338  39 

1832.1 

^itzRoy. 

18  24 

-pO  45 

19  09i 

it  sea. 

23  22 

339  08  I 

Oec.  1846.5 

Stanley. 

19  41 

-0  41 

19  OOi 

it  seaf. 

21  43 

339  20 

1832.1 

^itzRoy. 

18  30 

-pO  45 

19  15. 

it  sea. 

21  10 

339  35 

Jan.  1837.1 

Ou  Petit-Thouars. 

18  42 

+ 0 18 

19  OOP 

it  sea. 

22  22 

340  04  p 

vlov.  1839. 1 

loss. 

19  25 

0 00 

19  25  i 

it  seaf. 

2 F 2 


216 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Dbserved 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected  | 
Declina-  I 
tion.  ] 

Remarks. 

Between  the  latitudes  of  30° 

and  20° 

(continued). 

23  09 

340  13 

1832. 

FitzRoy. 

18  47 

-fO  44 

O / 

19  31 

At  sea. 

22  01 

340  16 

Feb.  1836. 

Vaillant. 

20  08 

-fO  24 

20  32 

At  sea. 

21  50 

340  28 

Jan.  1837- 

[)u  Petit-Thouars. 

20  03 

-pO  16 

20  19 

At  sea. 

23  38 

340  43 

Nov.  1839. 

Eloss. 

19  30 

0 00 

19  30 

At  seat- 

23  50 

340  51 

Nov.  1839. 

Uoss. 

19  12 

0 00 

19  12 

At  seat- 

26  17 

340  59 

Sept.  1842. 

Serard. 

21  00 

-0  15 

20  45 

At  sea. 

23  31 

341  10 

Tan.  1837. 

Du  Petit-Thouars. 

19  55 

-pO  16 

20  11 

At  sea- 

24  31 

34i  17 

Nov.  1839. 

Uoss. 

20  15 

0 00 

20  15 

At  seat- 

24  40 

341  18 

1832. 

FitzRoy. 

19  53 

-PO  41 

20  34 

At  sea. 

23  37 

341  31 

Feb.  1836. 

Vaillant. 

21  02 

-PO  21 

21  23 

At  sea. 

25  33 

341  55 

Nov.  1839. 

Ross. 

21  33 

0 00 

21  33 

At  seat- 

25  26 

341  58 

1832. 

FitzRoy. 

19  59 

+ 0 41 

20  40 

At  sea. 

24  58 

342  56 

Feb.  1836. 

Vaillant. 

20  35 

-pO  21 

20  56 

At  sea. 

27  59 

343  01 

Sept.  1842. 

Berard. 

21  00 

-0  15 

20  45 

At  sea. 

26  59 

343  12 

1832. 

FitzRoy. 

20  04 

-pO  41 

20  45 

At  sea. 

28  12 

343  40 

1832. 

FitzRoy. 

20  20 

-pO  41 

21  01 

At  sea. 

29  31 

343  40 

1832. 

FitzRoy. 

20  44 

-pO  41 

21  25 

At  sea. 

28  26 

343  44 

Nov.  1839. 

Ross. 

20  31 

0 00 

20  31 

At  seat- 

28  28 

343  45 

1837. 

Vidal. 

22  40 

+ 0 10 

22  50 

Santa  Cruz. 

26  15 

344  06 

Feb.  1836. 

Vaillant. 

22  16 

-PO  15 

22  31 

At  sea. 

27  22 

344  38 

Feb.  1836. 

Vaillant. 

21  44 

-pO  15 

21  59 

At  sea. 

29  15 

345  16 

Sept.  1842. 

Berard. 

22  00 

-0  10 

21  50 

At  sea. 

29  12 

346  05 

Feb.  1836. 

Vaillant. 

22  02 

-PO  15 

22  17 

At  sea. 

Between  the  latitudes  of  20°  and  10°. 

17  56 

283  09 

April  1847. 

Barnett. 

— 3 40 

— 0 10 

— 3 50  Jamaica. 

17  56 

283  09 

Oct.  1837. 

Milne. 

— 4 18 

-pO  03 

— 4 15  Jamaica. 

17  55 

283  44 

1831. 

Austin. 

— 5 13 

-pO  12 

— 5 01 

Point  Morant. 

10  25 

284  25 

Sept.  1837. 

Milne. 

— 5 41 

-pO  04 

— 5 37 

Carthagena. 

19  55 

284  45 

July  1837. 

Milne. 

— 3 31 

-pO  05 

— 3 26 

Cumberland  Harbour. 

11  15 

285  45 

Sept.  1837. 

Milne. 

- 5 29 

-pO  04 

— 5 25 

Santa  Martha. 

19  39 

295  51 

July  1838. 

Berard. 

- 0 01 

+ 0 03 

-p  0 02 

At  sea. 

18  14 

296  51 

1846. 

Barnett. 

— 0 56 

— 0 12 

- 1 08 

Anguilla  Island. 

17  08 

298  08 

Nov.  1840. 

Milne. 

— 0 42 

-0  01 

— 0 43 

Antigua. 

17  08 

298  08 

Jan.  1848. 

Barnett. 

- 0 46 

-0  16 

— 1 02 

Antigua. 

13  05 

300  22 

Nov.  1839. 

Milne. 

- 1 13 

0 00 

_ 1 13 

Barbadoes. 

13  05 

300  24 

1846. 

Schomburgk. 

- 1 27 

— 0 12 

- 1 39 

Barbadoes. 

18  18 

321  24 

May  1846. 

Sulivan. 

-t-11  24 

— 0 32 

-plO  52 

At  seat- 

17  02 

321  51 

May  1846. 

Sulivan. 

9 38 

-0  32 

9 06 

At  seat- 

19  19 

321  51 

May  1839. 

Du  Petit-Thouars. 

11  56 

+ 0 02 

11  58 

At  sea. 

15  21 

322  28 

May  1846. 

Sulivan. 

10  49 

-0  35 

10  14 

At  seat- 

l6  36 

323  27 

May  1839 

Du  Petit-Thouars. 

11  13 

-pO  02 

11  15 

At  sea. 

13  55 

325  01 

May  1839 

Du  Petit-Thouars. 

11  34 

-pO  02 

11  36 

At  sea. 

11  58 

327  30 

May  1839 

Du  Petit-Thouars. 

11  42 

-pO  03 

11  45 

At  sea. 

16  20 

328  52 

July  1830 

Erman. 

12  36 

-pO  54 

13  30 

At  sea. 

18  57 

329  36 

July  1830 

Erman. 

13  02 

-pO  50 

13  52 

At  sea. 

19  22 

329  41 

July  1846 

Berard. 

15  Og 

— 0 38 

14  30 

At  sea. 

15  13 

329  56 

July  1830 

Erman. 

13  Og 

-pO  57 

14  05 

At  sea. 

17  17 

330  40 

July  1846 

Berard. 

17  If 

-0  33 

16  43 

At  sea. 

18  31 

330  57 

Oct.  1837 

Vaillant. 

14  04 

-pO  14 

14  18 

At  sea. 

14  01 

331  11 

July  1830 

Erman. 

12  4C 

+ 1 01 

13  41 

At  sea. 

12  51 

331  31 

July  1830 

Erman. 

12  5^ 

-pi  01 

13  56 

At  sea. 

11  53 

331  43 

July  1830 

Erman. 

12  5f 

-pi  01 

13  57 

At  sea. 

16  39 

332  16 

Oct.  1837 

. Vaillant. 

14  2( 

+ 0 15 

14  3S 

At  sea. 

10  36 

333  00 

July  1830 

. Erman. 

13  3: 

-pi  01 

14  34 

At  sea. 

12  17 

333  35 

May  1832 

. FitzRoy. 

13  4[ 

+ 0 49 

14  3S 

At  sea. 

14  49 

333  41 

Oct.  1837 

. Vaillant. 

14  3^ 

-pO  15 

14  47 

At  sea. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC, 


217 


Table  XII.  (Continued.) 


Observed 

Correc- 

Corrected 

Lat. 

Lone. 

Date. 

Observer. 

Declina- 

tion  for 

DecUna- 

Remarks. 

tion. 

Epoch. 

tion. 

Between  the  latitudes  of  20 

^ and  10'^ 

(continued). 

O 

13 

36 

334 

16 

July  1846. 

Berard. 

O / 

17  04 

O 

— 0 

40 

16  24 

At  sea. 

13 

02 

334 

21 

Sept.  1842. 

Berard. 

13  00 

-0 

17 

12  47 

At  sea. 

13 

38 

334 

26 

Sept.  1842. 

Berard. 

13  50 

-0 

17 

13  37 

At  sea. 

11 

13 

334 

36 

Sept.  1842. 

Berard. 

15  00 

-0 

17 

14  47 

At  sea. 

13 

20 

334 

40 

May  1832. 

FitzRoy. 

14  49 

+ 0 

49 

15  38 

At  sea. 

13 

55 

334 

40 

Oct.  1837. 

Vaillant. 

15  06 

+ 0 

15 

15  18 

At  sea. 

16 

35 

334 

42 

Sept.  1842. 

Berard. 

17  00 

— 0 

17 

16  47 

At  sea. 

10 

00 

334 

44 

Nov.  1839. 

Ross. 

15  47 

0 

00 

15  47 

At  seaf. 

12 

46 

335 

25 

Sept.  1837. 

Vaillant. 

15  23 

+ 0 

14 

15  37 

At  sea. 

12 

12 

335 

30 

Nov.  1839. 

Ross. 

16  26 

0 

00 

16  26 

At  seaf. 

15 

29 

336 

08 

1832. 

FitzRoy. 

15  52 

+ 0 

49 

16  41 

At  sea. 

14 

43 

336 

21 

1836. 

FitzRoy. 

17  02 

+ 0 

21 

17  23 

At  sea. 

15 

17 

336 

25 

1832. 

FitzRoy. 

15  22 

+ 0 

49 

16  11 

At  sea. 

10 

13 

336 

28 

Jan.  1837. 

Du  Pedt-Thouars. 

16  59 

+ 0 

18 

17  17 

At  sea. 

14 

56 

336 

28 

Nov.  1839. 

Ross. 

l6  26 

0 

00 

16  26 

At  seaf. 

14 

54 

336 

30 

1831. 

FitzRoy. 

16  30 

+ 0 

55 

17  25 

Port  Praya. 

13 

36 

336 

37 

July  1846. 

Berard. 

17  04 

— 0 

39 

16  25 

At  sea. 

15 

49 

336 

40 

Jan.  1847. 

Stanley. 

18  04 

— 0 

42 

17  22 

At  seaf. 

11 

59 

336 

47 

Sept.  1837. 

Vaillant. 

16  42 

+ 0 

14 

16  56 

At  sea. 

12 

17 

336 

48 

Jan.  1847. 

Stanley. 

15  55 

— 0 

42 

15  13 

At  seaf. 

17 

50 

336 

50 

1832. 

FitzRoy. 

17  06 

+ 1 

00 

18  06 

At  sea. 

19 

02 

336 

51 

Jan.  1847. 

Stanley. 

20  35 

- 0 

42 

19  33 

At  seaf. 

11 

37 

337 

00 

Jan.  1846. 

Berard. 

16  12 

— 0 

39 

15  33 

At  sea. 

13 

16 

337 

21 

Jan.  1837. 

Du  Petit-Thouars. 

17  32 

+ 0 

18 

17  50 

At  sea. 

12 

48 

337 

39 

July  1846. 

Berard. 

17  35 

-0 

42 

16  53 

At  sea. 

19 

06 

337 

43 

1832. 

FitzRoy. 

17  39 

+ 0 

45 

18  24 

At  sea. 

18 

42 

337 

50 

Nov.  1839. 

Ross. 

17  58 

0 

00 

17  58 

At  seaf. 

19 

31 

338 

03 

1832. 

FitzRoy. 

18  06 

+ 0 

45 

18  51 

At  sea. 

11 

05 

338 

03 

Sept.  1837. 

Vaillant. 

16  13 

+0 

15 

16  28 

At  sea. 

10 

11 

338 

56 

Sept.  1837. 

Vaillant. 

16  27 

+ 0 

15 

16  42 

At  sea. 

11 

05 

338 

59 

Sept.  1837. 

Vaillant. 

16  36 

+0 

15 

16  51 

At  sea. 

16 

51 

339 

39 

Feb.  1836. 

Vaillant. 

19  48 

+ 0 

26 

20  14 

At  sea. 

10 

48 

339 

41 

Sept.  1837. 

Vaillant. 

16  06 

+ 0 

15 

16  21 

At  sea. 

13 

41 

339 

42 

Mar.  1836. 

Vaillant. 

17  12 

+ 0 

25 

17  37 

At  sea. 

19 

40 

340 

09 

Feb.  1836. 

Vaillant. 

19  47 

40 

25 

20  12 

At  sea. 

11 

40 

344 

15 

Oct.  1846. 

Denham. 

19  12 

-0 

40 

18  32 

Guancho. 

11 

33 

344 

21 

Sept.  1846. 

Denham. 

19  10 

— 0 

40 

18  30 

Bulama. 

11 

52 

344 

23 

Sept.  1846, 

Denham. 

20  13 

-0 

40 

19  33 

Bissao. 

Between  the  latitudes  of  10°  and  0°. 

6 

44 

00 

1 

45 

Jan.  1843. 

Schomburgk. 

- 3 59 

— 0 

06 

— 4 05 

JFork  of  Wenama  and  Cuguori 
\ Rivers. 

4 57 

298 

59 

Nov.  1842. 

Schomburgk. 

- 4 11 

— 0 

06 

— 4 17 

Near  Mount  Roraima. 

4 

17 

299 

42 

Oct.  1842. 

Schomburgk. 

- 4 00 

— 0 

05 

— 4 05 

Macusi  Village,  Pakaraima  Mts. 

3 

22 

299 

48 

Sept.  1842. 

Schomburgk. 

— 4 37 

-0 

05 

— 4 42 

f Junction  of  Cotinger  and  Ta- 
f cuter  Rivers. 

8 

25 

300 

24 

April  1841. 

Schomburgk. 

- 2 50 

-0 

03 

— 2 53 

River  Guainia. 

3 

39 

300 

40 

Mar.  1842. 

Schomburgk. 

— 4 00 

-0 

05 

— 45 

Pirara,  River  Rupunuri. 

6 

24 

301 

18 

Dec.  1843. 

Schomburgk. 

- 3 06 

— 0 

08 

- 3 14 

Penal  Settlement. 

6 

49 

301 

49 

Sept.  1841. 

Schomburgk. 

— 2 44 

— 0 

03 

- 2 47 

Georgetown. 

1 

25 

301 

54 

July  1843.:Schomburgk. 

— 3 57 

— 0 

05 

— 4 02 

Rio  Trombetas. 

2 

02 

303 

32 

Aug.  1843JSchomburgk. 

— 3 40 

-0 

06 

- 3 46 

Pianogholo  Village. 

9 

39 

326 

10 

May  1846JSulivan. 

July  1830JErinan. 

+ 12  47 

— 0 

39 

+ 12  08 

At  seaf. 

2 

04 

329 

37 

10  12 

+ 1 

11 

11  23 

At  sea. 

4 

01 

329 

42  July  1830.|Erinan. 

11  08 

+ 1 

11 

12  19 

At  sea. 

218 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Decbna- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  10 

° and  0° 

(continued). 

O 

5 

30 

329 

48 

May  1846. 

Sulivan. 

13 

57 

O 

— 0 

51 

O 

13 

06 

At  seaf. 

4 

45 

330 

08 

May  1846. 

Sulivan. 

12 

53 

-0 

51 

12 

02 

At  seaf. 

2 

05 

330 

11 

May  1846. 

Sulivan. 

12 

45 

-0 

51 

11 

54 

At  seaf. 

8 

22 

330 

16 

May  1839. 

Du  Petit-Thouars. 

13 

04 

+ 0 

05 

13 

09 

At  sea. 

0 

55 

330 

36 

Dec.  1832. 

FitzRoy. 

8 

22 

-fO 

56 

9 

18 

At  sea. 

0 

55 

330 

42 

Dec.  1839. 

Ross. 

11 

50 

0 

00 

11 

50 

St.  Paul’s  Rocks. 

3 

39 

330 

49 

July  1836. 

FitzRoy. 

10 

27 

+0 

28 

10 

55 

At  sea. 

2 

32 

330 

53 

Dec.  1836. 

FitzRoy. 

10 

23 

+ 0 

24 

10 

47 

At  sea. 

1 

20 

330 

55 

Dec.  1832. 

FitzRoy. 

10 

39 

+ 0 

56 

11 

35 

At  sea. 

3 

48 

330 

58 

May  1846. 

Sulivan. 

13 

04 

— 0 

51 

12 

13 

At  seaf. 

2 

49 

331 

06 

May  1846. 

Sulivan. 

12 

58 

-0 

51 

12 

07 

At  seaf. 

] 

57 

331 

38 

Nov.  1839. 

Ross. 

13 

16 

0 

00 

13 

16 

At  seaf. 

2 

10 

332 

10 

Dec.  1832. 

FitzRoy. 

11 

08 

+ 0 

56 

12 

04 

At  sea. 

! 3 

18 

332 

46 

Nov.  1839. 

Ross. 

12 

18 

0 

00 

12 

18 

At  seaf. 

5 

45 

332 

49 

1836. 

FitzRoy. 

11 

26 

4-0 

28 

11 

54 

At  sea. 

8 

50 

332 

58 

1832. 

FitzRoy. 

12 

44 

+ 0 

56 

13 

40 

At  sea. 

1 5 

26 

332 

59 

May  1839. 

Du  Petit-Thouars. 

14 

30 

+ 0 

05 

14 

35 

At  sea. 

8 

58 

333 

21 

July  1830. 

Erman. 

12 

21 

+ 1 

01 

13 

22 

At  sea. 

6 

46 

333 

52 

Nov.  1839. 

Ross. 

14 

58 

0 

00 

14 

58 

At  seaf. 

3 

37 

333 

52 

Jan.  1837. 

Du  Petit-Thouars. 

13 

19 

+ 0 

24 

13 

43 

At  sea. 

5 

13 

334 

35 

Jan.  1837. 

Du  Petit-Thouars. 

15 

14 

4-0 

24 

15 

38 

At  sea. 

2 

51 

334 

38 

May  1839. 

Du  Petit-Thouars. 

14 

10 

-hO 

05 

14 

15 

At  sea. 

9 

36 

335 

04 

Sept.  1842. 

Berard. 

15 

00 

-0 

17 

14 

43 

At  sea. 

7 

24 

335 

32 

Jan.  1837. 

Du  Petit-Thouars. 

16 

02 

+ 0 

19 

16 

21 

At  sea. 

0 

09 

335 

35 

May  1839. 

Du  Petit-Thouars. 

14 

53 

+0 

05 

14 

58 

At  sea. 

8 

19 

386 

05 

Sept.  1842. 

Berard. 

15 

30 

-0 

17 

15 

13 

At  sea. 

7 

09 

336 

51 

Sept.  1842. 

Berard. 

15 

30 

-0 

17 

15 

13 

At  sea. 

6 

48 

336 

52 

Sept.  1842. 

Berard. 

14 

00 

-0 

17 

13 

43 

At  sea. 

9 

24 

337  22 

Jan.  1847. 

Stanley. 

16 

06 

-0 

45 

15 

21 

At  seaf. 

6 

40 

337 

22 

Jan.  1847. 

Stanley. 

16 

52 

— 0 

49 

16 

03 

At  seaf. 

5 

50 

337 

25 

July  1846. 

Berard. 

15 

11 

-0 

45 

14 

26 

At  sea. 

3 

26 

337 

33 

Jan.  1847. 

Stanley. 

17 

00 

-0 

49 

16 

11 

At  seaf. 

1 

11 

337 

35 

Jan.  1847. 

Stanley. 

16 

14 

— 0 

49 

15 

25 

At  seaf. 

4 

38 

3.38 

00 

Sept.  1842. 

Berard. 

15 

00 

-0 

17 

14 

43 

At  sea. 

4 

34 

338 

02 

Jan.  1847. 

Stanley. 

17 

00 

-0 

49 

16 

11 

At  seaf. 

1 

19 

338 

07 

Oct.  1842. 

Berard. 

16 

30 

-0 

19 

16 

11 

At  sea. 

2 

08 

338 

09 

Jan.  1847. 

Stanley. 

16 

07 

-0 

56 

15 

11 

At  seaf. 

4 

19 

338 

14 

Jan.  1847. 

Stanley. 

16 

31 

-0 

56 

15 

35 

At  seaf. 

4 

56 

338 

38 

Sept.  1842. 

Berard. 

14 

20 

-0 

19 

14 

01 

At  sea. 

8 

45 

338 

53 

Mar.  1836. 

Vaillant. 

17 

13 

+ 0 

23 

17 

36 

At  sea. 

9 

33 

339 

19 

Sept.  1837. 

Vaillant. 

16 

46 

4-0 

15 

17 

01 

At  sea. 

5 

17 

339 

20 

Sept.  1842. 

Berard. 

15 

00 

4-0 

19 

15 

19 

At  sea. 

6 

21 

339 

21 

Mar.  1836. 

Vaillant. 

17 

13 

+0 

23 

17 

36 

At  sea. 

8 

48 

339  24 

Sept.  1837. 

Vaillant. 

16 

39 

+ 0 

15 

16 

54 

At  sea. 

0 

46 

339 

26 

Jan.  1846. 

Berard. 

16 

46 

-0 

49 

15 

57 

At  sea. 

3 

14 

340 

09 

Sept.  1842. 

Berard. 

15 

30 

-0 

18 

15 

12 

At  sea. 

2 

50 

340 

13 

Mar.  1836. 

Vaillant. 

17 

47 

-fO 

23 

18 

10 

At  sea. 

0 

43 

340 

14 

Mar.  1836. 

Vaillant. 

17 

12 

+ 0 

23 

17 

35 

At  sea. 

2 

50 

340 

40 

Sept.  1842. 

Berard. 

15 

30 

-0 

18 

15 

12 

At  sea. 

8 

21 

340 

55 

Sept.  1837. 

Berard. 

17 

21 

-fO 

15 

17 

36 

At  sea. 

6 

18 

341 

50 

Sept.  1837. 

Berard. 

16 

18 

+0 

15 

16 

33 

At  sea. 

4 

30 

342  06 

Sept.  1837 

Berard. 

16 

42 

+ 0 

15 

16 

57 

At  sea. 

0 

34 

343 

22 

Sept.  1837 

Berard. 

17 

15 

+ 0 

14 

17 

29 

At  sea. 

9 

27 

346 

12 

Jan.  1836. 

Vidal. 

17 

43 

+ 0 

24 

18 

07 

Isles  de  Los. 

8 

30 

346 

44 

Feb.  1836. 

Vidal. 

18 

52 

+ 0 

24 

19 

16 

Sierra  Leone. 

8 

30 

346 

44 

June  1836. 

Vidal. 

19 

06 

+ 0 

21 

19 

27 

Sierra  Leone. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


219 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  10°  and  0° 

(continued). 

O 

8 

30 

346 

44 

Dec.  1836. 

Vidal. 

20 

12 

O 

+ 0 

18 

20 

30 

Sierra  Leone. 

8 

30 

346 

44 

Sept.  1836. 

Denham. 

19 

36 

-0 

33 

19 

03 

Sierra  Leone. 

7 

39 

346 

56 

Dec.  1836. 

Vidal. 

19 

17 

+ 0 

18 

19 

35 

Moot  Island. 

7 

00 

348 

21 

Dec.  1837. 

Vidal. 

18 

53 

+0 

] 1 

19 

04 

Gallinas. 

6 

19 

349 

11 

Dec.  1837. 

Vidal. 

19 

29 

+ 0 

11 

19 

40 

Cape  Mesurada. 

6 

09 

349 

11 

Jan.  1837. 

Vidal. 

20 

07 

+ 0 

16 

20 

23 

Monrovia. 

4 

22 

352 

16 

Feb.  1836. 

Vidal. 

20 

00 

+ 0 

11 

20 

11 

Cape  Palmas. 

4 

22 

.352 

16 

Dec.  1845. 

Denham. 

19 

05 

-0 

18 

18 

47 

Cape  Palmas. 

4 

45 

337 

54 

May  1837. 

Vidal. 

20 

03 

0 

00 

20 

03 

Cape  Three  Points. 

4 

48 

358 

03 

Aprill838. 

Vidal. 

20 

37 

0 

00 

20 

37 

Dix  Cove. 

3 

06 

358 

46 

Aprill838. 

Vidal. 

20 

11 

0 

00 

20 

11 

Cape-Coast  Castle. 

5 

10 

358 

54 

Aprill838. 

Vidal. 

20 

13 

0 

00 

20 

13 

Annamaboe. 

5 

32 

359 

49 

Aprill838. 

Vidal. 

20 

18 

0 

00 

20 

18 

Accra. 

5 

32 

359 

49 

Jan.  1846. 

Denham. 

20 

39 

0 

00 

20 

39 

Accra. 

5 

55 

1 

00 

May  1846. 

Denham. 

19 

55 

0 

00 

19 

55 

Quitta. 

6 

13 

1 

36 

Jan.  1846. 

Denham. 

20 

21 

0 

00 

20 

21 

Little  Popoe. 

6 

19 

2 

05 

Jan.  1846. 

Denham. 

20 

08 

0 

00 

20 

08 

Whydah. 

6 

24 

2 

53 

Jan.  1846. 

Denham. 

20 

30 

0 

00 

20 

30 

Badagry. 

4 

32 

5 

41 

May  1846jDenham. 

19 

50 

0 

00 

19 

50 

Middleton  River. 

7 

07 

7 

49 

1835.1  Allen. 

19 

51 

0 

00 

19 

51 

Sterling. 

3 

46 

8 

45 

Mar.  1836.1  Vidal. 

19 

45 

0 

00 

19 

45 

Point  William. 

3 

35 

8 

45 

Mar.  1836.  Vidal. 

19 

50 

0 

00 

19 

50 

Fernando  Po. 

3 

46 

8 

48 

Jan.  1846.  Denham. 

19 

04 

0 

00 

19 

04 

Fernando  Po. 

6 27 

9 

13 

1835. 

Allen. 

20 

36 

0 

00 

20 

36 

Rabba. 

0 

55 

9 

20 

Mar.  1836.]  Vidal. 

20 

04 

0 

00 

20 

04 

Corisco  Bay. 

3 

55 

9 

30 

Aprill  836.1  Vidal. 

19 

46 

0 

00 

19 

46 

Cameroons  River. 

Between  the  latitudes 

of  0° 

and  -10°. 

-1 

28 

311 

36 

Sept.  1830. 

Foster. 

— 1 

14 

+0 

57 

- 0 

17 

Para. 

— 2 

31 

315 

48 

Aug.  1830. 

Foster. 

+ 0 

31 

+0 

57 

+ 1 

28 

Maranham. 

— 0 

58 

319 

26 

Aug.  1842. 

Jehenne. 

5 

47 

— 0 

17 

5 

30 

At  sea. 

—3 

18 

321 

36 

Aug.  1842. 

Jehenne. 

6 

24 

-0 

17 

6 

07 

At  sea. 

-3 

41 

323 

46 

Aug.  1842. 

Jehenne. 

6 

47 

-0 

19 

6 

28 

At  sea. 

-8 

04 

325 

08 

Aug.  1836. 

FitzRoy. 

5 

54 

+0 

34 

6 

28 

Pernambuco. 

-8 

03 

325 

10 

Aug.  1836. 

FitzRoy. 

5 

10 

+ 0 

34 

5 

44 

At  sea. 

-7  28 

326 

48 

Jan.  1837. 

Du  Fetit-Thouars. 

9 

45 

+0 

28 

10 

13 

At  sea. 

-3 

31 

327 

26 

Jan.  1837- 

Du  Petit-Thouars. 

9 

30 

+ 0 

27 

9 

57 

At  sea. 

-7 

16 

327 

27 

Dec.  1839. 

Ross. 

8 

57 

0 

00 

8 

57 

At  seaf. 

-3 

31 

327 

35 

Feb.  1832. 

FitzRoy. 

7 

53 

+ 1 

21 

9 

14 

Fernando  de  Noronha. 

—2  36 

327 

52 

Jan.  1837. 

Du  Petit-Thouars. 

10 

10 

+ 0 

27 

10 

37 

At  sea. 

— 3 

09 

327 

58 

Feb.  1832. 

FitzRoy. 

7 

54 

+ 1 

20 

9 

14 

At  sea. 

— 5 

04 

327 

59 

Feb.  1832. 

FitzRoy. 

7 

45 

+ 1 

20 

9 

05 

At  sea. 

-9 

40 

328 

01 

July  1830. 

Erman. 

8 

39 

+ 1 

35 

10 

14 

At  sea. 

-3 

29 

328 

03 

Feb.  1832. 

FitzRoy. 

8 

00 

+ 1 

15 

9 

15 

At  sea. 

-9  47 

328 

07 

Dec.  1839. 

Ross. 

8 

39 

0 

00 

8 

39 

At  seat- 

-7  57 

328 

31 

July  1830. 

Erman. 

9 

01 

+1 

38 

10 

39 

At  sea. 

-3 

02 

328 

41 

Dec.  1839. 

Ross. 

10 

15 

0 

00 

10 

15 

At  seat- 

-6 

21 

328 

57 

July  1830. 

Erman. 

8 

53 

+ 1 

38 

10 

31 

At  sea. 

-9  47 

329 

04 

May  1846. 

Sulivan. 

9 

03 

— 1 

14 

7 

49 

At  seat- 

—8 

18 

329 

05 

May  1846. 

Sulivan. 

9 

27 

-1 

14 

8 

13 

At  seat- 

— 5 

02 

329 

06 

Aug.  1842. 

Jehenne. 

9 

27 

-0 

27 

9 

00 

At  sea. 

-6 

46 

329 

07 

May  1846. 

Sulivan. 

9 

46 

— 1 

05 

8 

41 

At  seat- 

—3 

18 

329 

11 

May  1846. 

Sulivan. 

9 

50 

— 1 

00 

8 

50 

At  seat- 

—5 

10 

329 

16 

May  1846. 

Sulivan. 

9 

46 

— 1 

04 

8 

42 

At  seat- 

— 3 

23 

329 

16 

July  1830. 

Erman. 

9 

17 

+ 1 

25 

10 

42 

At  sea. 

220 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  0°  and  - 

-10' 

(continued). 



0 

1 

04 

329 

20 

Jan.  1837.!du  Petit-Thouars. 

O 

12 

20 

O 

+ 0 

26 

O 

12 

46 

At  sea. 

— 

1 

21 

329 

29 

July  1830. 

Erman. 

9 

19 

+ 1 

21 

10 

40 

At  sea. 

— 

2 

50 

329 

34 

May  1846. 

Sulivan. 

10 

18 

—1 

00 

9 

18 

At  seaf . 

— 

0 

35 

329 

42 

July  1830. 

Erman. 

9 

51 

+ 1 

21 

11 

12 

At  sea. 

— 

0 

28 

329 

42 

Feb.  1832. 

FitzRoy. 

8 

10 

+ 1 

15 

9 

25 

At  sea. 

— 

0 

01 

330 

01 

Feb.  1832. 

FitzRoy. 

8 

58 

+ 1 

15 

10 

13 

At  sea. 

— 

0 

46 

330 

03 

May  1846. 

Sulivan. 

10 

54 

-0 

55 

9 

59 

At  seaf. 

— 

0 

07 

330 

08 

Dec.  1839. 

Ross. 

10 

35 

0 

00 

10 

35 

At  seaf. 

— 

9 

18 

330 

30 

Oct.  1842. 

Berard. 

11 

00 

-0 

27 

10 

33 

At  sea. 

— 

7 

47 

330 

48 

Jan.  1847. 

Stanley. 

13 

41 

— 1 

17 

12 

24 

At  seaf. 

— 

5 

59 

331 

08 

Aug.  1842, 

Jehenne. 

13 

04 

-0 

25 

12 

39 

At  sea. 

— 

7 

02 

332 

02 

Oct.  1842. 

Berard. 

13 

00 

— 0 

25 

12 

35 

At  sea. 

— 

4 

58 

332 

10 

Jan.  1847. 

Stanley. 

14 

34 

— 1 

11 

13 

23 

At  seaf. 

— 

8 

02 

333 

44 

Sept.  1836. 

Vaillant. 

U 

30 

+ 0 

33 

12 

03 

At  sea. 

— 

2 

34 

333 

50 

Jan.  1847. 

Stanley. 

14 

27 

— 1 

05 

13 

22 

At  seaf. 

— 

3 

10 

334 

09 

Oct.  1842. 

Berard. 

15 

45 

— 0 

24 

15 

21 

At  sea. 

— 

1 

40 

335 

01 

Oct.  1842. 

Berard. 

15 

00 

-0 

24 

14 

36 

At  sea. 

— 

5 

15 

335 

26 

1836. 

Vaillant. 

13 

46 

+ 0 

35 

14 

21 

At  sea. 

— 

0 

41 

335 

40 

Oct.  1842. 

Berard. 

15 

00 

-0 

24 

14 

36 

At  sea. 

— 

7 

48 

335 

46 

Aug.  1 842. 

Jehenne. 

14 

29 

-0 

26 

14 

03 

At  sea. 

— 

0 

19 

335 

50 

Jan.  1847. 

Stanley. 

15 

05 

— 1 

10 

13 

55 

At  seaf. 

— 

1 

52 

336 

43 

May  1839. 

Du  Petit-Thouars. 

14 

48 

+ 0 

04 

14 

52 

At  sea. 

— 

3 

38 

337 

28 

Mar.  1836. 

Vaillant. 

14 

30 

+ 0 

36 

15 

06 

At  sea. 

— 

3 

18 

338 

45 

May  1839. 

Du  Petit-Thouars. 

15 

58 

+ 0 

04 

16 

02 

At  sea. 

— 

1 

15 

340 

01 

.Mar.  1836. 

Vaillant. 

14 

37 

+ 0 

33 

15 

10 

At  sea. 

— 

0 

40 

340 

10 

Jan.  1846. 

Berard. 

17 

17 

-0 

52 

16 

25 

At  sea. 

— 

2 56 

341 

10 

Jan.  1846. 

Berard. 

17 

47 

-0 

52 

16 

55 

At  sea. 

— 

4 

29 

341 

16 

May  18.39. 

Du  Petit-Thouars. 

16 

33 

+ 0 

05 

16 

38 

At  sea. 

— 

9 

30 

342 

28 

1836. 

FitzRoy. 

15 

56 

+ 0 

35 

16 

31 

At  sea. 

— 

4 

45 

342 

39 

Jan.  1846. 

Berard. 

19 

01 

— 0 

54 

18 

07 

At  sea. 

— 

5 

55 

344 

18 

May  1839. 

Du  Petit-Thouars. 

18 

46 

+0 

05 

18 

51 

At  sea. 

— 

6 

38 

344 

19 

Jan.  1846. 

Berard. 

19 

27 

-0 

54 

18 

33 

At  sea. 

— 

1 

51 

344 

47 

Sept.  1837. 

Vaillant. 

17 

47 

+ 0 

20 

18 

07 

At  sea. 

— 

0 

44 

344 

58 

Sept.  1837. 

Vaillant. 

17 

34 

+ 0 

20 

17 

54 

At  sea. 

— 

5 

12 

345 

04 

Sept.  1837. 

Vaillant. 

18 

52 

+ 0 

22 

19 

14 

At  sea. 



2 

56 

345 

13 

Sept.  1837. 

Vaillant. 

17 

53 

+ 0 

20 

18 

13 

At  sea. 

— 

7 55 

345 

35 

June  1846. 

Berard. 

19 

16 

-0 

58 

18 

18 

Anchorage,  Ascension. 

— 

7 

54 

345 

36 

May  1839. 

Du  Petit-Thouars. 

18 

31 

+ 0 

04 

18 

35 

Anchorage,  Ascension. 

7 

54 

345 

36 

18.36. 

FitzRoy. 

17 

36 

+ 0 

31 

18 

07 

Anchorage,  Ascension. 

— 

7 

11 

345 

39 

Sept.  1837. 

Vaillant. 

19 

13 

+ 0 

20 

19 

33 

At  sea. 

— 

8 

17 

346 

09 

May  1839. 

Du  Petit-Thouars. 

18 

54 

+ 0 

04 

18 

58 

At  sea. 

— 

8 

49 

346 

30 

Sept.  1837. 

Vaillant. 

17 

58 

+ 0 

20 

18 

18 

At  sea. 

— 

9 

52 

347 

26 

1836. 

FitzRoy. 

17 

43 

+ 0 

31 

18 

14 

At  sea. 

— 

9 

30  347 

48 

June  1846. 

Berard. 

19 

16 

— 0 

58 

18 

18 

At  sea. 

— 

9 

49:  347 

55 

May  1839. 

Du  Petit-Thouars. 

19 

37 

+ 0 

04 

19 

41 

At  sea. 

— 

1 

21 

5 

38 

1829. 

Boteler. 

21 

01 

+0 

31 

21 

32 

Anno  Bona. 

Between  the  latitud 

es  ol 

— 1 0°  a 

id  — 

o 

o 

18 

25 

321 

05 

Dec.  1843. 

Pasley. 

3 

10 

— 0 

38 

2 

32 

At  sea. 



18 

14 

321 

08 

1832. 

FitzRoy. 

1 

04 

+ 1 

10 

2 

14 

At  sea. 

— 

17 

13 

321 

12 

1832. 

FitzRoy. 

1 

08 

+ 1 

10 

2 

18 

At  sea. 



16 

35 

321 

12 

1832. 

FitzRoy. 

1 

52 

+ 1 

10 

3 

02 

At  sea. 

— 

18 

59 

321 

16 

1832. 

F'itzRoy. 

1 

14 

+ 1 

10 

2 

24 

At  sea. 



17 

58 

321 

18 

Mar.  1832. 

FitzRoy. 

2 

00 

+ 1 

13 

3 

13 

Abrolhos  Island. 



15 

01 

321 

19 

1832. 

FitzRoy. 

1 

30 

+ 1 

10 

2 

40 

At  sea. 

— 

13 

25 

321 

23 

1832. 

FitzRoy. 

2 

08 

+ 1 

10 

3 

18 

At  sea. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


221 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion, 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes 

of  -10° 

and  —20°  (continued). 

— 18  03 

o / 

321  24 

1832. 

FitzRoy. 

2 12 

o / 

+ 1 10 

3 22 

At  sea. 

— 13  11 

321  29 

1832. 

FitzRoy. 

2 09 

+ 1 10 

3 19 

At  sea. 

-12  59 

321  29 

Feb.  1832. 

FitzRoy. 

4 18 

-1-1  14 

5 32 

Bahia. 

-12  59 

321  30 

Oct.  1842. 

Berard. 

3 30 

— 0 25 

3 05 

At  sea. 

-13  09, 

.321  30 

1836.  FitzRoy. 

2 44 

-fO  33 

3 17 

At  sea. 

— 13  33 

321  35 

1832. 

FitzRoy. 

1 34 

-fl  10 

2 44 

At  sea. 

— 15  27 

321  36 

1832. 

FitzRoy. 

2 48 

-1-1  10 

3 58 

At  sea. 

— 16  20 

321  36 

1832. 

FitzRoy. 

1 59 

+ l 10 

3 09 

At  sea. 

-13  39 

321  36  ; 

Oct.  1842. 

Berard. 

4 00 

-0  25 

3 35 

At  sea. 

— 17  33 

321  37 

1832. 

FitzRoy. 

2 16 

-HI  10 

3 26 

At  sea. 

— 14  42 

321  38 

1832. 

FitzRoy. 

2 20 

-HI  10 

3 30 

At  sea. 

— 14  22 

321  51 

Oct.  1842. 

Berard. 

4 30 

-0  25 

4 05 

At  sea. 

— 12  38 

322  14 

1836. 

FitzRoy. 

3 14 

-HO  32 

3 46 

At  sea. 

— 16  25 

322  21 

Oct.  1842. 

Berard. 

3 00 

-0  25 

2 35 

At  sea. 

— 17  54 

322  29 

1832jFitzRoy. 

2 20 

-HI  10 

3 30 

At  sea. 

— 12  42 

322  35 

Oct.  1842. 

Berard, 

7 00 

-0  25 

6 35 

At  sea. 

— 15  20 

322  38 

1832. 

FitzRoy. 

3 03 

+ 1 10 

4 13 

At  sea. 

— 12  42 

322  45 

1836. 

FitzRoy. 

3 31 

-HO  32 

4 03 

At  sea. 

-16  29 

323  03 

1832. 

FitzRoy. 

3 44 

+ 1 10 

4 54 

At  sea. 

— 17  42 

323  06 

Oct.  1842. 

Berard. 

4 30 

-0  27 

4 03 

At  sea. 

— 12  48 

323  13 

1836, 

FitzRoy. 

4 18 

-HO  32 

4 50 

At  sea. 

-17  47 

323  24 

Jan.  1837. 

Du  Petit-Thouars. 

7 20 

+ 0 29 

7 49 

At  sea. 

— 17  41 

323  43 

Jan.  1847. 

Stanley. 

7 00 

-1  06 

5 54 

At  seaf. 

-19  38 

323  49 

Oct.  1842. 

Berard. 

3 45 

-0  27 

3 18 

At  sea. 

— 18  10 

324  04 

1832, 

FitzRoy. 

3 01 

+ 1 11 

4 12 

At  sea. 

— 18  48 

324  17 

Mar.  1836. 

Vaillant. 

3 41 

-HO  35 

4 16 

At  sea. 

-11  54 

324  22 

Oct.  1842. 

B6rard. 

8 20 

-0  27 

7 53 

At  sea. 

— 18  57 

324  24 

July  1830. 

Erman. 

4 21 

-HI  35 

5 56 

At  sea. 

— 15  10 

324  45 

Jan.  1837. 

Du  Petit-Thouars. 

7 35 

-HO  28 

8 03 

At  sea.  • 

-19  45 

324  50 

July  1830. 

Erman. 

3 25 

-bl  35 

5 00 

At  sea. 

-19  35 

324  59 

July  1830. 

Erman. 

4 06 

-Hi  35 

5 41 

At  sea. 

-11  46 

325  25 

Oct.  1842. 

Berard. 

8 40 

-0  26 

8 14 

At  sea. 

-14  52 

325  26 

Jan.  1847. 

Stanley. 

8 13 

— 1 06 

7 07 

At  seaf. 

-17  49 

325  36 

July  1830. 

Erman. 

4 41 

-HI  35 

6 16 

At  sea. 

-16  48 

325  42 

Mar.  1836. 

Vaillant. 

4 56 

-HO  35 

5 31 

At  sea. 

— 11  55 

325  50 

Jan.  1837. 

Du  Petit-Thouars. 

8 12 

+ 0 28 

8 40 

At  sea. 

— 16  45 

326  02 

July  1830. 

Erman. 

5 15 

-Hi  35 

6 54 

At  sea. 

-14  43 

326  49 

July  1830. 

Erman. 

6 29 

-Hi  35 

8 04 

At  sea. 

— 15  12 

326  52 

Mar.  1836. 

Vaillant. 

6 45 

+ 0 38 

7 23 

At  sea. 

— 13  01 

327  25 

July  1830. 

Erman. 

7 00 

-Hi  35 

8 35 

At  sea. 

-11  21 

327  45 

July  1830. 

Erman. 

7 18 

+ 1 35 

8 53 

At  sea. 

-10  49 

327  46 

Oct.  1842. 

Berard. 

10  45 

— 0 27 

10  18 

At  sea. 

— 12  48 

.327  58 

Jan.  1847. 

Stanley. 

9 01 

-1  10 

7 51 

At  seaf. 

— 13  15 

328  35 

Mar.  1836. 

Vaillant. 

8 06 

-HO  38 

8 44 

At  sea. 

— 12  28 

329  00 

Dec.  1839. 

Ross. 

8 25 

0 00 

8 25 

At  seaf. 

— 18  11 

329  06 

May  1846. 

Sulivan, 

9 11 

— 1 08 

8 03 

At  seaf. 

— 12  29 

329  08 

May  1846. 

Sulivan. 

9 13 

— 1 08 

8 05 

At  seaf. 

— 15  35 

329  16 

May  1846. 

Sulivan. 

8 31 

— 1 08 

7 23 

At  seaf. 

-17  20 

329  16 

May  1846. 

Sulivan. 

9 01 

-1  08 

7 53 

At  seaf. 

— 14  17 

329  19 

May  1846. 

Sulivan. 

9 00 

-1  08 

7 52 

At  seaf. 

— 10  15 

329  25 

Jan.  1847. 

Stanley. 

12  28 

— 1 12 

11  16 

At  seaf. 

— 14  55 

329  53 

Dec.  1839 

Ross, 

8 33 

0 00 

8 33 

At  seaf. 

-19  02 

329  58 

May  1846 

Sulivan. 

8 58 

— 1 08 

7 50 

At  seaf. 

-11  46 

330  28 

Mar.  1836 

Vaillant. 

8 00 

-HO  40 

8 40 

At  sea. 

— 16  57 

330  30 

Dec.  1839 

Ross. 

9 09 

0 00 

9 09 

At  seaf. 

-19  07 

330  42 

Dec.  1839 

Ross. 

9 48 

0 00 

9 48 

At  seaf. 

-12  08 

331  05 

1836 

FitzRoy. 

8 40 

+ 0 36 

9 16 

At  sea. 

2 G 


MDCCCXLIX. 


222 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

10° 

and 

—20°  (continued). 

O 

-10 

05 

331 

49 

Mar.  1836. 

Vaillant. 

O 

9 

24 

O 

+0 

40 

O 

10 

04 

At  sea. 

— 11 

25 

336 

37 

1836. 

FitzRoy. 

13 

06 

+ 0 

36 

13 

42 

At  sea. 

— 10 

06 

340 

27 

Aug.  1842. 

Jehenne. 

15 

23 

-0 

28 

14 

55 

At  sea. 

-10  07 

341 

02 

1836. 

FitzRoy. 

15 

57 

+ 0 

38 

16 

35 

At  sea. 

— 11 

10 

342 

37 

Aug.  1842. 

Jehenne. 

16 

00 

— 0 

28 

15 

32 

At  sea. 

-11 

59 

344 

10 

June  1846. 

Berard. 

21 

00 

-1 

10 

19 

50 

At  sea. 

-12 

09 

345 

01 

Aug.  1842. 

Jehenne. 

17 

36 

-0 

28 

17 

08 

At  sea. 

-19 

20 

345 

44 

Jan.  1840. 

Ross. 

18 

44 

0 

00 

18 

44 

At  seaf. 

-18 

43 

346 

00 

Jan.  1840. 

Ross. 

17 

46 

0 

00 

17 

46 

At  seaf. 

-17 

37 

346 

23 

Jan.  1840. 

Ross. 

19 

26 

0 

00 

19 

26 

At  seaf. 

-17 

08 

346 

43 

Jan.  1840. 

Ross. 

20 

12 

0 

00 

20 

12 

At  seaf. 

-13 

07 

347 

00 

Aug.  1842. 

Jehenne. 

19 

41 

-0 

26 

19 

15 

At  sea. 

-16 

41 

347 

07 

Jan.  1840. 

Ross. 

19 

32 

0 

00 

19 

32 

At  seaf. 

-16 

22 

347 

25 

Jan.  1840. 

Ross. 

18 

18 

0 

00 

18 

18 

At  seaf. 

-10 

34 

347 

55 

Sept.  1837. 

Vaillant. 

18 

05 

+ 0 

24 

18 

29 

At  sea. 

-15 

22 

347 

58 

Jan.  1840. 

Ross. 

20 

52 

0 

00 

20 

52 

At  seaf. 

-15 

24 

348 

06 

Jan.  1840. 

Ross. 

20 

40 

0 

00 

20 

40 

At  seat* 

— 15 

31 

348 

15 

Jan.  1840. 

Ross. 

20 

16 

0 

00 

20 

16 

At  seaf. 

-15 

44 

348 

15 

Jan.  1840. 

Ross. 

19 

10 

0 

00 

19 

10 

At  seaf. 

— 15 

37 

348 

27 

Jan.  1840. 

Ross. 

19 

11 

0 

00 

19 

11 

At  seaf. 

— 15 

40 

348 

35 

Jan.  1840. 

Ross. 

18 

56 

0 

00 

18 

56 

At  seaf. 

— 11 

22 

349 

32 

May  1839. 

Du  Petit-Thouars. 

20 

14 

+ 0 

06 

20 

20 

At  sea. 

-12 

25 

349 

43 

Sept.  1837. 

Vaillant. 

18 

40 

+0 

23 

19 

03 

At  sea. 

— 14 

22 

349 

54 

Jan.  1840. 

Ross. 

19 

31 

0 

00 

19 

31 

At  seaf. 

— 14 

11 

350 

28 

Jan.  1840. 

Ross. 

21 

24 

0 

00 

21 

24 

At  seaf. 

— 14 

38 

350 

30 

Jan.  1840. 

Ross. 

21 

33 

0 

00 

21 

33 

At  seaf. 

-13 

02 

350 

53 

1836. 

FitzRoy. 

19 

56 

+ 0 

33 

20 

29 

At  sea. 

— 12 

40 

351 

06 

May  1839. 

Du  Petit-Thouars. 

21 

16 

+0 

06 

21 

22 

At  sea. 

— 14 

08 

351 

32 

Jan.  1840. 

Ross. 

21 

32 

0 

00 

21 

32 

At  seaf. 

— 14 

36 

351 

53 

Jan.  1840. 

Ross. 

21 

08 

0 

00 

21 

08 

At  seaf. 

-15 

04 

351 

57 

Jan.  1840. 

Ross. 

21 

10 

0 

00 

21 

10 

At  seaf. 

-14 

11 

352 

00 

Jan.  1840. 

Ross. 

21 

06 

0 

00 

21 

06 

At  seaf. 

— 13 

34 

352 

02 

Jan.  1840. 

Ross. 

22 

09 

0 

00 

22 

09 

At  seaf. 

— 15 

26 

352 

20 

Jan.  1840. 

Ross. 

21 

39 

0 

00 

21 

39 

At  seat- 

— 15  27 

352 

30 

Jan.  1840. 

Ross. 

21 

27 

0 

00 

21 

27 

At  seaf. 

— 14 

28 

352 

52 

May  1839. 

Du  Petit-Thouars. 

22 

18 

+ 0 

05 

22 

23 

At  .sea. 

— 18 

29 

352 

55 

Feb.  1840. 

Ross. 

23 

11 

0 

00 

23 

11 

At  seaf. 

-17 

38 

353 

19 

Feb.  1840. 

Ross. 

21 

37 

0 

00 

21 

37 

At  seaf. 

— 15 

15 

353 

21 

Jan.  1840. 

Ross. 

21 

29 

0 

00 

21 

29 

At  seaf. 

-17 

10 

353 

33 

Feb.  1840. 

Ross. 

20 

54 

0 

00 

20 

54 

At  seaf. 

— 15 

21 

354 

07 

Jan.  1840. 

Ross. 

23 

27 

0 

00 

23 

27 

At  seaf. 

-15 

55 

354 

17 

Feb.  1840. 

Ross. 

22 

53 

0 

00 

22 

53 

Anchorage  at  St.  Helena. 

— 15 

55 

354 

17 

June  1846. 

Berard. 

23 

11 

-0 

58 

22 

13 

Anchorage  at  St.  Helena. 

— 15 

55 

354 

17 

May  1839. 

Du  Petit-Thouars. 

22 

17 

+ 0 

06 

22 

23 

Anchorage  at  St.  Helena. 

-15 

57 

354 

19 

Jan.  1841. 

Magnetical  Observ. 

22 

51 

— 0 

09 

22 

42 

St.  Helena. 

— 15 

57 

354 

26 

1836. 

FitzRoy. 

19 

43 

+ 0 

33 

20 

16 

At  sea. 

-16  27 

355 

24 

Aug.  1842. 

Jehenne. 

24 

03 

— 0 

25 

23 

38 

At  sea. 

-19 

27 

355 

32 

June  1846. 

Berard. 

23 

20 

— 1 

01 

22 

19 

At  sea. 

-16 

13 

355 

34 

June  1846. 

Berard. 

23 

11 

— 1 

01 

22 

10 

At  sea. 

-18 

59 

356 

05 

June  1846. 

Berard. 

23 

20 

— 1 

01 

22 

19 

At  sea. 

-17  04 

356 

33 

Sept.  1837. 

Vaillant. 

22 

28 

+ 0 

22 

22 

50 

At  sea. 

-17 

13 

356 

45 

June  1846. 

Berard. 

23 

21 

— 1 

01 

22 

20 

At  sea. 

-18 

12 

356 

55 

June  1846. 

Berard. 

24 

59 

-1 

01 

23 

58 

At  sea- 

— 18 

52 

.357 

15 

Aug.  1842. 

Jehenne. 

25 

15 

— 0 

25 

25 

20 

At  sea. 

-29 

00 

300 

56 

Jan.  1846. 

Sulivan. 

-10 

40 

-0 

24 

— 11 

04jRio  Parana. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


223 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 20°  and 

— 

1 CO 

o 

o 

-27  27 

301 

16 

Jan.  1846. 

Sulivan. 

O 

9 

24 

O 

-0 

24 



O 

9 

48 

Corrientes  Fort. 

—27  26 

311 

25 

June  1832. 

FitzRoy. 

— 

6 

30 

+ 1 

00 

— 

5 

30 

St.  Catherine. 

-29 

53 

311 

48 

June  1832. 

FitzRoy. 

— 

6 

27 

+ 1 

00 

— 

5 

27 

At  sea. 

-27 

56 

312 

42 

Feb.  1837. 

Du  Petit-Thouars. 

— 

4 

30 

+ 0 

23 

— 

4 

07 

At  sea. 

— 28 

41 

313 

39 

April  1836 

Vaillant. 

— 

4 

12 

+ 0 

30 

— 

3 

42 

At  sea. 

-27 

16 

313 

44 

June  1832. 

FitzRoy. 

— 

5 

10 

+ 1 

00 

— 

4 

10 

At  sea. 

-27 

14 

314 

10 

June  1832. 

FitzRoy. 

— 

4 

34 

+ 1 

00 

— 

3 

34 

At  sea. 

-26 

09 

314 

18 

Feb.  1837. 

Du  Petit-Thouars. 

— 

2 

44 

+ 0 

23 

— 

2 

21 

At  sea. 

— 28 

15 

314 

53 

May  1830. 

Erman. 

— 

4 

10 

+ 1 

16 

— 

2 

54 

At  sea. 

-26 

18 

315 

28 

May  1830. 

Erman. 

— 

3 

31 

+ 1 

16 

— 

2 

15 

At  sea. 

-26 

49 

315 

55 

April  1836. 

Vaillant. 

— 

3 

06 

-hO 

30 

— 

2 

36 

At  sea. 

-26 

33 

316 

12 

June  1832. 

FitzRoy. 

— 

3 

39 

+ 1 

03 

— 

2 

36 

At  sea. 

— 24 

12 

316 

23 

Feb.  1837. 

Du  Petit-Thouars. 

— 

2 

04 

+ 0 

23 

— 

1 

41 

At  sea. 

— 24 

12 

316 

36 

May  1830. 

Erman. 

— 

2 

10 

+ 1 

20 

— 

0 

50 

At  sea. 

— 23 

30 

316 

40 

Feb.  1837. 

Du  Petit-Thouars. 

__ 

2 

00 

+ 0 

23 

— 

1 

37 

At  sea. 

— 24 

43 

316 

47 

May  1830. 

Erman. 

— 

2 

41 

+ 1 

20 

— 

1 

21 

At  sea. 

— 23 

46 

316 

49 

.May  1832. 

Erman. 

— 

1 

30 

+ 1 

20 

— 

0 

10 

At  sea. 

— 23 

03 

316 

54 

June  1 832. 

FitzRoy. 

— 

1 

39 

+ 1 

03 

— 

0 

36 

At  sea. 

— 22 

55 

3l6 

55 

June  1832. 

FitzRoy. 

— 

2 

00 

+ 1 

03 

— 

0 

57 

Rio  de  Janeiro. 

—22 

54 

3l6 

55 

June  1830. 

Erman. 

— 

2 

08 

+ 1 

20 

— 

0 

48 

Rio  de  Janeiro. 

-22 

54 

316 

55 

April  1836. 

Vaillant. 

— 

0 

50 

+ 0 

31 

— 

0 

19 

Rio  de  Janeiro. 

— 22 

54 

316 

55 

Feb.  1837. 

Du  Petit-Thouars. 

— 

0 

51 

+0 

23 

— 

0 

28 

Rio  de  Janeiro. 

— 22 

54 

3l6 

55 

July  1845. 

Von  Helmriecher. 

— 

0 

13 

-0 

47 

— 

1 

00 

Rio  de  Janeiro. 

— 24 

06 

317 

07 

June  1832. 

FitzRoy. 

— 

1 

57 

+ 1 

03 

— 

0 

54 

At  sea. 

— 24 

00 

317 

09 

Feb.  1847. 

Stanley. 

— 

0 

47 

—1 

00 

— 

1 

47 

At  seaf. 

— 23 

09 

317 

17 

June  1 830. 

Erman. 

— 

1 

39 

+ 1 

20 

— 

0 

19 

At  sea. 

-24 

38 

317 

19 

Jan.  1844. 

Pasley. 

— 

1 

00 

-0 

34 

— 

1 

34 

At  sea. 

— 25 

23 

317 

37 

April  1836. 

Vaillant. 

— 

1 

09 

+ 0 

32 

— 

0 

37 

At  sea. 

-23 

00 

318 

03 

July  1828. 

Foster. 

— 

1 

07 

+1 

40 

+ 

0 

33 

Cape  Frio. 

— 24  07 

318 

07 

April  1836. 

Vaillant. 

— 

0 

30 

+ 0 

32 

+ 

0 

02 

At  sea. 

-23 

05 

318 

10 

April  1836. 

Vaillant. 

— 

2 

30 

+ 0 

32 

— 

1 

58 

At  sea. 

-29 

17 

318 

13 

Dec.  1843. 

Pasley. 

0 

00 

— 0 

34 

— 

0 

34 

At  sea. 

-23 

30 

318 

13 

June  1830. 

Erman. 

— 

1 

03 

+ 1 

20 

+ 

0 

17 

At  sea. 

-27 

11 

318 

38 

Jan.  1844. 

Pasley. 

0 

00 

-0 

34 

— 

0 

34 

At  sea. 

— 24 

56 

318 

38 

April  1836. 

Vaillant. 

— 

0 

23 

+ 0 

34 

+ 

0 

11 

At  sea. 

— 22 

58 

318 

45 

June  1832. 

FitzRoy. 

— 

0 

24 

+ 1 

07 

0 

43 

At  sea. 

— 22 

53 

319 

18 

Feb.  1837. 

Du  Petit-Thouars. 

+ 

2 

12 

+ 0 

26 

2 

38 

At  sea. 

— 25 

59 

319 

19 

Feb.  1847. 

Stanley. 

1 

33 

-1 

04 

0 

29 

At  seaf. 

—22 

42 

319 

39 

June  1832. 

FitzRoy. 

0 

03 

-fl 

10 

1 

13 

At  sea. 

— 24 

48 

320 

23 

June  1830. 

Erman. 

1 

03 

+ 1 

30 

2 

33 

At  sea. 

-20 

50 

320 

32 

Dec.  1843. 

Pasley. 

3 

00 

-0 

38 

2 

22 

At  sea. 

— 22  07 

320 

39 

Jan.  1847. 

Stanley. 

3 

01 

— 1 

06 

1 

55 

At  seaf. 

—20 

12 

322 

06 

Jan.  1847. 

Stanley. 

5 

05 

-1 

06 

3 

59 

At  seaf. 

-27  52 

322 

42 

Jan.  1847. 

Stanley. 

2 

20 

-1 

06 

1 

14 

At  seaf. 

— 24 

52 

323 

43 

June  1830. 

Erman. 

2 

20 

+1 

30 

3 

50 

At  sea. 

—20 

38 

324 

44 

June  1830. 

Erman. 

3 

32 

+1 

30 

5 

02 

At  sea. 

—22 

28 

324 

46 

June  1830. 

Erman. 

3 

33 

+ 1 

30 

5 

03 

At  sea. 

— 22 

39 

324 

59 

Oct.  1842. 

Berard. 

3 

30 

— 0 

26 

3 

04 

At  sea. 

— 24 

03 

325 

08 

June  1830. 

Erman. 

3 

12 

+ 1 

35 

4 

47 

At  sea. 

-25 

00 

325 

16 

June  1830. 

Erman. 

2 

45 

+1 

35 

4 

20 

At  sea. 

-25 

09 

327 

42 

Oct.  1842. 

Berard. 

5 

00 

— 0 

26 

4 

34 

At  sea. 

—26 

58 

329 

17 

Oct.  1842. 

Berard. 

4 

15 

— 0 

27 

3 

48 

At  sea. 

-20 

30 

330 

37 

Dec.  1839. 

Ross. 

8 

01 

0 

00 

8 

01 

At  seaf. 

— 21 

30 

330 

46 

Dec.  1839. 

Ross. 

9 

43 

0 

00 

9 

43 

At  seaf. 

-22 

40 

330 

52 

Dec.  1839. 

Ross. 

9 

01 

0 

00 

9 

01 

At  seaf. 

— 23 

19 

330 

56 

Dec.  1839. 

Ross. 

7 

45 

0 

00 

7 

45 

At  seaf. 

2 G 2 


224 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

20°  and 

— 30°  (continued). 

0 

— 27 

/ 

42 

331 

10 

Nov.  1842. 

Berard. 

O 

6 

/ 

15 

-0 

27 

O 

5 

48 

At  sea. 

-24 

42 

332 

05 

Dec.  1839. 

Ross. 

7 

08 

0 

00 

7 

08 

At  seaf. 

— 26 

58 

333 

24 

Dec.  1839. 

Ross. 

9 

24 

0 

00 

9 

24 

At  seaf. 

—26 

37 

333 

26 

Dec.  1839. 

Ross. 

8 

02 

0 

00 

8 

02 

At  seaf. 

-27 

04 

334 

14 

Dec.  1839. 

Ro.ss. 

10 

04 

0 

00 

10 

04 

At  seaf. 

-27 

40 

335 

06 

Dec.  1839. 

Ross. 

9 

37 

0 

00 

9 

37 

At  seaf. 

-25 

30 

335 

20 

Dec.  1839. 

Ross. 

10 

35 

0 

00 

10 

35 

At  seaf. 

—26 

55 

335 

21 

Dec.  1839. 

Ross. 

9 

48 

0 

00 

9 

48 

At  seaf. 

-25 

45 

335 

43 

Dec.  1839. 

Ross. 

10 

22 

0 

00 

10 

22 

At  seaf. 

—26 

51 

337 

11 

Dec.  1839. 

Ross. 

11 

10 

0 

00 

11 

10 

At  seaf. 

-27 

44 

338 

36 

Dec.  1839. 

Ross. 

12 

00 

0 

00 

12 

00 

At  seaf. 

— 28 

15 

340 

08 

Jan.  1840. 

Ross. 

13 

23 

0 

00 

13 

23 

At  seaf. 

-27 

55 

341 

50 

Jan,  1840. 

Ross. 

13 

13 

0 

00 

13 

13 

At  seaf. 

-27 

33 

342 

27 

Jan.  1840. 

Ross. 

'13 

41 

0 

00 

13 

41 

At  seaf. 

-25 

48 

342 

55 

Jan.  1840. 

Ross. 

14 

11 

0 

00 

14 

11 

At  seaf. 

— 24 

39 

343 

02 

Jan.  1840. 

Ross. 

14 

26 

0 

00 

14 

26 

At  seaf. 

-22 

54 

343 

36 

Jan.  1840. 

Ross. 

14 

59 

0 

00 

14 

59 

At  seaf. 

—20 

20 

345 

07 

Jan.  1840. 

Ross. 

17 

50 

0 

00 

17 

50 

At  seaf. 

—29 

56 

345 

54 

June  1846. 

Berard. 

17 

48 

— 1 

14 

16 

34 

At  sea. 

-27 

00 

346 

33 

Jan.  1840. 

Ross. 

17 

53 

0 

00 

17 

53 

At  seaf. 

-27 

53 

346 

43 

Jan.  1840. 

Ross. 

18 

30 

0 

00 

18 

30 

At  seaf. 

— 26 

10 

347 

18 

Jan.  1840. 

Ross. 

17 

51 

0 

00 

17 

51 

At  seaf. 

-25 

23 

347 

49 

Jan.  1840. 

Ross. 

19 

55 

0 

00 

19 

55 

At  seaf. 

-28 

48 

348 

14 

Jan.  1840. 

Ross. 

18 

19 

0 

00 

18 

19 

At  seaf. 

— 24 

41 

348 

39 

Jan.  1840. 

Ross. 

20 

21 

0 

00 

20 

21 

At  seaf. 

— 28 

05 

349 

16 

June  1846. 

Berard. 

19 

56 

— 1 

14 

18 

42 

At  sea.  ■ 

-29 

58 

350 

52 

Jan.  1840. 

Ross. 

19 

55 

0 

00 

19 

55 

At  seaf. 

-23 

32 

351 

04 

Feb.  1840. 

Ross. 

21 

39 

0 

00 

21 

39 

At  seaf. 

— 22 

00 

351 

19 

Feb.  1840. 

Ross. 

22 

17 

0 

00 

22 

17 

At  seaf. 

— 20 

15 

352 

04 

Feb.  1840. 

Ross. 

23 

12 

0 

00 

23 

12 

At  seaf. 

— 20 

51 

2 

38 

May  1839. 

Du  Petit- Thouars. 

25 

27 

+ 0 

05 

25 

32 

At  sea. 

-22 

17 

4 

36 

June  1836. 

FitzRoy. 

24 

12 

+ 0 

24 

24 

36 

At  sea. 

— 22 

56 

5 

06 

June  1836. 

FitzRoy. 

24 

09 

+ 0 

24 

24 

33 

At  sea. 

— 25 

54 

7 

28 

April  1839. 

Du  Petit-Thouars. 

26 

28 

+ 0 

05 

26 

33 

At  sea. 

— 26 

35 

7 

33 

April  1839. 

Du  Petit-Thouars. 

26 

28 

+ 0 

05 

26 

33 

At  sea. 

-27 

35 

8 

05 

Aug.  1842. 

Jehenne. 

28 

00 

-0 

18 

27 

42  At  sea. 

-27 

23 

8 

32 

April  1839. 

Du  Petit-Thouars. 

27 

08 

+ 0 

05 

27 

13  At  sea. 

-27 

48 

9 

50 

Aug.  1837. 

Vaillant. 

26 

06 

+ 0 

18 

26 

24! At  sea. 

— 24 

31 

10 

35 

Aug.  1837. 

Vaillant. 

25 

11 

+ 0 

18 

25 

29  At  sea. 

-29 

33 

10 

58 

April  1839. 

Du  Petit-Thouars. 

26 

51 

+ 0 

05 

26 

56  At  sea. 

—29 

12 

01 

Aug.  1837. 

Vaillant. 

26 

02 

+ 0 

18 

26 

20  At  sea. 

Between  the  latitudes  of  —30°  and  — 

40°. 

-38 

44 

297 

45 

1833. 

FitzRoy. 

— 15 

20 

+ 0 

16 

-15 

04 

Argentine  Fort. 

-39 

58 

297 

53 

1833. 

FitzRoy. 

— 15 

50 

+ 0 

16 

— 15 

34 

Indian  Head. 

-39 

52 

297 

54 

1833. 

FitzRoy. 

— 15 

40 

+ 0 

16 

— 15 

24 

Colorado  River. 

-39 

27 

297 

57 

1833. 

FitzRoy. 

— 15 

30 

+ 0 

16 

— 15 

14 

Labyrinth  Head. 

-39 

16 

298 

00 

1833. 

FitzRoy. 

— 15 

20 

+ 0 

16 

-15 

04 

Ariadne  Island. 

-38 

57 

298 

01 

1833. 

FitzRoy. 

-15 

00 

+ 0 

19 

-14 

41 

Point  Johnson. 

-39 

1 1 

298 

06 

1833. 

FitzRoy. 

— 15 

10 

+ 0 

19 

— 14 

51 

Zuraita  Island. 

— 38 

59 

298 

20 

1833. 

FitzRoy. 

-14 

50 

+ 0 

19 

— 14 

31 

Mount  Hermoso. 

— 38 

57 

298 

42 

Aug.  1833.  FitzRoy. 

-15 

10 

+ 0 

20 

-14 

50 

At  sea. 

-39 

10 

299 

19 

Aug.  1833.  FitzRoy. 

*-15 

07 

+ 0 

26 

— 14 

41 

At  sea. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


225 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

-30 

° and  —40°  (continued). 

0 

-31 

41 

299 

34 

jjan.  1846. 

Sulivan. 

O 

— 13 

/ 

14 

0 

-0 

24 

O 

— 13 

38 

Bahada  de  Santa  Fe. 

—38  39 

301 

12 

1833. 

FitzRoy. 

— 14 

00 

+ 0 

26 

— 13 

34 

Black  Point. 

-34 

36 

301 

38 

1833. 

FitzRoy. 

— 11 

40 

+ 0 

26 

— 11 

14 

Buenos  Ayres. 

-33 

41 

301 

53 

Sept.  1845. 

Sulivan. 

— 12 

06 

-0 

23 

— 12 

29 

River  Uruquay. 

—32 

20 

301 

55 

Sept.  1845. 

Sulivan. 

— 11 

14i  -0 

23 

-11 

37 

Sandy  Island. 

-34 

28 

302 

11 

Aug.  1844. 

Sulivan. 

- 11 

36 

1-0 

18 

— 11 

54 

Colon!  a. 

-38 

17 

302 

21 

1833. 

FitzRoy. 

— 14 

00 

+ 0 

28 

-13 

32 

Point  San  Andres. 

-34 

42 

302 

28 

Nov.  1832. 

FitzRoy. 

-11 

33 

+ 0 

32 

— 11 

01 

At  sea. 

-38 

06 

302 

31 

1833. 

FitzRoy. 

-13 

50 

+ 0 

29 

-13 

21 

Cape  Corientes. 

-35 

43 

302 

41 

1833. 

FitzRoy. 

— 12 

30 

+ 0 

29 

-12 

01 

Rio  Salado. 

-35 

42 

302 

42 

1833. 

FitzRoy. 

-12 

30 

+ 0 

29 

-12 

01 

River  Sanborombon. 

— 35 

27 

302 

55 

1833. 

FitzRoy. 

-12 

30 

+ 0 

29 

-12 

01 

Point  Piedras. 

-34 

41 

303 

12 

Aug.  1832. 

FitzRoy. 

— 11 

49 

+ 0 

34 

— 11 

15 

At  sea. 

-36 

19 

303 

14 

1833. 

FitzRoy. 

— 13 

00 

+ 0 

29 

— 12 

31 

Cape  San  Antonio. 

-39 

69 

303 

19 

1833. 

FitzRoy. 

-13 

30 

+ 0 

29 

-13 

01 

Medanos  Point. 

-36 

56 

303 

25 

Aug.  1 832. 

FitzRoy. 

-12 

36 

+ 0 

34 

— 12 

02 

At  sea. 

-34 

52 

303 

36 

Aug.  1833. 

FitzRoy. 

-11 

46 

+ 0 

29 

— 12 

15 

At  sea. 

-34 

57 

303 

42 

Nov.  1832. 

FitzRoy. 

-12 

28 

+ 0 

34 

— 11 

54 

At  sea. 

-34 

53 

303 

47 

1833. 

FitzRoy. 

-12 

40 

+ 0 

29 

-12 

11 

Monte  Video. 

-34 

53 

303 

47 

April  1836. 

Vaillant. 

— 10 

35 

+ 0 

17 

— 10 

18 

Monte  Video. 

-34 

54 

303 

48 

July  1843. 

Sulivan. 

-10 

42 

-0 

16 

-10 

58 

Monte  Video. 

— 34 

54 

303 

48 

Aug.  1844. 

Sulivan. 

-10 

53 

-0 

20 

— 11 

13 

Monte  Video. 

-34 

37 

305 

02 

1833. 

FitzRoy. 

-12 

28 

+ 0 

32 

— 11 

56 

Gorriti. 

-35 

14 

305 

14 

April  1836. 

Vaillant. 

-10 

57 

+ 0 

20 

-10 

37 

At  sea. 

-38 

37 

305 

46 

Feb.  1837. 

Du  Petit-Thouars. 

-10 

34 

+ 0 

16 

-10 

18 

At  sea. 

-35 

52 

306 

16 

April  1836. 

Vaillant. 

- 8 

40 

+ 0 

20 

— 8 

20 

At  sea. 

-34 

05 

306 

49 

April  1836. 

Vaillant. 

- 8 

25 

+ 0 

20 

- 8 

05 

At  sea. 

-35 

01 

306 

52 

April  1836. 

Vaillant. 

-10 

14 

fO 

20 

- 9 

54 

At  sea. 

— 34  57 

307 

31 

April  1836. 

Vaillant. 

- 9 

10 

+ 0 

20 

- 8 

50 

At  sea. 

-34  09 

307 

57 

July  1832. 

FitzRoy. 

— 10 

27 

4-0 

45 

- 9 

42 

At  sea. 

-34 

16 

308 

20 

Feb.  1837. 

Du  Petit-Thouars. 

- 7 

28 

+ 0 

17 

- 7 

11 

At  sea. 

-39 

49 

308 

53 

April  1830. 

Erman. 

— 11 

44 

+ 0 

57 

— 10 

47 

At  sea. 

-33 

16 

309 

27 

April  1836. 

Vaillant. 

- 8 

18 

+ 0 

22 

- 7 

56 

At  sea. 

-38 

29 

309 

31 

April  1830. 

Erman. 

— 11 

16 

+ 0 

57 

— 10 

19 

At  sea. 

-33 

42 

309 

40 

April  1 836. 

Vaillant. 

_ 6 

56 

+ 0 

22 

- 6 

34 

At  sea. 

— 32 

37 

309 

43 

Aug.  1837. 

Du  Petit-Thouars. 

— 5 

37 

+ 0 

17 

- 5 

20 

At  sea. 

-38 

13 

309 

45 

April  1 830. 

Erman. 

-10 

10 

+ 1 

06 

- 9 

04 

At  sea. 

-37 

15 

310 

00 

April  1830. 

Erman. 

- 9 

25 

+ 1 

06 

— 8 

19 

At  sea. 

-35  47 

310 

33 

April  1830. 

Erman. 

- 8 

19 

+ 1 

06 

- 7 

13 

At  sea. 

-34 

49 

310 

55 

April  1830. 

Erman. 

- 8 

08 

+ 1 

06 

- 7 

02 

At  sea. 

-31 

09 

311 

03 

July  1832. 

FitzRoy. 

- 7 

50 

+ 0 

53 

- 6 

57 

At  sea. 

— 30 

56 

311 

44 

April  1836. 

Vaillant. 

— 4 

44 

+ 0 

26 

— 4 

18 

At  sea. 

— 32 

38 

312 

27 

1830. 

Erman. 

- 7 

17 

-f  1 

10 

- 6 

07 

At  sea. 

— 30 

51 

313 

22 

May  1830. 

Erman. 

— 5 

13 

+ 1 

10 

- 4 

03 

At  sea. 

-30 

23 

316 

15 

April  1 846. 

Sulivan. 

— 4 

15 

— 1 

00 

— 5 

15 

At  seaf. 

-30 

12 

318 

18 

Dec.  1843. 

Pasley. 

0 

00 

-0 

35 

— 0 

35 

At  sea. 

-31 

55 

318 

30 

Jan.  1844. 

Pasley. 

0 

00 

-0 

35 

— 0 

35 

At  sea. 

-30 

06 

318 

45 

Aprill846 

Sulivan. 

- 2 

10 

— 1 

00 

— 3 

10 

At  seaf-. 

-31 

26 

320 

34 

Jan.  1844. 

Pasley. 

+ 1 

20 

-0 

36 

+ 0 

44 

At  sea. 

-30 

22 

321 

00 

Jan.  1844. 

Pasley. 

+ 1 

00 

-0 

36 

0 

24 

At  sea. 

-31 

20 

322 

06 

Jan.  1844. 

Pasley. 

+ 1 

17 

-0 

36 

0 

43 

At  sea. 

-33 

13 

323 

09 

Feb.  1847. 

Stanley. 

+ 2 

48 

— 1 

12 

1 

36 

At  seaf. 

-30 

50 

323 

14 

Feb.  1847. 

Stanley. 

+ 2 

24 

— 1 

12 

1 

12 

At  seat. 

-35 

07 

324 

14 

Feb.  1847. 

Stanley. 

+ 2 

49 

— 1 

19 

1 

30 

At  seat- 

-36 

37 

326 

57 

Feb.  1847. 

Stanley. 

+ 2 

37 

— 1 

24 

1 

13 

At  seat- 

-37 

24 

328 

42 

Feb.  1847. 

Stanley. 

+ 4 

09 

— 1 

25 

2 

44 

At  seat- 

226 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XIL  (Continued.) 


Lat. 

Long. 

nate. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

30 

^ and 

— 40°  (continued). 

-36 

50 

332 

01 

Feb.  1847. 

Stanley. 

6 

32 

O 

— 1 

26 

O 

5 

06 

At  seaf. 

-36 

32 

333 

25 

Feb.  1847. 

Stanley. 

7 

51 

— 1 

26 

6 

25 

At  seaf. 

-31 

01 

335 

28 

Nov.  1842. 

Berard. 

11 

30 

— 0 

32 

10 

58 

At  sea. 

-36 

42 

336 

14 

May  1846. 

Berard. 

7 

54 

—1 

14 

6 

40 

At  sea. 

-36 

31 

336 

28 

Feb.  1847. 

Stanley. 

10 

00 

— 1 

26 

8 

34 

At  seat* 

-31 

49 

337 

53 

Nov.  1842. 

Berard. 

13 

45 

-0 

34 

12 

41 

At  sea. 

-38 

26 

336 

42 

May  1846. 

Berard. 

7 

45 

— 1 

18 

6 

27 

At  sea. 

— 35 

18 

337 

23 

May  1846. 

Berard. 

11 

03 

— 1 

14 

9 

49 

At  sea. 

-33 

26 

339 

58 

May  1846. 

Berard. 

12 

44 

— 1 

14 

11 

30 

At  sea. 

-35 

31 

340 

26 

Feb.  1847. 

Stanley. 

13 

07 

— 1 

26 

11 

41 

At  seaf. 

-37 

01 

341 

09 

Feb.  1847. 

Stanley. 

11 

13 

— 1 

26 

9 

47 

At  seaf. 

-36 

52 

341 

31 

Feb.  1847. 

Stanley. 

11 

58 

— 1 

26 

10 

32 

At  seaf. 

— 32 

14 

342 

11 

June  1846. 

Berard. 

.13 

36 

— 1 

14 

12 

22 

At  sea. 

-38 

02 

343 

00 

Feb.  1847. 

Stanley. 

13 

07 

— 1 

22 

12 

45 

At  seat* 

-30 

41 

344 

38 

June  1846. 

Berard. 

17 

16 

— 1 

11 

16 

05 

At  sea. 

-37 

57 

349 

19 

Feb.  1847. 

Stanley. 

14 

30 

—1 

20 

13 

10 

At  seaf. 

-34 

31 

350 

21 

Nov,  1842. 

Berard. 

16 

00 

-0 

32 

15 

28 

At  sea. 

-37 

27 

352 

40 

Feb.  1847. 

Stanley. 

18 

40 

— 1 

20 

17 

20 

At  seaf. 

-30 

58 

353 

26 

Feb.  1840. 

Ross. 

21 

48 

-0 

02 

21 

46 

At  seaf. 

-36 

05 

355 

10 

Feb.  1847. 

Stanley. 

20 

02 

— 1 

16 

18 

46 

At  seaf. 

-31 

32 

355 

37 

Feb.  1840. 

Ross. 

21 

54 

-0 

02 

21 

52 

At  seaf. 

-34 

45 

355 

39 

Feb.  1847. 

Stanley. 

21 

43 

— 1 

16 

20 

27 

At  seaf. 

— 35 

23 

356 

39 

Feb.  1847. 

Stanley. 

23 

08 

— 1 

16 

21 

52 

At  seat* 

-35 

30 

357 

00 

Feb.  1847. 

Stanley. 

22 

41 

— 1 

16 

21 

25 

At  seat* 

— 35 

42 

357 

09 

Nov.  1842. 

Berard. 

21 

00 

— 0 

29 

20 

31 

At  sea. 

-36 

58 

358 

28 

Feb.  1847. 

Stanley. 

22 

16 

— 1 

12 

21 

04 

At  seat* 

-31 

01 

359 

26 

Feb.  1840. 

Ross. 

23 

29 

0 

00 

23 

29 

At  seat* 

-31 

13 

359 

31 

Feb.  1840. 

Ross. 

23 

02 

0 

00 

23 

02 

At  seat* 

-30 

30 

359 

36 

Feb.  1840. 

Ross. 

23 

08 

0 

00 

23 

08 

At  seat* 

-38 

23 

359 

37 

Feb.  1847. 

Stanley. 

22 

28 

— 1 

04 

21 

24 

At  seat* 

-31 

28 

359 

38 

Feb.  1840. 

Ross. 

23 

41 

0 

00 

23 

41 

At  seat* 

-31 

19 

359 

46 

Feb.  1840. 

Ross. 

23 

08 

0 

00 

23 

08 

At  seat* 

— 30 

37 

359 

48 

Feb.  1840. 

Ross. 

23 

33 

0 

00 

23 

33 

At  seat* 

-38 

52 

1 

01 

Feb.  1847. 

Stanley. 

23 

41 

— 1 

04 

22 

37 

At  seat* 

-32 

00 

1 

48 

Feb.  1840. 

Ross. 

24 

07 

-0 

02 

24 

05 

At  seat* 

-32 

41 

4 

24 

Feb.  1840. 

Ross. 

24 

49 

— 0 

02 

24 

47 

At  seat* 

-38 

19 

4 

37 

Mar.  1847. 

Stanley. 

24 

30 

-1 

04 

23 

26 

At  seat* 

-33 

14 

6 

03 

Mar.  1840 

Ross. 

26 

48 

-0 

02 

26 

46 

At  seat* 

-33 

29 

7 

48 

Mar.  1840. 

Ross. 

27 

13 

-0 

02 

27 

11 

At  seat* 

— 33 

27 

9 

06 

Mar.  1840. 

Ross. 

28 

27 

— 0 

02 

28 

25 

At  seat* 

- 37 

10 

9 

28 

Mar.  1847. 

Stanley. 

27 

12 

— 0 

59 

26 

13 

At  seat* 

-33 

01 

9 

52 

Mar.  1840. 

Ross. 

28 

21 

-0 

02 

28 

19 

At  seat* 

— 38 

11 

10 

08 

Nov.  1842. 

Berard. 

26 

00 

-0 

21 

25 

39 

At  sea. 

-33 

14 

10 

37 

Mar.  1840. 

Ross. 

29 

22 

— 0 

02 

29 

20 

At  seat* 

-30 

02 

11 

38 

Aprill839. 

Du  Petit-Thouars. 

26 

21 

+ 0 

06 

26 

27 

At  sea. 

—36 

40 

12 

05 

Mar.  1847. 

Stanley. 

27 

50 

— 0 

52 

26 

58 

At  seat* 

-31 

25 

13 

22 

Aprill839. 

Du  Petit-Thouars. 

27 

19 

+ 0 

05 

27 

24 

At  sea. 

-35 

10 

13 

25 

Jan.  1845. 

Moore  and  Clerk. 

25 

10 

— 0 

35 

25 

05 

At  seat* 

-33 

00 

13 

36 

Mar.  1840. 

Ross. 

28 

44 

-0 

02 

28 

42 

At  seat* 

-36 

20 

13 

48 

Mar,  1847. 

Stanley. 

28 

27 

— 0 

48 

27 

39 

At  seat* 

— 35 

17 

14 

00 

Jan.  1845. 

Moore  and  Clerk. 

27 

15 

— 0 

20 

26 

45 

At  seat* 

-30 

40 

14 

09 

Aug.  1837. 

Vaillant. 

28 

35 

+ 0 

17 

28 

52 

At  sea. 

-32 

53 

14 

21 

Mar.  1840. 

Ross. 

29 

36 

-0 

02 

29 

34 

At  seat* 

-38 

43 

14 

25 

Jan.  1845, 

Moore  and  Clerk. 

25 

09 

-0 

30 

24 

39 

At  seat* 

-39 

18 

14 

28 

Jan.  1845. 

Moore  and  Clerk. 

28 

20 

-0 

30 

27 

50 

At  seat* 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


227 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

-30 

° and 

— 40°  (continued). 

-35 

26 

O 

15 

08 

Jan.  1845, 

Moore  and  Clerk. 

28 

39 

0 

— 0 

30 

28 

09 

At  seaf. 

— 32  57 

15 

27 

Aug.  1842. 

Jehenne. 

31 

16 

-0 

16 

31 

00 

At  sea. 

— 32 

23 

15 

52 

Mar.  1840. 

Ross. 

29 

23 

-0 

02 

29 

21 

At  seaf. 

— 33 

45 

15 

52 

Aug.  1837. 

Vaillant. 

28 

43 

-f-  0 

18 

29 

01 

At  sea. 

— 32 

03 

15 

53 

Aug.  1837. 

Vaillant. 

27 

16 

+ 0 

18 

27 

34 

At  sea. 

—33 

28 

15 

58 

April  1843. 

Du  Petit-Thouars. 

26 

37 

+ 0 

04 

26 

41 

At  sea. 

-39 

11 

15 

59 

Mar.  1843. 

Ross. 

28 

22 

-0 

21 

28 

01 

At  seaf. 

—39  52 

16 

04 

Mar.  1843. 

Crozier. 

26 

38 

-0 

21 

26 

17 

At  seaf. 

—35 

59 

16 

22 

Mar.  1 843. 

Crozier. 

27 

50 

-0 

21 

27 

29 

At  seaf. 

— 38 

26 

16 

39 

April  1843. 

Ross. 

29 

24 

-0 

21 

29 

03 

At  seaf. 

-35 

42 

16 

44 

April  1843. 

Crozier. 

27 

11 

-0 

21 

26 

50 

At  seaf. 

— 32  49 

16 

53 

Mar.  1840. 

Ross. 

29 

29 

-0 

02 

29 

27 

At  seaf. 

-32 

33 

16 

55 

Mar.  1840. 

Ross. 

29 

25 

-0 

02 

29 

23 

At  seaf. 

-33 

21 

17 

07 

Mar.  1840. 

Ross. 

29 

34 

-0 

02 

29 

32 

At  seaf. 

-32  59 

17 

08 

Mar.  1840. 

Ross. 

29 

46 

— 0 

02 

29 

44 

At  seaf. 

— 34 

42 

17 

36 

Jan.  1845. 

Moore  and  Clerk. 

29 

51 

— 0 

32 

29 

19 

At  seaf. 

— 34  37 

17 

51 

Mar.  1840. 

Ross. 

30 

10 

— 0 

02 

30 

08 

At  seaf. 

-34 

38 

17 

59 

Aprill839. 

Du  Petit-Thouars. 

27 

45 

+ 0 

04 

27 

49 

At  sea. 

— 34 

18 

18 

03 

Mar.  1840. 

Ross. 

29 

33 

-0 

02 

29 

31 

At  seaf. 

-34 

12 

18 

26 

1840. 

Ross. 

29 

04 

-0 

02 

29 

02 

At  seaf. 

— 34 

11 

18 

27 

April  1839. 

Du  Petit-Thouars. 

29 

09 

+ 0 

04 

29 

13 

False  ]3ay. 

— 33  56 

18 

29 

1841. 

Magnetic  Obseryy. 

29 

07 

0 

00 

29 

07 

Cape  of  Good  Hope. 

-34 

18 

18 

41 

Mar.  1830. 

Du  Petit-Thouars. 

29 

38 

+ 0 

04 

29 

42 

At  sea. 

Between  the  latitudes  of  —40°  and  — 

50*^ 

-49 

39 

292 

05 

Aprill834. 

FitzRoy. 

—20 

18 

+ 0 

14 

-20 

04 

At  sea. 

-49 

14 

292 

15 

1833. 

RitzRoy. 

—21 

10 

+ 0 

16 

— 20 

54 

Wood  Mount. 

-49 

15 

292 

18 

1833. 

FitzRoy. 

-21 

00 

+ 0 

16 

— 20 

44 

Sholl  Point. 

-49 

11 

292 

23 

1833. 

FitzRoy. 

—21 

00 

+ 0 

16 

-20 

44 

Port  San  Julian. 

-49 

14 

292 

24 

1833. 

FitzRoy. 

-21 

00 

+ 0 

16 

— 20 

44 

Desengano. 

—45 

57 

292 

26 

1 833. 

FitzRoy. 

-19 

42 

+0 

16 

-19 

26 

Point  Marques. 

— 48 

10 

292 

30 

Jan.  1834. 

FitzRoy. 

— 20 

50 

+0 

15 

— 20 

35 

At  sea. 

-46 

31 

292 

37 

1833. 

FitzRoy. 

-19 

40 

+ 0 

16 

-19 

24 

Murphy  Head. 

-45 

46 

292 

38 

1833. 

FitzRoy. 

-19 

40 

+ 0 

16 

-19 

24 

Cordova  Head. 

-48 

47 

292 

45 

Jan.  1834. 

FitzRoy. 

— 21 

28 

+ 0 

15 

-21 

13 

At  sea. 

-49 

10 

292 

45 

Jan.  1834. 

FitzRoy. 

-19 

47 

+ 0 

15 

-19 

32 

At  sea. 

-46 

41 

292 

50 

1833. 

FitzRoy. 

— 20 

00 

+ 0 

16 

-19 

44 

Bauza  Head. 

-48 

35 

293 

07 

1833. 

FitzRoy. 

—21 

00 

+ 0 

16 

-20 

44 

Lookout  Point. 

— 45 

10 

293 

28 

1833. 

FitzRoy. 

-19 

30 

+ 0 

16 

-19 

14 

Malaspina  Cove. 

-47 

49 

293 

37 

1833. 

FitzRoy. 

—20 

20 

+0 

16 

—20 

04 

Head  of  Port  Desire. 

-48 

21 

293 

39 

1833. 

FitzRoy. 

-20 

00 

+ 0 

16 

-19 

44 

Watchman  Cape. 

-48 

29 

293 

48 

1833. 

FitzRoy. 

— 21 

00 

+ 0 

16 

— 20 

44 

Bellaco  Rock. 

-48 

23 

293 

50 

Jan.  1834. 

FitzRoy. 

-19 

43 

+ 0 

15 

-19 

28 

At  sea. 

-47  45 

294 

00 

Jan.  1834. 

FitzRoy. 

-20 

30 

+ 0 

15 

— 20 

15 

At  sea. 

-48 

45 

294 

00 

Jan.  1834. 

FitzRoy. 

-18 

22 

+ 0 

15 

-18 

07 

At  sea. 

— 47  45 

294 

08 

Jan.  1834. 

FitzRov. 

-19 

57 

+ 0 

15 

-19 

42 

Port  Desire. 

-47 

06 

294 

09 

1833. 

FitzRoy. 

-19 

20 

+ 0 

17 

-19 

03 

Cape  Three  Points. 

-45 

04 

294 

12 

1833. 

FitzRoy. 

-19 

20 

+ 0 

17 

-19 

03 

Melo  Port. 

-47  57 

294 

14 

1833. 

FitzRoy. 

— 20 

50 

+ 0 

17 

— 20 

33 

Sea-Bear  Bay. 

-47 

12 

294 

17 

1833. 

FitzRoy. 

-19 

30 

+ 0 

17 

-19 

13 

Cape  Blanco. 

-45 

04 

294 

19 

1833. 

FitzRoy. 

-19 

00 

+ 0 

17 

-18 

43 

South  Cape. 

— 44 

56 

294 

28 

1833. 

FitzRoy. 

-19 

00 

+ 0 

17 

-18 

43 

Blanco  Islet. 

-44 

31 

294 

38 

1833. 

FitzRoy. 

-19 

08 

+ 0 

17 

-18 

51 

Santa  Elena. 

-43 

47 

294 

43 

1833. 

FitzRoy. 

-18 

30 

+ 0 

17 

-18 

13 

Lobos  Head. 

-49 

47 

294 

44 

April  1834. 

FitzRoy. 

— 22 

50 

+0 

15 

-22 

35|At  sea. 

228 


LINES  OF  MAGNETIC*  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

40 

^ and 

— 50°  (continued). 

O 

-44 

12 

294 

45 

1833. 

FitzRoY. 

0 

— 18 

50 

0 

+ 0 

17 

O 

-18 

33 

Atlas  Point. 

-47 

11 

294 

56 

Dec.  1833. 

FitzRoy. 

-19 

50 

+ 0 

16 

-19 

34 

Chupat  River. 

-43 

21 

294 

57 

April  1824. 

FitzRoy. 

-18 

06 

+ 0 

15 

- 17 

51 

At  sea. 

— 42  47 

295 

00 

1833. 

FitzRoy. 

-17 

50 

+ 0 

16 

-17 

34 

Western  Port. 

— 41 

40 

295 

06 

1833. 

FitzRoy. 

-17 

50 

+ 0 

16 

-17 

34 

Pozos  Point. 

-40 

49 

295 

06 

1833. 

FitzRoy. 

-17 

40 

+ 0 

16 

-17 

24 

Port  San  Antonio. 

— 42 

08 

295 

33 

April  1833. 

FitzRoy. 

-16 

53 

+ 0 

16 

-16 

37 

At  sea. 

-48 

46 

295 

36 

Jan.  1834. 

FitzRoy.  . 

-19 

18 

+ 0 

15 

-19 

03 

At  sea. 

— 42 

14 

295 

38 

1833. 

FitzRoy. 

-17 

45 

+ 0 

17 

-17 

28 

Entrance  Point. 

-42 

58 

295 

41 

1833. 

FitzRoy. 

-17 

50 

+ 0 

17 

-17 

33 

Point  Ninfas. 

-42 

35 

295 

42 

1833. 

FitzRoy. 

-17 

50 

+ 0 

17 

-17 

33 

Pyramid. 

— 42 

53 

295 

53 

1833. 

FitzRoy. 

— 17 

50 

+ 0 

17 

-17 

33 

Nuevo  Head. 

— 41 

09 

296 

05 

1833. 

FitzRoy. 

-17 

40 

+ 0 

17 

-17 

23 

Belen  BluH'. 

-42 

03 

296 

12 

1833. 

FitzRoy. 

-17 

50 

0 

17 

-17 

33 

Norte  Point. 

-42 

46 

296 

24 

1833. 

FitzRoy. 

-17 

50 

+ 0 

17 

-17 

33 

Delgado  Point. 

-42 

30 

296 

25 

1833. 

FitzRoy. 

-17 

50 

+ 0 

17 

-17 

33 

Valdes  Port. 

-40 

48 

297 

02 

18.33. 

FitzRoy. 

-17 

00 

+ 0 

17 

-16 

43 

Del  Carmen  Fort. 

— 41 

02 

297 

15 

1833. 

FitzRoy. 

-17 

40 

+ 0 

17 

-17 

23 

Negro  River. 

-45 

12 

297 

37 

Dec.  1832. 

FitzRoy. 

-17 

25 

+ 0 

24 

-17 

01 

At  sea. 

-40 

52 

297 

42 

1833. 

FitzRoy. 

-17 

00 

+ 0 

20 

-16 

40 

Raza  Point. 

-49 

29 

297 

45 

May  1836. 

Vaillant. 

-19 

36 

+ 0 

09 

-19 

27 

At  sea. 

-49 

39 

297 

48 

Mar.  1837. 

Du  Petit-Thouars. 

-17 

00 

+ 0 

07 

-16 

53 

At  sea. 

-40 

36 

297 

51 

1833. 

FitzRoy. 

-16 

30 

+ 0 

18 

-16 

12 

Rubia  Point. 

— 40 

46 

297 

54 

Dec.  1832. 

FitzRoy. 

-15 

26 

+ 0 

20 

-15 

06 

At  sea. 

-40  27 

298 

00 

Aug.  1833. 

FitzRoy. 

-16 

lb 

+ 0 

18 

— 15 

58 

At  sea. 

-40  27 

298 

06 

1833. 

FitzRoy. 

-16 

30 

+ 0 

18 

-16 

12 

Snake  Bank. 

— 45 

26 

298 

18 

May  1836. 

Vaillant. 

-16 

52 

+ 0 

12 

-16 

40 

At  sea. 

-40 

52 

298 

23 

Aug.  1833. 

FitzRoy. 

-16 

42 

+ 0 

18 

-16 

24 

At  sea. 

—47 

30 

298 

27 

May  1836. 

Vaillant. 

-16 

16 

+ 0 

12 

-16 

04 

At  sea. 

— 42 

16 

298 

28 

Dec.  1832. 

FitzRoy. 

-16 

12 

+ 0 

22 

— 15 

50 

At  sea. 

-43 

56 

298 

35 

Dec.  1832. 

FitzRov. 

-16 

40 

+ 0 

22 

-16 

18 

At  sea. 

-44 

30 

298 

42 

Dec.  1833. 

FitzRoy. 

-18 

14 

+ 0 

20 

-17 

54 

At  sea. 

-43 

14 

298 

43 

Dec.  1832. 

FitzRoy. 

-16 

20 

+ 0 

22 

— 15 

58 

At  sea. 

-41 

17 

298 

47 

Aug.  1833.‘FitzRoy. 

— 14 

23 

+ 0 

21 

— 14 

02 

At  sea. 

— 43 

30 

298 

58 

Mar.  1837.  Du  Betit-Tliouars. 

— 15 

42 

+ 0 

11 

— 15 

31 

At  sea. 

— 43  27 

300 

01 

Dec.  1833. 

FitzRoy. 

— 15 

46 

+ 0 

26 

— 15 

20 

At  sea. 

— 42 

44 

300 

29 

May  1836. 

Vaillant. 

— 14 

10 

+0 

15 

— 13 

55 

At  sea. 

— 42 

34 

301 

06 

Dec.  1833. 

FitzRoy. 

-16 

01 

+ 0 

30 

-15 

31 

At  sea. 

-43 

05 

302 

50 

Mar.  1837. 

Du  Petit-Thouars. 

— 14 

10 

+ 0 

14 

-13 

56 

At  sea. 

-40 

30 

303 

07 

May  1836. 

Vaillant. 

-10 

57 

+ 0 

18 

-10 

39 

At  sea. 

— 41 

36 

304 

55 

Mar.  1837. 

Du  Petit-Thouars. 

-14 

20 

+ 0 

14 

-14 

06 

At  sea. 

— 40 

24 

306 

42 

Feb.  1837. 

Du  Petit-Thouars. 

-12 

05 

+ 0 

14 

— 11 

51 

At  sea. 

— 41 

41 

306 

48 

Feb.  1837. 

Du  Petit-Thouars. 

-13 

12 

+ 0 

14 

-12 

58 

At  sea. 

-44 

04 

307 

25 

April  1830. 

Erraan. 

-13 

40 

+ 0 

49 

-12 

51 

At  sea. 

-48 

49 

10 

16 

Mar.  1843. 

Ross. 

+ 24 

32 

-0 

30 

+ 24 

02 

At  sea. 

— 48 

13 

10 

29 

Mar.  1843. 

Crozier. 

23 

5b 

-0 

30 

23 

26 

At  sea  f. 

-48 

27 

10 

51 

Jan.  1845. 

Moore  and  Clerk. 

24 

50 

-0 

47 

24 

03 

At  seat- 

— 44 

45 

13 

19 

Jan.  1845. 

Moore  and  Clerk. 

26 

34 

— 0 

47 

25 

47 

At  seat* 

-46 

24 

13 

34 

Jan.  1845. 

Moore  and  Clerk. 

25 

54 

-0 

47 

25 

07 

At  seaf. 

— 43 

36 

13 

47 

Mar.  1843. 

Crozier. 

26 

40 

-0 

30 

26 

10 

At  seat. 

-43 

28 

14 

32 

Mar.  1843. 

Ross. 

28 

18 

-0 

30 

27 

48 

At  seaf. 

— 40 

15 

14 

35 

Jan.  1845. 

Moore  and  Clerk. 

27 

40 

-0 

45 

26 

55 

At  seaf. 

— 41 

51 

15 

03 

Mar.  1843. 

Crozier. 

27 

05 

-0 

30 

26 

35 

At  seaf. 

— 41 

38 

15 

12 

Mar.  1843. 

Ross. 

28 

40 

-0 

30 

28 

10 

At  seaf. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


229 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitude 

s of  —50°  and  — 

60° 

• 

O 

— 53 

33 

287 

34 

1834. 

FitzRoy. 

O 

— 23 

35 

0 

+ 0 

03 

0 

-23 

32 

Crosstide  Cape. 

—53 

31 

287 

35 

1834. 

FitzRoy. 

— 24 

00 

+ 0 

03 

-23 

57 

St.  Jerome  Point. 

— 54 

35 

287 

38 

1834. 

FitzRoy. 

-25 

00 

+ 0 

03 

— 24 

57 

V\'est  Furies. 

— 53 

33 

287 

41 

1834. 

FitzRoy. 

— 24 

06 

+ 0 

03 

— 24 

03 

Bachelor  River. 

— 54 

24 

287 

42 

1834. 

FitzRoy. 

-24 

30 

+ 0 

03 

£4 

27 

North  Cove. 

— 54 

02 

287 

45 

1834. 

FitzRoy. 

— 24 

00 

+ 0 

03 

-23 

57 

Bowles  Island. 

-53 

11 

287 

47 

1834. 

FitzRoy. 

-23 

45 

+ 0 

03 

-23 

42 

Gidley  Islet. 

-54 

38 

287 

48 

1834. 

FitzRoy. 

— 25 

00 

+ 0 

03 

£4 

57 

East  Furies. 

-54 

34 

287 

48 

18.34. 

FitzRoy. 

— 25 

00 

+ 0 

03 

— 24 

57 

Tussuck  Rock. 

-54 

25 

287 

49 

1834. 

FitzRoy. 

— 24 

30 

+ 0 

03 

—24 

27 

Mount  Skyring. 

-54 

39 

287 

53 

1834. 

FitzRoy. 

04 

40 

+ 0 

03 

— 24 

37 

Cape  Schomburgk. 

— 54 

36 

287 

55 

1834. 

FitzRoy. 

— 24 

40 

+ 0 

03 

— 24 

37 

Astrea  Island. 

-53 

42 

287 

59 

1834. 

FitzRoy. 

-24 

04 

+ 0 

03 

-24 

01 

Gallant  Port. 

-54 

42 

288 

05 

1834. 

FitzRoy. 

— 24 

34 

+ 0 

04 

-24 

30 

Townshend  Harbour. 

-53 

05 

288 

07 

1834. 

FitzRoy. 

— 23 

56 

+ 0 

04 

— 23 

52 

Inglefield  Island. 

-53 

55 

288 

10 

1834. 

FitzRoy. 

— 23 

40 

+ 0 

04 

-23 

36  San  Antonio. 

-53 

49 

288 

21 

1834. 

FitzRoy. 

-23 

50 

+ 0 

04 

-23 

46  Cape  Holland. 

— 54 

46 

288 

23 

1834. 

FitzRoy. 

— 24 

30 

+ 0 

04 

£4 

26  Cape  Desolation. 

— 52 

39 

288 

29 

1834. 

FitzRoy. 

— 23 

00 

+ 0 

04 

— 22 

56< FitzRoy  Passage. 

— 52 

39 

288 

30 

1834. 

FitzRoy. 

— 23 

34 

+ 0 

04 

-23 

30  Bennett  Point. 

-54 

56 

288 

32 

1834. 

FitzRoy. 

— 24 

15 

+ 0 

04 

-24 

1 IjCastlereagh  Cape. 

-55 

03 

288 

37 

1834. 

FitzRoy. 

—24 

20 

4-0 

05 

—24 

15 

Nicholson  Rocks. 

-55 

47 

288 

41 

1834. 

FitzRoy. 

-24 

10 

+ 0 

05 

— 24 

05 

Catherine  Island. 

— 53 

54 

288 

42 

1834. 

FitzRoy. 

-23 

20 

+ 0 

05 

-23 

15 

Cape  Froward. 

— 54 

23 

288 

43 

1834. 

FitzRoy. 

— 23 

50 

+ 0 

05 

-23 

45 

King  Island. 

-54 

59 

288 

50 

1834. 

FitzRoy. 

-24 

16 

+ 0 

05 

— 24 

11 

Doris  Cove. 

-54 

24 

288 

52 

1834. 

FitzRoy. 

— 24 

57 

+ 0 

05 

— 24 

52 

Warping  Cove. 

— 55 

04 

288 

52 

1834. 

FitzRoy. 

— 24 

16 

+ 0 

05 

-24 

11 

Hat  Isle. 

— 54 

24 

288 

53 

1834. 

FitzRoy. 

— 24 

00 

+ 0 

05 

-23 

55 

Tarn  Cape. 

-57 

35 

288 

54 

Apr. 

1842. 

Crozier. 

—25 

16 

-0 

02 

— 25 

18 

At  seaf. 

-55 

08 

288 

58 

1834. 

FitzRoy. 

— 24 

15 

+ 0 

05 

—24 

10 

Treble  Island. 

-53 

47 

289 

02 

1834. 

FitzRoy. 

— 23 

40 

+ 0 

06 

-23 

34 

Cape  San  Isidore. 

-53 

21 

289 

02 

1834. 

FitzRoy. 

— 23 

26 

+ 0 

06 

— 23 

20 

Point  St.  Mary. 

-53 

38 

289 

02 

1834. 

FitzRoy. 

— 23 

40 

+ 0 

06 

-23 

34 

Port  Famine  Observatory. 

-53 

38 

289 

05 

1834. 

FitzRoy. 

— 23 

00 

+ 0 

06 

-22 

54 

Point  Santa  Anna. 

— 52 

55 

289 

12 

1834. 

FitzRoy. 

-23 

30 

+ 0 

06 

-23 

24 

Porpoise  Point. 

-52 

47 

289 

14 

1834. 

FitzRoy. 

— 23 

29 

+ 0 

06 

— 23 

23 

Packet  Harbour. 

-53 

44 

289 

17 

1834. 

FitzRoy. 

-23 

20 

4-0 

06 

— 23 

14 

Quoin  Head. 

— 52 

42 

289 

23 

1834. 

FitzRoy. 

— 23 

50 

+ 0 

06 

— 23 

44 

Oazy  Harbour. 

-52 

49 

289 

23 

1834. 

FitzRoy. 

— 23 

50 

+ 0 

06 

-23 

44 

Elizabeth  Island. 

-52 

50 

289 

25 

1834. 

FitzRoy. 

-23 

58 

+ 0 

06 

-23 

52 

Santa  Martha  Island. 

-54 

54 

289 

31 

1833. 

FitzRoy. 

— 24 

14 

+ 0 

06 

-24 

08 

Stewart  Harbour. 

— 53 

20 

289 

32 

1834. 

FitzRoy. 

-23 

00 

-fO 

06 

-22 

54 

Cape  Monmouth. 

-53 

01 

289 

33 

1834. 

FitzRoy. 

— 23 

00 

-fO 

06 

-22 

54 

Point  Gente  Grande. 

— 52 

56 

289 

37 

1834. 

FitzRoy. 

— 23 

20 

-fO 

06 

-23 

14 

Quarter-Master  Island. 

— 53 

27 

289 

47 

1834. 

FitzRoy. 

-23 

20 

+ 0 

06 

-23 

14 

Cape  Bongainville. 

— 52 

39 

289 

47 

June  1834. 

FitzRoy. 

-23 

30 

+ 0 

06 

-23 

24 

Gregory  Bay. 

-50 

11 

289 

50 

Apr. 

1834. 

FitzRoy. 

— 21 

00 

+ 0 

06 

— 20 

54 

Junction  of  Chalia  Stream  with 
Santa  Cruz. 

— 55 

22 

289 

51 

1834. 

FitzRoy. 

04 

10 

+ 0 

06 

— 24 

04 

Mary  Point. 

-52 

45 

289 

52 

Jan. 

1834. 

FitzRoy. 

-23 

38 

-1-0 

06 

-23 

32 

At  sea. 

— 00 

23 

290 

00 

1834. 

FitzRoy. 

— 24 

04 

+ i) 

06 

-23 

58 

March  Harbour.  | 

— 55 

27 

290 

12 

1834. 

FitzRoy. 

— 24 

00 

-hO 

06 

-23 

54 

Nativity  Cape.  j 

— 55 

24 

290 

15 

1834. 

FitzRoy. 

— 23 

50 

+ 0 

06 

— 23 

44 

Broken  Mount. 

— 52 

37 

290 

15 

Mar. 

1834. 

FitzRoy. 

22 

40 

-.0 

06 

— 22 

34 

St  Philip’s  Bay. 

j— 58 

58 

290 

19 

1837. 

Du  Petit-Thouars. 

— 25 

38 

-hO 

03 

-25 

35 

At  sea. 

2 H 


MDCCCXLIX. 


230 


LINES  OP  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 

-50 

°and 

— 60°  (continued). 

O 

-52 

27 

290 

32 

1834. 

FitzRoy. 

-22 

30 

0 

+ 0 

06 

0 

— 22 

24 

Orange  Cape. 

— 52 

15 

290 

36 

1834. 

FitzRoy. 

— 22 

40 

+ 0 

06 

-22 

34 

Magalhaens  Strait. 

— 55 

51 

290 

40 

1834. 

FitzRoy. 

— 24 

10 

+0 

06 

— 24 

04 

Ildefonso  Isles. 

— 53 

23 

290 

52 

Feb. 

1834. 

FitzRoy. 

— 24 

40 

+ 0 

10 

— 24 

30 

At  sea. 

-50 

56 

290 

54 

1834. 

FitzRoy. 

-21 

30 

+ 0 

11 

— 21 

19 

Coy  Inlet. 

-50 

51 

290 

55 

1834. 

Fitz  Roy. 

-21 

30 

+ 0 

11 

-21 

19 

Redondo  Cape. 

— 54 

26 

290 

57 

1834. 

FitzRoy. 

— 22 

50 

+ 0 

08 

-22 

42 

Admiralty  Sound. 

— 51 

33 

291 

01 

1834. 

FitzRoy. 

— 21 

47 

+ 0 

11 

— 21 

36 

Gallegos  River. 

-55 

36 

291 

02 

1834. 

FitzRoy. 

— 24 

00 

+ 0 

08 

— 23 

52 

Mount  Beaufoy. 

— 52 

26 

291 

03 

1833. 

FitzRoy. 

— 22 

30 

+ 0 

13 

-22 

17 

Magalhaens  Strait. 

— 51 

36 

291 

04 

Jan. 

1845. 

Sulivan. 

-21 

54 

— 0 

10 

22 

04 

Gallegos  River. 

— 52 

17 

291 

04 

Jan. 

1834. 

FitzRoy. 

-22 

40 

+ 0 

12 

—22 

28 

Cape  Possession. 

-51 

32 

291 

05 

1833. 

FitzRoy. 

-22 

00 

+ 0 

13 

— 21 

47 

Cape  Fairweather. 

— 56 

28 

291 

17 

Jan. 

1833. 

Fitz  Roy. 

— 24 

.40 

+ 0 

14 

-24 

26 

Diego  Ramirez  Isles,  N.  and  S. 

Rocks. 

-52 

31 

291 

18 

1833. 

FitzRoy. 

-21 

00 

+ 0 

13 

-20 

47 

Broken  Cliff  Peak. 

-50 

15 

291 

29 

1833. 

FitzRoy. 

-22 

00 

+ 0 

13 

-21 

47 

Magalhaens  Strait. 

-50 

08 

291 

33 

Apr. 

1834. 

FitzRoy. 

— 20 

54 

+ 0 

11 

-20 

43 

At  sea. 

-52 

24 

291 

35 

1833. 

FitzRoy. 

-22 

36 

+ 0 

13 

-22 

23 

Dungeness  Point. 

-50 

07 

291 

37 

1833. 

FitzRoy. 

— 20 

54 

+ 0 

13 

— 20 

41 

Keel  Point. 

— 52 

20 

291 

38 

May  1834. 

FitzRoy. 

-22 

30 

+ 0 

11 

— 22 

19 

Virgin’s  Cape. 

— 50 

09 

291 

40 

1833. 

FitzRoy. 

-22 

54 

+ 0 

13 

— 22 

41 

Entrance  Mount. 

— 55 

35 

291 

31 

Feb. 

1834. 

FitzRoy. 

-23 

50 

+ 0 

11 

-23 

39 

Middle  Cove  (Wollaston  Island). 

— 55 

01 

291 

46 

1 833. 

FitzRoy. 

-23 

40 

+ 0 

13 

-23 

27 

Murray  Narrow. 

-53 

19 

291 

50 

Feb. 

1834. 

FitzRoy. 

— 22 

40 

+ 0 

11 

— 22 

29 

Cape  San  Sebastian. 

-55 

05 

291 

53 

1833. 

FitzRoy. 

— 2.3 

45 

+ 0 

13 

-23 

32 

Button  Island. 

-55 

43 

291 

54 

1833. 

FitzRoy. 

-23 

56 

-fO 

13 

— 23 

43 

False  Cape  Horn. 

— 55 

16 

291 

54 

18.33. 

FitzRoy. 

-23 

40 

+ 0 

13 

-23 

27 

Cape  Webley. 

-52 

07 

291 

55 

Jan. 

1834. 

FitzRoy. 

-21 

40 

+ 0 

12 

-21 

28 

At  sea. 

-55 

24 

291 

56 

Feb. 

183.3. 

FitzRoy. 

-23 

50 

+ 0 

13 

-23 

37 

Pack  Saddle  Island. 

— 55 

31 

291 

57 

1833. 

FitzRoy. 

-23 

56 

+ 0 

13 

-23 

43 

Orange  Bay. 

-50 

05 

291 

57 

Apr. 

1834. 

FitzRoy. 

-20 

54 

+ 0 

11 

— 20 

43 

Port  Santa  Cruz. 

— 55 

40 

292 

01 

18.34. 

FitzRoy. 

-23 

30 

+ 0 

10 

— 23 

20 

Lort  Point. 

— 55 

19 

292 

03 

1834. 

FitzRoy. 

-23 

50 

+ 0 

10 

-23 

40 

Vauverlandt  Islet. 

-53 

40 

292 

04 

1834. 

FitzRcy. 

-22 

50 

+ 0 

10 

-22 

40 

Sunday  Cape. 

— 55 

50 

292 

06 

1834. 

FitzRoy. 

— 24 

20 

+ 0 

10 

— 24 

10 

West  Point. 

-53 

15 

292 

09 

Feb. 

1834. 

FitzRoy. 

— 24 

12 

+ 0 

10 

— 24 

02 

At  sea. 

— 55 

55 

292 

22 

Dec. 

1832. 

FitzRoy. 

-24 

30 

-pO 

15 

— 24 

15 

Cape  Spencer. 

-55 

51 

292 

26 

Oct. 

1842. 

Ross. 

— 23 

41 

-0 

05 

— 23 

46 

St.  Martin’s  Cove. 

— 55 

51'  292 

26 

Dec. 

1832. 

FitzRoy. 

-24 

23 

+ 0 

15 

-24 

08 

St.  Martin’s  Cove. 

-53 

51 

292 

27 

Dec. 

1832. 

FitzRoy. 

— 22 

00 

+ 0 

15 

— 21 

45 

Cape  Penas. 

— 52 

16!  292 

30 

May 

1834. 

FitzRoy. 

-22 

22 

+ 0 

10 

— 22 

12 

At  sea. 

-54 

54 

292 

32 

1834. 

FitzRoy. 

-23 

00 

-fO 

10 

— 22 

50 

Clay  Cliff  Narrow. 

— 55 

34  292 

40 

1834. 

FitzRoy. 

-23 

45 

+ 0 

10 

— 23 

35 

Cape  de  Roos. 

— 56 

00  292 

44 

Sept.  1842. 

Ross. 

-24 

38 

-0 

05 

-24 

43 

At  seat- 

— 55 

59 

292 

44 

1834. 

FitzRoy. 

-24 

00 

+ 0 

11 

— 23 

49 

Cape  Horn. 

— 54 

00 

292 

45 

Feb. 

1834. 

FitzRoy. 

— 23 

05 

-hO 

11 

-22 

54 

At  sea. 

—53 

18 

292 

45 

1834. 

FitzRoy. 

— 22 

00 

+ 0 

11 

— 21 

49 

— 52 

.39 

292 

46 

Dec. 

1832. 

FitzRoy. 

— 21 

31 

+ 0 

15 

— 21 

16 

— 56 

07 

292 

53 

Nov. 

1842. 

Crozier. 

-19 

58 

-0 

05 

— 20 

03 

At  seaf. 

— 55 

18 

292 

54 

Jan. 

1833. 

FitzRoys 

-23 

25 

+ 0 

16 

-23 

09 

Goree  Road. 

5 — 55 

05 

292 

39 

1834. 

FitzRoy. 

— 23 

20 

+ 0 

13 

-23 

07 

Cape  Rees. 

—55 

56 

293 

01 

1834. 

FitzRoy. 

-23 

30 

+ 0 

13 

— 23 

17 

Deceit  Islets. 

— 52 

06 

293 

02 

Dec. 

1832. 

FitzRoy. 

—21 

35 

+0 

16 

— 21 

16 

At  sea. 

-55 

23 

293 

04 

1834. 

FitzRoy. 

-23 

42 

+ 0 

14 

-23 

28 

Terhalten  Island. 

I-.7 

09 

293 

07 

.May 

1836. 

Vaillant. 

— 22 

35 

+ 0 

09 

— 22 

26 

At  sea. 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


231 


Table  XII.  (Continued.) 


I 

Observed 

Correc- 

Corrected 

Lat. 

Long. 

Date. 

Observer. 

Declina- 

tion  for 

Declina- 

Remarks. 

1 

tion. 

Epoc 

h. 

tion. 

Between  the  latitudes  of  — 

50 

^ and 

— 60°  (continued). 

O 

-55 

18 

293 

13 

1834. 

FitzRov. 

0 

-23 

40 

0 

+ 0 

/ 

14 

-23 

/ 

26  Lennox  Harbour. 

— 55 

48 

293 

15 

1834. 

FitzRoy. 

-23 

00 

+ 0 

14 

-22 

46  Barnevelt. 

-55 

17 

293 

24 

1834. 

FitzRoy. 

-23 

30 

+ 0 

14 

-23 

16  Fifty  Point. 

— 55 

48 

293 

37 

Feb.  1834. 

FitzRoy. 

-23 

31 

+0 

15 

— 23 

16  At  sea. 

— 54 

57 

294 

13 

1834. 

FitzRoy. 

-22 

50 

+ 0 

14 

-22 

36  Aguirre  Bay. 

— 50 

42 

294 

15 

Dec.  1832. 

FitzRoy. 

— 20 

41 

+ 0 

18 

— 20 

23|At  sea. 

— 56 

46 

294 

30 

Apr.  1842. 

Crozier. 

— 20 

26 

-0 

06 

— 20 

32lAt  sea+. 

— 56 

49 

294 

31 

May  1836. 

Vaillant. 

— 24 

11 

+ 0 

09 

— 24 

02 

At  sea. 

|Dec.l832 

1 FitzRoj’i 

-54  39 

294 

46 

I and 
LFeb.1834 

-22 

50 

+0 

19 

-22 

31 

Cape  San  Vicente. 

— 51 

18 

294 

46 

Dec.  1832. 

FitzRoy. 

— 20 

26 

+0 

19 

— 20 

07 

At  sea. 

-54 

48 

294 

46 

Dec.  1832. 

FitzRoy. 

-22 

48 

+ 0 

19 

— 22 

29 

Good  Success  Bay. 

— 54 

41 

294 

53 

1834. 

FitzRoy. 

-22 

50 

+ 0 

15 

-22 

35 

Cape  San  Diego. 

— 54 

48 

295 

15 

1834. 

FitzRoy. 

— 22 

00 

+ 0 

15 

— 21 

45 

Middle  Cape. 

— 54 

54 

295 

15 

1834. 

FitzRoy. 

—22 

40 

+ 0 

15 

— 22 

25 

Cape  St.  Bartholomew. 

“54 

53 

295 

18 

1828. 

Foster. 

— 20 

32 

+ 0 

32 

— 20 

00 

Franklin  Bay. 

— 54 

48 

295 

19 

1828. 

Foster. 

-23 

33 

+ 0 

32 

— 23 

01 

Crossley  Bay. 

— 55 

42 

295 

20 

Nov.  1842. 

Crozier. 

— 24 

19 

-0 

08 

— 24 

27 

At  seaf. 

— 55 

39 

295 

23 

Nov.  1842. 

Ross. 

— 23 

41 

-0 

08 

-23 

49 

.\t  seaf. 

— 54  47 

295 

27 

1828. 

Foster. 

-21 

13 

+ 0 

32 

— 20 

41 

Flinders  Bay. 

-53 

54 

295 

32 

Mar.  1837. 

Du  Petit-Thouars. 

— 20 

10 

+0 

07 

— 20 

03 

At  sea  (2). 

-54  49 

295 

38 

1828. 

Foster. 

— 21 

43 

+ 0 

32 

-21 

11 

Port  Parry. 

-54 

42 

295 

42 

1834. 

FitzRoy. 

-22 

30 

+ 0 

15 

— 22 

15 

Cape  Colnett. 

— 50 

15 

295 

45 

Apr.  1834. 

FitzRov. 

-19 

52 

+ 0 

15 

-19 

37 

At  sea. 

-54 

50 

295 

47 

1828. 

Foster. 

— 22 

26 

+ 0 

32 

-21 

54, Grant  Bay. 

-54  39 

295 

54 

1834. 

FitzRoy. 

— 22 

30 

+ 0 

15 

— 22 

15  New  Year  Islands. 

— 54 

46 

295 

57 

1834. 

FitzRoy. 

— 22 

30 

+ 0 

15 

-22 

15 

Port  Cook. 

— 54 

46 

295 

58 

1828. 

Foster. 

— 22 

15 

+ 0 

32 

—21 

43  Observatory. 

— 54 

43 

296 

17 

1828. 

Foster. 

— 22 

30 

+ 0 

32 

-21 

58  Cape  St.  John. 

—51 

57 

296 

36 

Mar.  1837. 

Du  Petit-Thouars. 

—20 

16 

+ 0 

07 

-20 

09!  At  sea. 

-55 

41 

296 

47 

Sept.  1842. 

Crozier. 

— 24 

12 

— 0 

07 

-24 

19  At  seaf. 

— 53 

47 

297 

01 

May  1836. 

Vaillant. 

-19 

56 

+ 0 

16 

-19 

46  At  sea. 

— 50 

56 

297 

04 

May  1836. 

Vaillant. 

—20 

38 

+ 0 

10 

— 20 

28  At  sea. 

— 50 

44 

297 

17 

Mar.  1837. 

Du  Petit-Thouars. 

-19 

28 

+ 0 

08 

-19 

20  At  sea. 

-51 

43 

298 

43 

1834. 

FitzRoy. 

-20 

18 

+ 0 

20 

-19 

58  Ship  Harbour,  Falklands. 

-51 

42 

298 

43 

Jan.  1845. 

Sulivan. 

-19 

29 

-0 

19 

-19 

48 

New  Island,  Falklands. 

-52 

0] 

299 

00 

Feb.  1845. 

Sulivaii. 

-19 

58 

-0 

19 

-20 

17 

Reef  Harbour. 

— 55 

29 

299 

03 

Oct  1842. 

Ross. 

— 24 

33 

-0 

11 

04 

44 

At  seaf. 

-55 

32 

299 

12 

Oct.  1842. 

Ross. 

— 21 

46 

-0 

11 

— 21 

57 

At  seaf. 

— 52 

12 

299 

18 

18.34. 

FitzRoy. 

-20 

24 

+ 0 

19 

-20 

05 

Stephen’s  Port,  Falklands. 

-51 

21 

299 

21 

Jan.  1844. 

Sulivan. 

-18 

29 

-0 

14 

-18 

43 

Hope  Harbour,  Falklands. 

-51 

32 

299 

31 

Nov.  1844. 

Sulivan. 

-19 

07 

— 0 

17 

-19 

24 

Whale  Cove. 

-52 

03 

299 

44 

1834. 

FitzRoy. 

-20 

00 

+ 0 

17 

-19 

43 

Port  Edgar. 

— 54 

32 

299 

53 

Oct.  1842. 

Crozier. 

-22 

30 

-0 

09 

-22 

39 

At  seaf. 

-51 

21 

299 

56 

1834. 

FitzRoy. 

-19 

35 

+ 0 

17 

-19 

18 

Port  Eginont,  Falklands, 

-51 

21 

299 

56 

Apr.  1844. 

Sulivan. 

— 18 

47 

-0 

14 

-19 

01 

At  seaf. 

— 54 

53 

299 

59 

Oct.  1842. 

Ross. 

-21 

19 

-0 

09 

-21 

28 

At  seaf. 

-52 

21 

300 

15 

Feb.  1844. 

Sulivan. 

-18 

35 

-0 

13 

-18 

48 

Owen  Road,  Falklands. 

— 55 

58 

300 

16 

Apr.  1830. 

Erman. 

-19 

41 

+ 0 

30 

-19 

11 

At  sea. 

— 55 

07 

300 

19 

Sept.  1842. 

Crozier. 

-21 

56 

-0 

09 

-22 

05 

At  seaf. 

— 51 

20 

300 

30 

Apr.  1844. 

Sulivan. 

-18 

20 

— 0 

15 

-18 

35 

Tamar  Harbour,  Falklands. 

-52 

09 

300 

35 

Feb.  1844. 

Sulivan. 

— 18 

18 

-0 

15 

-18 

33 

Bay  of  Islands. 

-52 

21 

300 

40 

1834. 

FitzRoy. 

-19 

50 

+ 0 

17 

-19 

33 

Bull  Road. 

-52 

22 

300 

41 

1834. 

FitzRoy. 

-19 

42 

+ 0 

17 

-19 

25 

Porpoise  Point. 

— 53 

04 

300 

51 

Nov.  1842. 

Ross. 

-19 

57 

-0 

09 

-20 

06 

At  seaf. 

2 H 2 


232 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


Table  XII.  (Continued.) 


Lat.  1 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 50° 

and  —60°  (continued). 

0 .1 
— 52  12 

300°  56 

1834. 

FitzRoy. 

-19  30 

o / 

+ 0 18 

-19  12 

Adventure  Sound. 

-51  33 

300  57 

Nov.  1 844. 

Sulivan. 

— 17  56 

-0  16 

— 18  12 

Port  San  Carlos,  Falklands. 

—52  16 

301  06 

Aprill842. 

Ross. 

-16  29 

-0  09 

-16  38 

At  sea. 

— 52  14 

301  09 

Aprill842. 

Crozier. 

-18  25 

-0  09 

— 18  36 

At  sea. 

— 54  43 

301  12 

Nov.  1842. 

Crozier. 

-21  29 

-0  09 

— 21  38 

At  sea. 

-52  01 

301  22 

Dec.  1843. 

Sulivan. 

-18  14 

-0  15 

-18  29 

Seal  Cove,  Falklands. 

— 51  48 

301  50 

July  1844. 

Sulivan. 

— 16  52 

— 0 18 

— 17  10 

Pleasant  Island. 

— 51  31 

301  51 

Mar.  1 843. 

Sulivan. 

-17  26 

— 0 13 

-17  39 

Port  Louis,  Old  Settlement. 

-51  31 

301  53 

Jan.  1844. 

Sulivan. 

-17  16 

-0  16 

— 17  32 

Port  Louis. 

— 51  22 

301  53 

Aug.  1842. 

Ross. 

-17  36 

— 0 10 

-17  46 

Port  Lotiis. 

-51  32 

301  53 

1834. 

FitzRoy. 

-19  00 

+ 0 21 

-18  39 

Port  Louis. 

-51  30 

302  06 

Mar.  1833. 

FitzRoy. 

-18  43 

+ 0 24 

-18  19 

At  sea. 

-51  35 

302  10 

1834. 

FitzRoy. 

-19  00 

+ 0 22 

— 18  38 

Berkeley  Sound,  Falklands. 

— 51  41 

302  10 

Nov.  1 844. 

Sulivan. 

-17*18 

-0  19 

-17  37 

Stanley  Harbour. 

-52  04 

302  47 

Dec.  1842. 

Ross. 

-17  49 

-0  11 

— 18  00 

At  seaf. 

-52  54 

302  57 

Sept.  1 842. 

Crozier. 

— 21  38 

— 0 11 

-21  49 

At  seat. 

— 52  46 

303  12 

Dec.  1842. 

Crozier. 

-19  18 

-0  11 

-19  29 

At  seat- 

— 52  50 

303  12 

Dec.  1842. 

R OSS. 

— 18  20 

-0  11 

— 18  31 

At  seat. 

— 56  53 

303  21 

May  1846. 

Berard. 

-18  16 

— 0 25 

— 18  31 

At  sea. 

— 55  05 

303  22 

Sept.  1830. 

Ernian. 

-18  58 

+ 0 30 

-18  28 

At  sea. 

-53  50 

303  49 

Dec.  1842. 

Crozier. 

-19  57 

— 0 11 

—20  08 

At  seat- 

— 53  56 

303  52 

Dec.  1842. 

Ross. 

-17  20 

-0  11 

— 17  31 

At  seat- 

-53  55 

304  18 

Sept.  1842. 

Ross. 

-18  12 

-0  08 

— 18  20 

At  seat- 

— 54  05 

304  26 

Sept.  1842. 

Crozier. 

-20  49 

-0  08 

-20  57 

At  seat- 

— 54  12 

305  15 

Sept.  1842. 

Crozier. 

-17  03 

— 0 08 

— 17  11 

At  seat- 

-55  45 

305  17 

Dec.  1842. 

Crozier. 

-19  43 

-0  08 

-19  51 

At  seat- 

-55  46 

305  17 

Dec.  1842. 

Ross. 

— 18  40 

-0  09 

-18  49 

At  seat- 

— 55  15 

305  39 

May  1846. 

Berard. 

-17  19 

-0  20 

-17  39 

At  sea- 

— 54  33 

306  13 

May  1846. 

Berard. 

— 14  14 

— 0 20 

— 14  34 

At  sea- 

-56  36 

306  38 

Dec.  1842. 

Ross. 

-17  35 

-0  09 

-17  44 

At  seat- 

— 56  54 

306  41 

Dec.  ] 842. 

Crozier. 

-19  13 

-0  09 

-19  22 

At  seat- 

— 58  25 

308  00 

Dec.  1842. 

Crozier. 

— 17  44 

-0  09 

— 17  53 

At  seat- 

-58  29 

308  13 

Dec.  1842. 

Ross. 

— 17  45 

-0  09 

-17  54 

At  seat- 

-59  28 

308  20 

Dec.  1842. 

Crozier. 

-21  05 

-0  09 

— 21  14 

At  seal. 

-59  54 

308  28 

Dec.  1842. 

Ross. 

-17  49 

-0  09 

— 17  58 

At  seat- 

— 52  52 

309  34 

May  1846. 

Berard. 

— 14  02 

— 0 20 

— 14  22 

At  sea. 

-57  30 

351  40 

Mar.  1843. 

Crozier. 

+ 10  29 

— 0 25 

+ 10  04 

At  seat- 

— 57  33 

352  04 

Mar.  1843. 

Ross. 

12  11 

— 0 25 

11  46 

At  seat- 

-57  16 

352  52 

Mar.  1843. 

Crozier. 

11  11 

0 25 

10  46 

At  seat- 

-57  06 

352  53 

Mar.  1843. 

Ross. 

13  06 

— 0 25 

12  41 

At  seat- 

— 56  12 

354  46 

Mar.  1843. 

Crozier. 

12  05 

— 0 25 

11  40 

At  seat- 

— 56  15 

354  56 

Mar.  1843. 

Ross. 

13  13 

— 0 25 

12  48 

At  seat- 

-54  11 

359  08 

Mar.  1843. 

Ross. 

16  58 

-0  25 

16  33 

At  seat- 

— 54  18 

.359  38 

Mar.  1843. 

Crozier. 

14  39 

— 0 25 

14  14 

At  sea. 

-59  02 

4 09 

Jan.  1845. 

Moore  and  Clerk. 

17  30 

-0  45 

16  45 

At  seat- 

— 55  29 

5 54 

Jan,  1845. 

Moore  and  Clerk. 

21  23 

-0  45 

20  38 

At  seat- 

— 53  52 

6 12 

Jan.  1845. 

Moore  and  Clerk. 

21  24 

-0  45 

20  39 

At  seat- 

-52  56 

7 53 

Jan.  1845. 

Moore  and  Clerk. 

23  46 

-0  45 

23  01 

At  seat- 

-51  47 

9 34 

Jan.  1845. 

Moore  and  Clerk. 

23  37 

— 0 45 

22  52 

At  seat- 

-50  45 

10  18 

Jan.  1845. 

Moore  and  Clerk. 

23  55 

-0  45 

23  10 

At  seat- 

Between  the  latitudes  of  —60°  and  — 70* 

> 

— 64  40 

302  07 

Jan.  1843. 

Crozier. 

— 24  07 

0 00 

-24  07 

At  seat- 

-64  39 

i302  36 

.Jan.  1843. 

Ross. 

— 22  14 

0 00 

— 22  14 

At  seat- 

LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC 


233 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

Correc- 
tion for 

Corrected 

Declina- 

Remarks. 

tion. 

Epoch. 

tion. 

Between  the  latitudes  of  —60°  and  —70°  (continued). 


-64 

40 

302 

40 

Jan. 

1843. 

Crozier. 

o 

-24 

05 

o 

0 

00 

o 

-24 

05 

At  seaf. 

— 64 

38 

302 

49 

Jan. 

1843. 

Ross. 

— 23 

03 

0 

00 

— 23 

03 

At  seaf. 

-64 

41 

302 

52 

Jan. 

1843. 

Crozier. 

— 23 

52 

0 

00 

— 23 

52 

At  seaf. 

-64 

32 

302 

55 

Jan. 

1843. 

Crozier. 

-23 

38 

0 

00 

-23 

38 

At  seaf. 

-64 

19 

303 

03 

Jan. 

1843. 

Ross. 

-21 

53 

0 

00 

-21 

53 

At  seaf. 

— 64 

44 

303 

10  'Jan. 

1843. 

Ross. 

— 21 

13 

0 

00 

-21 

13 

At  seaf. 

-64 

44 

303 

10  jjan. 

1843. 

Ross. 

— 21 

48 

0 

00 

-21 

48 

At  seaf. 

-64 

20 

303 

12  i.Jan. 

184.3. 

Crozier. 

— 23 

45 

0 

00 

-23 

45 

At  seaf. 

-64 

38 

303 

30  Jan. 

1843. 

Crozier. 

— 23 

05 

0 

00 

— 23 

05 

At  seaf. 

-64 

31 

303 

38 

Jan. 

1843. 

Ross. 

—22 

53 

0 

00 

— 22 

53 

At  seaf. 

-64 

05 

303 

47 

Jan. 

1843. 

Ross. 

— 22 

05 

0 

00 

— 22 

05 

At  seaf. 

-64 

15 

303 

49 

Jan. 

1843. 

Ross. 

— 21 

07 

0 

00 

— 21 

07 

At  seaf. 

-64 

11 

303 

50 

Jan. 

1 84.3. 

Crozier. 

—22 

43 

0 

00 

-22 

43 

At  seaf. 

-64 

26 

303 

52 

Jan. 

1843. 

Ross. 

— 22 

44 

0 

00 

—22 

44 

At  seaf. 

-64 

05 

303 

55 

Jan. 

1843. 

Crozier. 

— 22 

21 

0 

00 

— 22 

21 

At  seaf. 

-64 

23 

304 

00 

Jan. 

1843. 

Ross. 

— 22 

43 

+ 0 

03 

— 22 

40 

At  seaf. 

-64 

06 

304 

03 

Jan. 

1843. 

Ross. 

-21 

10 

+ 0 

03 

21 

07 

At  seaf. 

-64 

16 

304 

05 

.Tan. 

184.3. 

Ross. 

— 22 

25 

+0 

03 

— 22 

22 

At  seaf. 

-64 

33 

304 

05 

Jan. 

1843. 

Crozier. 

-22 

23 

+ 0 

03 

-22 

20 

At  seaf. 

— 64 

24 

304 

10 

Jan. 

1843. 

Ross. 

— 21 

10 

+ 0 

03 

-21 

07 

At  seaf. 

-64 

04 

304 

11 

.Tan. 

1843. 

Crozier. 

— 22 

40 

+ 0 

03 

-22 

37 

At  seaf. 

-64 

17 

304 

17 

Jan. 

1843. 

Crozier. 

-22 

22 

+ 0 

03 

— 22 

19 

At  seaf. 

-64 

04 

304 

18 

Jan. 

1843. 

Ross. 

—21 

02 

+ 0 

03 

-20 

59 

At  seaf. 

-64 

19 

304 

20 

Jan. 

1843. 

Ross. 

— 21 

36 

+ 0 

03 

-21 

33 

At  seaf. 

-64 

00 

304 

22 

Jan. 

1843. 

Crozier. 

— 22 

54 

+ 0 

03 

— 22 

51 

At  seaf. 

-63  47 

304 

31 

Dec. 

1842. 

Crozier. 

— 22 

19 

+ 0 

03 

— 22 

16 

At  seaf. 

-64 

17 

304 

42 

Jan. 

1843. 

Crozier. 

-21 

51 

+ 0 

03 

-21 

48 

At  seaf. 

-64 

01 

305 

00 

Feb. 

1843. 

Ross. 

— 21 

01 

+ 0 

03 

— 20 

58 

At  seaf. 

-63 

49 

305 

00 

Dec. 

1842. 

Ross. 

— 22 

27 

+ 0 

03 

— 22 

24 

At  seaf. 

-64 

03 

305 

18 

Jan. 

1843. 

Crozier. 

— 22 

02 

+ 0 

03 

-21 

59 

At  seaf. 

— 64 

12 

305 

20 

Feb. 

1843. 

Crozier. 

-21 

51 

+ 0 

03 

—21 

48 

At  seaf. 

—62 

54 

305 

41 

Dec. 

1842. 

Ross. 

— 20 

52 

— 0 

02 

— 20 

54 

A.t  seaf. 

-64 

20 

306 

00 

Jan. 

1843. 

Crozier. 

— 21 

40 

+ 0 

02 

— 21 

38 

At  seaf. 

-62 

39 

306 

12 

Dec. 

1842. 

Crozier. 

-21 

30 

-0 

02 

-21 

32 

At  seaf. 

-62 

00 

307 

52 

Dec. 

1842. 

Crozier. 

—20 

25 

— 0 

02 

— 20 

27 

At  seaf. 

—62 

18 

308 

03 

Dec. 

1842. 

Ross. 

-19 

03 

-0 

02 

-19 

05 

At  seaf. 

—62 

20 

308 

12 

Dec. 

1842. 

Crozier. 

—21 

21 

— 0 

02 

—21 

23 

At  seaf. 

-64 

10 

309 

30 

Feb. 

1843. 

Crozier. 

-19 

14 

-0 

02 

-19 

16 

At  seaf. 

-64 

41 

316 

00 

Feb. 

1843. 

Crozier. 

-15 

43 

-0 

06 

— 15 

49 

At  seaf. 

-64 

36 

316 

05 

Feb. 

1843. 

Ross. 

— 13 

41 

— 0 

06 

-13 

47 

At  seaf. 

-64 

50 

316 

40 

Feb. 

1843. 

Crozier. 

— 15 

01 

-0 

06 

— 15 

07 

At  seaf. 

-64 

38 

316 

57 

Feb. 

1843. 

Ross. 

— 13 

32 

-0 

06 

-13 

38 

At  seaf. 

-64 

04 

318 

29 

Feb. 

1843. 

Crozier. 

-13 

59 

-0 

10 

— 14 

09 

At  seaf. 

— 65 

06 

318 

57 

Feb. 

1843. 

Ross. 

— 12 

49 

-0 

10 

-12 

39 

At  seaf. 

-63 

58 

321 

43 

Feb. 

1843. 

Crozier. 

-10 

13 

-0 

16 

-10 

29 

At  seaf. 

-63 

57 

322 

00 

Feb. 

1843. 

Ross. 

- 9 

11 

— 0 

16 

- 9 

27 

At  seaf. 

—62 

38 

328 

00 

Feb. 

184.3. 

Ci’ozier. 

- 7 

30 

-0 

16 

- 7 

46 

At  seaf. 

—62 

41 

328 

27 

Feb. 

1843. 

Ross. 

- 6 

09 

-0 

16 

- 6 

25 

At  seaf. 

-62 

20 

330 

30 

Feb. 

1843. 

Ross. 

— 4 

41 

— 0 

16 

— 4 

57 

At  seaf. 

—62 

09 

332 

38 

Feb. 

1843. 

Crozier. 

— 3 

43 

-0 

16 

— 3 

59 

At  seaf. 

-62 

06 

333 

43 

Feb. 

1843. 

Ross. 

— 3 

48 

-0 

25 

— 4 

13 

At  seaf. 

-62 

00 

333 

44 

Feb. 

1843. 

Crozier. 

- 2 

42 

-0 

25 

— 3 

07 

At  seaf. 

-61 

55 

333 

48 

Feb. 

1843. 

Ross. 

— 3 

41 

— 0 

25 

— 4 

06 

At  seaf. 

-61 

32 

335 

33 

Feb. 

1843. 

Crozier. 

— 0 

34 

-0 

25 

- 0 

59 

At  seaf. 

-61 

36 

336 

20 

Feb. 

1843. 

Ross. 

- 0 

42 

-0 

25 

— 1 

07 

At  seaf. 

-70 

43 

343 

12 

Mar. 

1843. 

Crozier. 

2 

01 

— 0 

23 

1 

38 

At  seaf. 

234 


LINES  OF  MAGNETIC  DECLINATION  IN  THE  ATLANTIC. 


Table  XII.  (Continued.) 


Lat. 

Long. 

Date. 

Observer. 

Observed 

Declina- 

tion. 

Correc- 
tion for 
Epoch. 

Corrected 

Declina- 

tion. 

Remarks. 

Between  the  latitudes  of  — 60' 

and  —70°  (continued). 

-70  50 

343  34 

Mar.  1843.  Ross. 

o / 

3 03 

o / 

— 0 23 

2 40 

At  seaf. 

-62  18 

343  44 

Feb.  1843. 

Crozier. 

3 01 

— 0 25 

2 36 

At  seaf. 

— 62  24 

343  58 

Feb.  1843. 

Crozier. 

5 00 

— 0 25 

4 35 

At  seaf. 

— 62  52 

344  33 

Feb.  1843. 

Ross. 

4 49 

— 0 25 

4 24 

At  seaf. 

-64  48 

345  16 

Feb.  1843. 

Ross. 

5 11 

— 0 25 

4 46 

At  seaf. 

-69  42 

345  20 

Mar.  1843. 

Crozier. 

1 35 

— 0 23 

1 12 

At  sea*)*. 

-69  13 

345  55 

Mar.  1843. 

Ross. 

3 25 

— 0 23 

3 02 

At  seaf. 

—64  29 

346  02 

Mar.  1843. 

Ross. 

4 19 

— 0 25 

3 54 

At  seaf. 

— 64  06 

346  15 

Mar.  1843. 

Crozier. 

5 15 

— 0 25 

4 50 

At  seaf. 

—64  14 

346  15 

Feb.  1843. 

Crozier. 

5 01 

-0  25 

4 36 

At  seaf. 

-66  10 

346  40 

Mar.  1843. 

Crozier. 

5 25 

— 0 25 

5 00 

At  seaf. 

-68  30 

346  50 

Mar.  1843. 

Crozier. 

3 51 

— 0 25 

3 26 

At  seaf. 

—68  10 

347  45 

Mar.  1 843. 

Crozier. 

5 18 

-0  25 

4 53 

At  seaf. 

— 68  08 

348  10 

Mar.  1 843. 

Crozier. 

3 48 

— 0 25 

3 23 

At  seaf. 

-61  16 

348  56 

Mar.  1843. 

Ross. 

8 49 

- 0 25 

8 24 

At  seaf. 

-61  16 

349  00 

Mar.  1843. 

Crozier. 

7 07 

— 0 25 

6 42 

At  seaf. 

-65  01 

349  04 

Feb.  1843. 

Crozier. 

6 34 

— 0 25 

6 09 

At  seaf. 

—65  08 

349  50 

Feb.  1843. 

Ross. 

7 35 

— 0 25 

7 10 

At  seaf. 

-67  12 

350  36 

Mar.  1843. 

Crozier. 

6 43 

— 0 25 

6 18 

At  seaf. 

— 66  00 

351  00 

Mar.  1843. 

Crozier. 

8 47 

— 0 25 

8 22 

At  seaf. 

— 66  40 

351  39 

Mar.  1843. 

Ross. 

8 54 

— 0 25 

8 29 

At  seaf. 

—61  12 

9 30 

Feb.  1845. 

Moore  and  Clerk. 

20  29 

-0  40 

19  49 

At  seaf. 

—62  03 

12  45 

Feb.  1845. 

Moore  and  Clerk. 

22  07 

— 0 40 

21  27 

At  seaf. 

— 6l  54 

16  40 

Feb.  1845. 

Moore  and  Clerk. 

23  11 

— 0 40 

22  31 

At  seaf. 

-6l  49 

19  13 

Feb.  1845. 

Moore  and  Clerk. 

26  16 

— 0 40 

25  36 

At  seaf. 

-62  05 

20  58 

Feb.  1845. 

Moore  and  Clerk. 

28  05 

-0  40 

27  25 

At  seaf. 

CONTENTS. 


Introduction  173 

Observations  employed; — 

A.  Sea  Observations,  uncorrected  for  the  Ship’s  Magnetism  1/5 

B.  Sea  Observations,  corrected  for  the  Ship’s  Magnetism  176 

C.  Land  Observations,  on  Coasts  and  Islands  176 

Discussion  of  the  Corrections  for  the  Ship’s  Magnetism 177 

Arrangement  of  the  Observations  in  Groups  195 

Table  of  the  Declination  in  1840  at  the  intersection  of  every  5°  of  Latitude  and  Longitude  202 

Table  of  Secular  Change  26^ 

Comjiarison  with  M.  Gauss’s  General  Theory  204 

General  Table  of  the  observations  employed  in  the  Map  arranged  according  to  Latitude  and  Longitude...  20/ 


[ 235  ] 


XIII.  Contributions  to  the  Chemistry  of  the  Urine. — Paper  III. 

Part  I.  On  the  Variations  of  the  Acidity  of  the  Urine  in  the  state  of  Health. 

Part  II.  On  the  simultaneous  Variations  of  the  amount  of  Uric  Acid,  and  the  Acidity 
of  the  Urine  in  the  state  of  Health. 

Part  III.  On  the  Variations  of  the  Sulphates  in  the  state  oj  Health,  and  on  the 
influence  of  Sulphuric  Acid,  Sulphur  and  Sulphates,  on  the  amount  of  Sul- 
phates in  the  Urine. 

^^Hknrv  Bence  5oyiE.s,M.D.,M.A.  Cantab.,  F.R.S.,  Physician  to  St.  George's  Hospital. 

Received  November  20,  1848, — Read  January  25,  1849. 


Part  I. — On  the  Variations  of  the  Acidity  of  the  Urine  in  the  state  of  Health. 

In  the  Philosophical  Transactions  for  1845,  I showed  that  not  unfrequently  in 
London,  the  urine  was  found  in  many  persons  to  be  alkaline  from  fixed  alkali  ; and 
I mentioned  that  Dr,  Andrews,  at  Belfast,  had  found  the  water  passed  at  noon  of 
two-thirds  of  the  students  of  his  class  to  be  alkaline. 

It  appeared  to  me  to  be  a matter  of  great  interest  to  determine  quantitatively  the 
daily  variations  in  the  acidity  and  alkalescence  of  the  urine  in  the  state  of  health  ; 
to  trace,  if  possible,  the  cause  of  the  variations  ; to  determine  the  effect  of  some 
medicines ; at  the  least  until  this  was  done  I could  draw  no  conclusions  regarding 
the  effect  of  diseases  on  the  acidity  of  the  urine. 

In  examining  quantitatively  the  variations  at  different  hours  of  the  day,  it  was 
immediately  found  that  there  was  no  fixed  degree  of  acidity  of  the  urine  ; that  the 
acidity  did  not  vary  with  the  specific  gravity,  but  that  there  was  a never-ceasing- 
change,  an  ebb  and  flow,  in  the  acid  reaction  of  the  urine,  which  was  quite  inde- 
pendent of  the  specific  gravity. 

The  degree  of  acidity  of  the  urine  was  found  generally  to  be  greatest  a short  time 
before  food  was  taken;  and  after  food  the  acidity  was  diminished,  until  about  three 
hours  after  breakfast,  and  four  or  five,  or  six  hours  after  dinner,  when  it  reached  the 
minimum  point ; after  which  it  again  rose  and  attained  its  height  previous  to  food 
being  again  taken. 

A healthy  man  was  the  subject  of  the  following  experiments  : for  three  months  he 
had  taken  strong  exercise,  walking  above  700  miles.  Food  was  taken  twice  daily. 
The  exercise  was  moderate  during  the  experiments,  from  three  to  four  hours  daily. 

The  urine  not  unfrequently  showed  most  marked  alkalescence  from  fixed  alkali. 
Rarely  even  phosphate  of  lime  was  deposited.  Five  or  six  hours  afterwards  the 


2:36 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


acidity  reached  its  highest  point,  but  did  not  on  any  occasion  cause  the  formation  of 
uric  acid  crystals. 

The  mode  of  examination  was  the  following.  Two  test  solutions  were  made,  the 
one  with  carbonate  of  soda,  the  other  with  dilute  sulphuric  acid.  Each  measure  of 
either  test  was  made  equivalent  to  1^2-th  of  a grain  of  dry  and  pure  carbonate  of  soda. 

A bottle  containing  1000  grains  at  least  of  urine  was  filled  and  weighed.  The  urine 
was  heated  in  a cup  to  120°,  and  then  the  test  solution  was  dropped  in  from  a gra- 
duated tube;  so  that  the  urine,  when  acid,  was  made,  by  alkali,  just  neutral  to  the 
most  delicate  test-paper;  and  when  alkaline,  it  was  made  just  neutral  by  acid.  The 
number  of  measures  required  gave  the  degree  of  acidity  or  alkalescence  of  the  urine. 

In  the  second  part  of  this  paper,  it  will  be  seen  from  experiments  made  four  months 
previously  to  these,  that  the  same  kind  of  variations  took  place  then  ; and  in  the  same 
case  two  years  before,  and  again  even  three  years  previous  to  these  experiments,  the 
same  fact  was  noted. 

Thus,  October  13,  1846,  breakfast  on  bread  and  meat  at  9 a.m. 

Urine  passed  at  1 p.m.,  clear.  Specific  gravity  . . 1022’8.  Alkaline. 

Urine  passed  at  3 P.M.,  clear.  Specific  gravity  . . 1019  9.  Acid. 

And  October  28,  1845,  breakfast  at  b''  15“. 

h m 

Urine  passed  at  10  a.m.  Acid. 

Urine  passed  at  12  30  p.m.  Alkaline. 

Urine  passed  at  3 Acid. 

(1.)  October  14,  1848.  Breakfast  on  bread,  meat  and  coffee,  at  8'*  45™  a.m.  Dinner 


at  5^  50™  P.M.  Fish, 

meat,  potatoes  and  water. 

h 

m 

Spec.  gr. 

Acidity  per  1000  grs.  of 

urine.  Appearances. 

Water  passed  at 

7 

15  A.M. 

thrown  away 

. 

Water  passed  at 

8 

45 

= 1021T 

-b  1 1-75  measures. 

Clear. 

Water  passed  at 

9 

55 

= 1023-5 

+ 8-79 

Clear. 

Water  passed  at 

11 

15 

= 1022-7 

— 11-73 

Clear. 

Water  passed  at 

12 

= 1024-4 

— 29-28 

Thick  from  phosphates. 

Water  passed  at 

12 

50  P.M. 

= 1024-0 

— 10-74 

Clear. 

Water  passed  at 

2 

15 

= 1021-5 

+ 6-85 

Clear. 

Water  passed  at 

3 

50 

= 1024-1 

+ 15-62 

Clear. 

Water  passed  at 

5 

50 

= 1024-4 

+21-47 

Clear. 

Water  passed  at 

7 

55 

= 1029-6 

+ 15-54 

Thick  from  urates. 

Water  passed  at 

10 

45 

= 1029-8 

- 5-82 

Clear. 

Water  passed  at 

6 

30  A.M. 

= 1023-3 

+ 9-77 

Clear. 

Water  passed  at 

7 

40 

= 1025-3 

+ 13-65 

Clear. 

(2.)  Breakfast  at 
at  5''  45™  P.M. 

8*1  45™ 

A.M.,  the  same  as  the  day  previous.  Dinner  the  same, 

Water  passed  at 

8 

45 

= 1025-6 

+ 1 5-6O  measures. 

Clear. 

Water  passed  at 

10 

= 1021-3 

+ 11-74 

Clear. 

OF  THE  ACIDITY  OF  THE  URINE. 


237 


Water  passed  at 

h 

m 

Spec.  gr. 

Acidity  per  1000  grs.  of  urine.  Appearances. 

11 

20  A.M. 

= 1024-9 

— 12-68  measures. 

Clear. 

Water  passed  at 

12 

20  p.M.  ' 

j-  =1029-2 

-14-57  1 

Thick  from  phosphates 

Water  passed  at 

12 

45  J 

Clear. 

Water  passed  at 

3 

15 

= 1028-4 

+ 13-61 

Clear. 

Water  passed  at 

5 

45 

= 1026-6 

+22-40 

Clear. 

Water  passed  at 

9 

= 1032-9 

+ 13-55 

Thick  from  urates. 

Water  passed  at 

11 

10 

= 1030-4 

+ 3-88 

Clear. 

Water  passed  at 

2 

30  A.M. 

= 1011-4 

+ 5-93 

Clear. 

Water  passed  at 

7 30 

= 1020-6 

+ 11*75 

Clear. 

(3.)  Breakfast 

at  8^  45“'  A.M.,  the  same 

as  the  day  previous 

. Dinner  at  5'’  5™  p.m. 

Water  passed  at 

8 

45 

= 1024-8 

+ 19-51  measures. 

Thick  urates. 

Water  passed  at 

9 

50 

= 1020-6 

+ 12-73 

Clear. 

Water  passed  at 

10 

50 

= 1021-8 

+ 1-95 

Clear. 

Water  passed  at 

12 

50  p.M. 

= 1027-2 

- 1-94 

Clear. 

Water  passed  at 

2 

50 

= 1024-7 

+ 10-73 

Clear. 

Water  passed  at 

5 

5 

= 1024-9 

+ 18-53 

Clear. 

Water  passed  at 

7 

35 

= 1029-2 

+ 15-54 

Thick  from  urates. 

Water  passed  at 

10 

5 

= 1027-2 

- 7-78 

Clear. 

Water  passed  at 

2 

15  A.M. 

= 1022-0 

+ 8-80 

Clear. 

Water  passed  at 

6 

45 

= 1024-6 

+ 16-59 

Clear. 

Water  passed  at 

7 

45 

= 1024-8 

+20-49 

Thick  from  urates. 

Water  passed  at 

8 

45 

= 1022-5 

+ 13-69 

Clear. 

From  these  experiments,  which  lasted  three  days,  it  appears  that  before  each  meal 
the  urine  showed  the  highest  degree  of  acidity ; and  the  water  passed  two  or  tliree 
hours  after  food  always  showed  a lower  degree  of  acidity  than  that  made  before  food. 
The  decrease  continued  until  three  hours  after  breakfast,  and  five  or  six  hours  after 
dinner,  when  it  reached  the  lowest  point.  The  acidity  of  the  urine  then  increased 
until  just  before  food,  when  it  again  reached  the  highest  limit. 

Tims,  when  breakfast  was  taken  at  half-past  eight,  the  acidity  of  1000  grains  of 
the  urine  then  passed  was  sufficient  to  neutralize  about  one  grain  of  dry  and  pure 
carbonate  of  soda.  At  twelve  o’clock  the  urine  was  as  alkaline  as  if  every  1000  grains 
of  urine  contained  two  and  a half  grains  of  carbonate  of  soda.  At  half-past  five,  just 
before  dinner,  the  acidity  had  increased,  so  that  every  1000  grains  of  urine  was  so 
acid  as  to  require  two  grains  of  carbonate  of  soda  to  neutralize  it.  At  half-past  ten 
the  acidity  had  diminished,  so  that  every  1000  grains  of  urine  was  as  alkaline  as  if 
they  contained  half  a grain  of  carbonate  of  soda.  After  this  it  probably  became  more 
alkaline,  and  then  still  longer  after  food  became  acid  ; and  by  half-past  eight  in  the 
morning,  each  1000  grains  of  urine  required  about  a grain  and  one-third  of  carbonate 
of  soda  to  neutralize  the  acid  reaction. 

The  same  changes  were  observed  on  each  of  the  two  following  days.  These  varia- 

MDCCCXLIX.  2 I 


238 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


tions  are  seen  in  the  accompanying  Plate  XVI.  better  than  they  can  be  set  forth  in 
words,  and  the  influence  of  digestion  on  the  acidity  of  the  urine  is  made  evident. 

There  is  a slight  exception  which  requires  notice.  In  the  last  day,  before  break- 
fast, at  6'‘  45™  A. M.,  the  specific  gravity  was  1024‘6,  and  every  1000  grains  had  an 
acidity  marked  by  16*59  measures.  At  7^  45™  p.m.  the  acidity  had  increased  to  20*45, 
the  specific  gravity  having  hardly  changed.  At  8*^  45™  a. m.,  just  before  breakfast, 
the  acidity  had  decreased  to  13*69,  with  a very  slight  diminution  of  the  specific 
gravity. 

As  a test  of  the  truth  of  the  conclusions  drawn  from  the  previous  experiments,  the 
variations  of  the  acidity  were  noted  when  no  food  was  taken  in  the  morning,  and  the 
following  results  were  obtained. 

(4.)  No  food  was  taken  from  dinner  the  previous  day  at  5^  30™  p.m.,  to  dinner  this 
day  at  5^  10™  p.m.  Both  days  the  food  was  meat,  soup,  potatoes,  bread  and  water. 
The  urine  was  passed  as  frequently  as  possible. 


h 

m 

Spec.  gr. 

Acidity  per  1000 

grs.  of  urine. 

Water  passed  at 

6 

10  A. M, 

1025*7 

+ 15*59  measures.  Clear. 

Water  passed  at 

7 

50  No  breakfast.  1028*6 

+ 13*61 

Thick  from  urates. 

Water  passed  at 

9 

10 

1026*3 

+ 15*58 

Thick  from  urates. 

Water  passed  at 

11 

20 

1025*0 

+ 12*68 

Thick  from  urates. 

Water  passed  at 

12 

30  P.M. 

1025*7 

+ 13*64 

Thick  from  urates. 

Water  passed  at 

2 

45 

1028*0 

+ 15*56 

Thick  from  urates. 

Water  passed  at 

5 

10  Dinner. 

1031*3 

+ 15*51 

Thick  from  urates. 

Water  passed  at 

7 

10 

1034*6 

+ 13*53 

Thick  from  urates. 

Water  passed  at 

9 

5 

1029*4 

- 7-77 

Clear. 

Water  passed  at 

1 1 

1029*5 

- 291 

Clear, 

Water  passed  at 

5 

40  A.M. 

1026*9 

+ 10*71 

Clear. 

Water  passed  at 

8 

45  Breakfast. 

1028*0 

+ 17-51 

Thick  from  urates. 

Water  passed  at 

10 

15 

1026*3 

+ 9*74 

Thick  from  urates. 

Water  passed  at 

12 

30  P.M. 

1028*7 

- 14*57 

Thick  from  phosphates. 

Water  passed  at 

3 

10 

1028*8 

— 0*97 

Clear. 

Plate  XVII.  shows  these  variations,  and  contrasts  the  slight  changes  when  break- 
fast was  not  taken,  with  the  great  changes  after  food. 

From  six  in  the  morning  until  dinner  was  taken,  soon  after  five,  the  variations  in 
the  acidity  of  the  urine  were  very  small  ; requiring  rather  more  than  one  grain  of 
carbonate  of  soda  to  neutralize  1000  grains  of  the  urine.  Four  hours  after  dinner 
the  urine  was  so  diminished  in  acidity,  that  every  1000  grains  of  urine  had  an  alka- 
line reaction  equal  to  two-thirds  of  a grain  of  dry  and  pure  carbonate  of  soda.  Two 
hours  after  this  the  acidity  was  found  to  be  increased,  and  by  breakfast  time,  the 
following  morning,  1000  grains  of  urine  required  a grain  and  a half  of  carbonate  of 
soda  to  neutralize  their  acidity.  Four  hours  after  breakfast  the  acidity  had  decreased 
so  much,  that  1000  grains  of  urine  were  as  alkaline  as  if  they  had  contained  nearly  a 
grain  and  a quarter  of  carbonate  of  soda. 


OF  THE  ACIDITY  OF  THE  URINE. 


239 


II.  I next  endeavoured  to  determine  whether  different  kinds  of  food  caused  dif- 
ferent changes  in  the  acidity  of  the  urine.  For  three  days  consecutively  animal  food 
only  was  taken  at  8*^  45™  a.m.  and  5*^  40™  p.m.  Beefsteaks,  eggs,  weak  coffee,  milk  and 
water. 

h m Spec.  gr.  Acidity  per  1000  grs.  of  urine. 

(5.)  Water  passed  at  7 0 a.m.  thrown  away. 


Water  passed  at 

8 

45 

1024-6 

4-  7*80  measures.  Clear. 

Water  passed  at 

9 

50 

1019-9 

— 7-84 

Clear. 

Water  passed  at 

10 

55 

1020-2 

— 30-38 

Thick  from  phosphates. 

Water  passed  at 

12 

55  P.M. 

1025-2 

- 9-73 

Clear. 

Water  passed  at 

3 

0 

1027-0 

-f  13-63 

Thick  from  urates. 

Water  passed  at 

5 

40 

1029-5 

-1-19-42 

Thick  from  urates. 

Water  passed  at 

8 

5 

1032-8 

-1-14-52 

Thick  from  urates. 

Water  passed  at 

10 

30 

1030-3 

0 

Thick  from  urates. 

Water  passed  at 

5 

0 A.M. 

1022-9 

-1-10-75 

Clear. 

Water  passed  at 

7 

10 

1026-1 

-f  17-52 

Clear. 

(6.)  Breakfast  at  8^  50™  a.m.  Dinner  at  5''  40™  p.m. 
as  the  previous  day. 

Animal  food  only  ; the  same 

Water  passed  at 

8 

50 

10-26-7 

-1-1 0-71  measures.  Clear. 

Water  passed  at 

10 

10 

1025-3 

-f  1-95 

Clear. 

Water  passed  at 

11 

10 

1024-6 

— 26-35 

Thickish  from  phosphates. 

Water  passed  at 

12 

30  P.M. 

1025-3 

— 29-26 

Thick  from  phosphates. 

Water  passed  at 

1 

50 

1025-5 

— 1-95 

Clear. 

Water  passed  at 

3 

30 

1025-0 

+ 9-75 

Clear. 

Water  passed  at 

5 

40 

1027-4 

-f  17-52 

Clear. 

Water  passed  at 

7 

40 

1031-7 

-1-11-63 

Thick  from  urates. 

Water  passed  at 

11 

0 

1028-7 

— 2-91 

Clear. 

Water  passed  at 

7 

15  A.M. 

1024-6 

-1-13-66 

Clear. 

(7-)  Breakfast  at  8^  50™  a.m.  Dinner  at  5*^  50™  p.m.  Animal  food  only  ; the  same 
as  the  previous  day. 


Water  passed  at 

8 

50 

10270 

-f  15-58  measures. 

Thick  from  urates. 

Water  passed  at 

10 

8 

1026-5 

+ 1-94 

Cloudy. 

Water  passed  at 

1 1 

10 

1026-9 

— 24-34 

7+ick  from  phosphates, 

Water  passed  at 

12 

10  P.M. 

1029-8 

— 26-21 

Thick  from  phosphates, 

Water  passed  at 

2 

15 

1025-2 

-f  3 90 

Cloudy. 

Water  passed  at 

3 

40 

1028-1 

-f  13-61 

Cloudy. 

Water  passed  at 

5 

55 

1029-7 

-f- 18-45 

Cloudy. 

Water  passed  at 

7 

55 

1035-4 

4-16-41 

Thick. 

Water  passed  at 

10 

55 

1031-7 

-f  2-90 

Thick. 

Water  passed  at 

6 

0 A.M. 

1026-0 

-f  12-67 

Clear. 

Water  passed  at 

7 

40 

1028-6 

-f  18-46 

Thick. 

Water  passed  at 

8 

55 

1028-7 

+ 20-41 

2 1 2 

Thick. 

240 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


From  the  comparison  of  these  numbers,  as  seen  in  Plate  XVIIL,  with  those  ob- 
tained when  a mixed  diet  was  taken,  as  in  Plate  XVI.,  it  is  apparent, — 

1st.  That  the  diminution  of  the  acidity  after  food  is  more  marked,  and  continues 
longer  when  animal  food  only  is  taken,  than  it  does  when  mixed  diet  is  eaten. 

2nd.  That  the  acidity  before  food  rises  rather  higher  with  a mixed  diet  than  it 
does  with  animal  food  only. 

There  is  the  same  exception  observable  on  the  second  day  of  animal  food  as  was  seen 
the  third  day  when  mixed  diet  was  taken.  At  ten  minutes  after  seven  the  urine  had 
an  acidity  for  every  1000  grains  marked  by  17‘52  measures.  At  fifty  minutes  after 
eight  (just  before  breakfast)  the  acidity  was  diminished  to  10'71  measures.  There 
was  but  little  difference  in  the  specific  gravity  of  the  two  quantities. 

For  three  days  consecutively  vegetable  food  only  was  taken,  twice  each  day. 
Breakfast  at  8’'  55“*  a.m.  Dinner  at  6*^  15“  p.m. 


(8.)  Water  passed  at 

h m 

8 55  a.m. 

Spec.  gr. 

10287 

Acidity  per  1000  grs.  of 

+20*41  measures. 

urine. 

Thick  from  urates. 

Water  passed  at 

10  20 

1028*0 

+ 12*64 

Thick. 

Water  passed  at 

11  40 

1027*5 

+ 7-78 

Thick. 

Water  passed  at 

1 0 P.M. 

1028*4 

+ 7-78 

Thick. 

Water  passed  at 

2 55 

1027*8 

+ 8*75 

Thick. 

Water  passed  at 

6 15 

1031*5 

+20*36 

Thick. 

Water  passed  at 

8 20 

1036*4 

+ 15*43 

Thick. 

Water  passed  at 

11  5 

1035*3 

+ 16*42 

Thick. 

Water  passed  at 

3 30  A.M. 

1030*1 

+ 12*62 

Thick. 

Water  passed  at 

7 30 

1030*1 

+20*38 

Thick. 

(9.)  Breakfast  at  8'‘  50“  a.m.  Dinner  at  5*‘ 

35“  P.M. 

Vegetable  food  only. 

Water  passed  at 

8 50 

1031*2 

+26*18  measures. 

Thick. 

Water  passed  at 

10  30 

1029*4 

+ 5*83 

Thick. 

Water  passed  at 

12  0 

1028*9 

0 

Clear. 

Water  passed  at 

2 10  P.M. 

1027*8 

+ 2*91 

Clear. 

Water  passed  at 

5 35 

1028*5 

+ 16*52 

Thick. 

Water  passed  at 

8 35 

1034*2 

+ 11*60 

Thick. 

Water  passed  at 

11  45 

1012*4 

+ 1-97 

Clear. 

Water  passed  at 

6 45  A.M. 

1009*1 

+ 5*94 

Clear. 

Water  passed  at 

8 55 

1020*5 

+ 14*69 

Clear. 

(10.)  Breakfast  at  8^  55“  a.m.  Dinner  at  5*^  55“  p.m. 

Vegetable  food  only.  At 

breakfast  about  two  ounces  of  honey 

were  taken. 

Water  passed  at 

10  0 

1013*5 

+ 7*89  measures. 

Clear. 

Water  passed  at 

10  35 

1009*1 

+ 4*95 

Clear. 

Water  passed  at 

11  30 

1018*9 

+ 4*90 

Clear. 

Water  passed  at 

12  50  p.m. 

1020*8 

+ 5*87 

Clear. 

Water  passed  at 

2 10 

1017-9 

+ 6*87 

Clear. 

OF  THE  ACIDITY  OF  THE  URINE. 


241 


h 

m 

Spec.  gr. 

Acidity  per  1000  grs.  of 

urine. 

Water  passed  at 

3 

30  P.M. 

1019-8 

-|-  8 82  measures. 

Clear. 

Water  passed  at 

5 

55 

1021-2 

-1-16-64 

Clear. 

Water  passed  at 

8 

30 

1030-9 

-fl7*46 

Thick  from  urates. 

Water  passed  at 

10 

50 

1023-4 

0 

Clear. 

Water  passed  at 

6 

30  A.M. 

1010-6 

H-  5-93 

Clear. 

Water  passed  at 

8 

45 

1020-9 

-f  8-81 

Clear. 

Breakfast  at  8^  45 

“ A.M.  on 

animal  food  only. 

Water  passed  at 

10 

20 

1023-1 

— 10-75  measures. 

Clear, 

Water  passed  at 

11 

0 

1022-9 

— 29-23 

Thick  from  phosphates. 

Water  passed  at 

12 

0 

1022-3 

-30-75 

Thick  from  phosphates. 

Water  passed  at 

12 

50  P.M. 

1023-5 

—25-40 

Thick  from  phosphates. 

Water  passed  at 

4 

30 

1027*6 

-1-13-62 

Thiek  from  urates. 

If  these  changes,  represented  in  Plate  XIX.,  are  compared  with  those  in  Plate 
XVIII.,  it  will  be  evident  that  the  diminution  of  the  acidity  of  the  urine  is  very  different, 
though  the  experiments  were  made  on  six  consecutive  days.  For  the  three  days  that 
vegetable  food  was  taken,  the  urine  never  was  markedly  alkaline  ; twice  it  was  neutral 
to  test-paper,  between  three  and  four  hours  after  breakfast ; but  it  never  became  so 
alkaline  as  when  the  diet  was  mixed,  or  consisted  of  animal  food  only.  The  breakfast, 
after  the  three  days  of  vegetable  food,  consisted  almost  entirely  of  animal  food,  and 
then,  for  at  least  two  hours  and  a half,  the  urine  was  highly  alkaline.  The  increase 
in  the  acidity  before  food  on  the  second  day  is  very  marked.  It  was  higher  than  on 
any  previous  occasion.  The  third  day,  before  dinner,  at  S*’  55“  p.m.,  the  acidity  per 
1000  grs.  urine  equaled  16'64  measures.  At  half-past  eight  it  had  increased  to  17‘46 
measures,  though  in  all  the  previous  experiments  the  acidity  diminished  after  dinner  ; 
but  at  lO'*  50“  P.M.  the  urine  had  become  neutral  to  test-paper.  Possibly  this  increase 
of  acidity  was  owing  to  the  honey  taken  at  breakfast. 

III.  On  the  Influence  of  Medicines,  (a.)  Sulphuric  acid. 

For  three  following  days  dilute  sulphuric  acid,  specific  gravity  1-1077?  was  taken, 
in  doses  of  three  drachms  daily.  In  all,  nine  drachms  of  acid  were  taken. 

Breakfast  as  in  experiments  (1.),  (2.),  (3.),  at  8^  45“a.m.  Dinner,  as  before,  at 
5h  45m  p jyj  Qne  drachm  of  dilute  acid,  in  two  ounces  of  distilled  water,  was  taken  at 
7h  45"*  Another  at  12^  45“  p.m.  The  last  at  4*^  50“  p.m. 

h m Spec.  gr.  Acidity  per  1000  grs.  of  urine. 

(11.)  Water  passed  at  7 45  a.m.  1024-8  -j- 20- 49  measures.  Thickish  from  urates. 


Water  passed  at  8 45  1022-5  -|-13-69  Clear. 

Water  passed  at  10  15  1012  6 + 8-88  Clear. 

Water  passed  at  11  25  1022-5  — 8-80  Clear. 

Water  passed  at  12  45  p.m.  1026-1  — 3-89  Clear. 

Water  passed  at  3 10  1023-4  -1-13-68  Clear. 

Water  passed  at  4 50  1024-1  -1-21-48  , Clear. 


242 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


h 

m 

Spec.  gr. 

Acidity  per  1000  grs. 

of  urine. 

Water  passed  at 

5 

45  P.M. 

1026'2 

-1-24-36  measures.  Clear. 

Water  passed  at 

10 

0 

1030-6 

- 7'76 

Clear. 

Water  passed  at 

3 

15  A.M. 

1018-1 

-i-  4-91 

Clear. 

Water  passed  at 

7 

0 

1020-1 

-+-14-70 

Clear. 

(12.)  The  following  day  breakfast  as 

before,  at  8^  40™  a.m. 

Dinner  as  before,  at 

5h  30“p,m.  a drachm  of  dilute 

sulphuric  acid  was  taken  at  8^*  10™,  12^  45™,  4^  30™. 

Water  passed  at 

8 

40 

1024-0 

-1-14-64  measures.  Thick  from  urates. 

Water  passed  at 

10 

0 

1013-4 

-f  7-88 

Clear. 

Water  passed  at 

11 

10 

1023-3 

— 13.-68 

Clear. 

Water  passed  at 

12 

0 

1026-9 

- 779 

Clear. 

Water  passed  at 

12 

45  P.M. 

1026-1 

— 3-89 

Clear. 

Water  passed  at 

3 

10 

1023-2 

d- 14-66 

Clear. 

Water  passed  at 

5 

30 

1024-0 

-f  20-50 

Clear. 

Water  passed  at 

7 

10 

1030-4 

-t- 24-26 

Thick  from  urates. 

Water  passed  at 

10 

35 

1032-6 

+ 6-77 

Very  thick  from  urates. 

Water  passed  at 

3 

35  A.M. 

1020-0 

-H  5-88 

Clear, 

Water  passed  at 

6 

50 

1020*1 

-1-12-74 

Clear. 

Water  passed  at 

7 

45 

1022-6 

-1-14-66 

Clear. 

(13.)  The  following  day  breakfast  as  before,  at  8^  40“*a.m. 

Dinner  as  before,  at 

5h  40nip.M.  Dilute  sulphuric  acid  was  taken  at  8’’,  D 25"*,  5**. 


Water  passed  at 

8 

40 

1023-4 

-|- 17’58  measures. 

Clear. 

Water  passed  at 

9 

50 

1018-5 

-1-10-80 

Clear. 

Water  passed  at 

11 

5 

1019-9 

-f  8-82 

Clear. 

Water  passed  at 

12 

5 P.M. 

1025-5 

~ 4-87 

Clear. 

Water  passed  at 

12 

55 

1026-0 

-f  3-89 

Clear. 

Water  passed  at 

2 

50 

1024-2 

-1-14-64 

Clear. 

Water  passed  at 

5 

40 

1023-5 

-f  19-54 

Clear. 

Water  passed  at 

7 

30 

1029-1 

4-12-63 

Thick  from  urates. 

Water  passed  at 

10 

50 

1029-0 

4-  2-91 

Clear. 

Water  passed  at 

5 

10  a.m. 

1016-1 

4-  8-85 

Clear. 

Water  passed  at 

6 

55 

1016-5 

4-11-80 

Clear. 

Water  passed  at 

8 

30 

1020-9 

4-13-71 

Clear. 

Plate  XX.  admits  of  a comparison  with  those  previously  given. 

The  nine  drachms 

of  dilute  sulphuric 

acid  do  not  appear  to  heighten  the  acidity  before  food,  though  the 

diminution  of  the  acidity  after  food  is  certainly  less  marked  than  when  no  acid  was 
taken,  and  mixed  diet  was  eaten.  In  the  third  part  of  this  paper,  on  the  Variations 
of  the  Sulphates  in  Health,  I shall  show  that  a similar  mode  of  inquiry  gave  no  posi- 
tive results  as  to  their  increase  in  the  urine  after  sulphuric  acid  was  taken  ; but  by 
examining  all  the  urine  passed  in  twenty-four  hours,  positive  results  were  obtained. 

A similar  course  was  therefore  adopted  regarding  the  acidity  of  the  urine. 


OF  THE  ACIDITY  OF  THE  URINE. 


243 


These  three  days’  variations  confirm  those  previously  given  ; all  show  the  influence 
of  digestion  ; the  constant  decrease  of  the  acidity  of  the  urine  after  food  was  taken, 
and  the  gradual  increase  of  acidity  as  the  food  is  absorbed. 

The  second  day,  before  breakfast,  it  may  be  observed  that  the  water  made  at  7 and 
at  8’’  40“a.m.,  had  very  nearly  the  same  degree  of  acid  reaction  ; that  is,  during  the 
last  hour  and  forty  minutes  before  breakfast  there  was  no  increase  in  the  acidity  of 
the  urine.  I have  previously  pointed  out  that  on  two  occasions  there  was  a diminu- 
tion of  the  acidity  of  the  urine  just  before  breakfast. 

It  may,  perhaps,  indicate  that  acid  is  sometimes  separated  from  the  blood  by  the 
stomach  previous  to  the  food  being  taken. 

A young  physician  with  an  irritable  stomach,  but  otherwise  in  good  health,  made 
the  following  observations  on  his  urine,  at  my  request,  for  seven  days.  Breakfast 
was  always  immediately  after  the  second  testing  of  the  water. 

February  20. — S'*  30™  a.m.  slightly  acid.  9 a m.  neutral.  1 p.m.  alkaline. 

February  21. — S'*  30“  a.m.  strongly  acid.  9 a.m.  slightly  acid.  12  a.m.  alkaline.  4 p.m. 
slightly  acid. 

February  22. — 7 a.m.  slightly  acid.  8**  30“  and  9 a.m.  alkaline.  2 p.m.  alkaline.  4 p.m. 
neutral.  5**  30™  p.m.  slightly  acid. 

February  23. — S'*  30“  a.m.  neutral.  9 a.m.  alkaline.  12'*  30“  p.m.  alkaline.  2'*  30™  p.m. 
slightly  acid. 

February  24. — S'*  30“  a.m.  slightly  acid.  9 a.m.  alkaline.  1 1**  30™  a.m.  alkaline. 

February  25. — S'*  30“ a.m.  slightly  acid.  9 a.m.  neutral.  2 p.m.  alkaline.  4 p.m.  slightly 
acid. 

February  26. — S'*  30™  a.m.  strDngly  acid.  9 a.m.  slightly  acid.  9**  30™  a.m.  alkaline. 

Thus,  just  before  breakfast,  the  urine  was  neutral  twice,  and  alkaline  thrice,  in 
seven  experiments. 

In  the  previous  experiments,  after  honey  had  been  taken  for  breakfast,  the  acidity 
was  seen  not  to  diminish  immediately  after  dinner ; and  the  same  thing  happened 
the  second  day  after  sulphuric  acid  was  taken;  at  5**  30“  p.m.,  immediately  before 
dinner,  the  acidity  was  20‘50  measures  ; nearly  two  hours  afterwards,  at  7*’  10“  p.m., 
the  acidity  had  increased  to  24*26.  At  lO**  30™  p.m.  it  had  diminished  to  6’77-  The 
third  day,  with  the  same  quantity  of  sulphuric  acid,  no  increase  in  the  acidity,  two 
hours  after  food,  was  observed. 

As  no  positive  proof  was  obtained  of  the  influence  of  sulphuric  acid  on  the  acidity 
of  the  urine  by  examining  the  water  passed  at  different  hours,  I next  endeavoured  to 
determine  whether  this  acid  produced  any  effect  on  the  total  amount  of  acidity  of 
the  urine  in  twenty-four  hours. 

It  was  necessary  for  the  purpose  of  comparison,  that  the  total  acidity  of  the  urine 
in  twenty-four  hours,  when  sulphuric  acid  was  not  taken,  should  be  first  known. 
The  breakfast  and  dinner  were  of  meat  and  bread,  coffee,  wine  and  water;  the  same 
for  the  six  days. 


244 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


A.M.  A.M. 

h m h m oz.  Spec.  gr.  Total  carb.  of  soda  required. 

(14.)  Total  quantity  from  7 30  to  7 30=46^  1 022*4=  14'99  grains 

_ [about  8*80  measures  of  acid, 
1 per  1000  grs.  of  urine. 

(15.)  Total  quantity  from  7 30  to  7 30= 35f  1027*1  = 16*87  grains 

=aboutl2*65  acid.perlOOOurine. 

( 1 6.)  Total  quantity  from  7 30  to  7 30 = 44  1 023*8  = 14*31  grains 

=about  8*78acid.perl000urine. 

During  each  of  the  three  following  days,  three  drachms  of  dilute  sulphuric  acid, 
specific  gravity  1*10775  were  taken,  in  three  and  a half  ounces  of  distilled  water;  the 
greater  part  from  9 to  12  a.m. 

A.M.  A.M. 

h m h m oz.  Spec,  gr.  Total  carb.  of  soda  required. 

(17.)  Total  quantity  from  7 30  to  7 30  = 40  1026*2=  17‘59  grains 

_ J ^bout  1 1*88  measures  of  acid. 
1 per  1000  grs.  of  urine. 

(18.)  Total  quantity  from  7 30  to  7 30=54  1020*3=  17*64  grains 

=about  8*82acid.perl000urine. 

(19.)  Thick  from  urates  . . . =40  1028*6  = 25*92  grains 

=aboutl  7*30acid.perl000urine. 

From  the  comparison  of  the  total  amount  of  carbonate  of  soda  required  to  neu- 
tralize the  acidity  of  the  urine,  there  is  no  doubt  that  sulphuric  acid  does  slightly 
increase  the  acidity  of  the  urine.  The  following  day  no  examination  was  made. 

A.M.  A.M. 

h m h m oz.  Spec.gr.  Total  carb.  of  sodarequired. 

Total  quantity  from  7 30  to  7 30  the  next  day =45  1026*7=4*82  grains 

rabout  3*89  measures  of 
=i  acid,  per  1000  grs.  of 
I urine. 

The  conclusions  from  these  experiments  are, — 

I.  As  regards  the  variations  of  the  acidity  of  the  urine  for  three  days  on  mixed 
diet.  The  acidity  soon  after  food  was  found  to  decrease,  and  to  attain  its  lowest 
limit  from  three  to  five  hours  after  breakfast  and  dinner ; sooner,  however,  after 
breakfast  than  after  dinner.  The  acidity  then  gradually  increased,  and  attained  its 
highest  limit  just  before  food.  Once  previous  to  breakfast,  the  urine  was  found  more 
acid  an  hour  before  breakfast  than  it  was  immediately  before  food. 

If  no  food  was  taken  the  acidity  of  the  urine  did  not  decrease,  but  remained  nearly 
the  same  for  twelve  hours.  It  fell  immediately  after  food  was  taken. 

II.  As  to  the  influence  of  animal  and  vegetable  food. 

When  animal  food  only  was  taken,  the  diminution  of  the  acidity  after  food  was 
more  marked  and  more  lasting,  than  when  a mixed  diet  was  taken ; and  the  acidity 
before  food  rose  rather  higher  with  a mixed  diet  than  it  did  with  animal  food. 


OF  THE  URIC  ACID  IN  THE  URINE. 


245 


When  vegetable  food  only  was  taken  the  contrast  with  animal  food  was  very  marked. 
The  urine  did  not  decrease  in  acidity  to  the  same  degree ; though  it  became  neutral, 
it  did  not  become  highly  alkaline.  The  increase  in  the  acidity  of  the  urine  was  by 
no  means  so  marked  as  the  decrease  of  the  alkalescence.  The  acidity  of  the  urine 
was  rather  higher  with  the  vegetable  food  than  it  was  with  animal  food. 

III.  As  to  the  effect  of  dilute  sulphuric  acid. 

Dilute  sulphuric  acid,  taken  in  large  doses,  did  not  produce  any  very  decided  re- 
sults. Nine  drachms  of  dilute  acid  in  three  days  slightly  diminished  the  decrease  in 
the  acidity  of  the  urine  after  food.  The  acidity  before  food  was  very  slightly,  if  at 
all,  increased  thereby. 

When  the  acidity  of  the  whole  quantity  of  water  passed  in  twenty-four  hours,  for 
three  days  when  no  sulphuric  acid  was  taken,  is  compared  with  the  acidity  when 
nine  drachms  of  dilute  sulphuric  acid  were  taken,  the  increase  is  sufficiently  distinct 
to  prove  that  the  acid  does  pass  off  in  the  urine. 

The  result  of  these  experiments  is,  that  the  acidity  of  the  urine  is  always  changing, 
and  that  the  changes  depend  on  the  state  of  the  stomach. 

When  much  acid  is  in  the  stomach,  the  acidity  is  then  diminished.  As  the  acid 
returns  from  the  stomach,  the  acidity  of  the  urine  increases,  and  usually  readies  its 
highest  limit  before  food  is  again  taken. 

Animal  food  causes  a greater  oscillation  in  the  acidity  of  the  urine  than  vegetable 
food  does  ; and  when  no  food  is  taken  the  oscillation  is  very  small. 

The  diurnal  variations  in  the  acidity  of  the  urine  make  it  highly  probable  that 
corresponding  variations  occur  in  the  alkalescence  of  the  blood  ; such  diurnal  varia- 
tions being  produced  by  the  quantity  of  acid  poured  into  the  stomach  for  the  purpose 
of  dissolving  the  food. 

When  the  food  is  irritating,  or  the  stomach  in  an  irritable  state,  much  acid  is 
poured  out,  and  the  effects  on  the  blood  and  urine  are  more  marked  than  they  are 
when  less  acid  is  secreted. 

Dr.  Prout’s  capital  experiment  of  hydrochloric  acid  in  the  stomach  during  diges- 
tion, gives  the  key  to  these  diurnal  variations  of  the  acidity  of  the  urine,  and  may 
lead  to  the  discovery  of  the  diurnal  variations  of  the  alkalescence  of  the  blood. 

Part  II. — On  the  Simultaneous  V aviations  of  the  amount  of  Uric  Acid  and  the  Acidity 

of  the  Urine  in  a Healthy  State. 

The  variations  which  occur  in  the  acidity  of  the  urine  are  of  themselves  of  very 
great  interest,  whether  in  relation  to  health  or  to  disease ; whilst  the  determination 
of  the  amount  of  uric  acid  and  acidity  at  the  same  time  directly  solves  the  question, 
whether  the  acidity  of  the  urine  depends  on  the  uric  acid ; and  thus  alone  can  clear 
views  of  the  causes  of  the  precipitation  of  the  urate  of  ammonia  in  the  urine  be  ob- 
tained. Moreover,  it  is  necessary  to  trace  fully  the  variations  of  the  uric  acid  in 
health  before  deductions  can  safely  be  made  regarding  the  variations  of  the  amount 
of  uric  acid  in  different  diseases. 

2 K 


MUCCCXLIX. 


246 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


The  following  course  was  taken.  A healthy  man  who  took  food  twice  daily,  and 
moderate  exercise  for  three  hours,  was  the  subject  of  the  experiments.  A bottle  con- 
taining 1000  grains  of  water  was  filled  with  urine,  at  a temperature  of  60°.  It  was 
weighed,  and  the  fluid  was  heated  to  120°,  when  a test  alkaline  solution  was  dropped 
from  a graduated  tube,  and  well-stirred,  until  the  urine  became  just  neutral  to  very 
delicate  test-paper. 

The  test  solution  was  prepared  by  taking  dry  and  pure  carbonate  of  soda,  and  dis- 
solving it  in  so  much  water  that  every  measure  of  a graduated  tube  contained  ^^th 
of  a grain  of  carbonate  of  soda  in  solution. 

To  determine  the  amount  of  uric  acid,  upwards  of  2000  grains  of  urine  were  mixed 
with  strong  hydrochloric  acid,  in  the  proportion  of  a drachm  to  the  ounce,  and  left 
to  stand  for  at  least  twenty-four  hours.  The  fluid  was  poured  off,  and  the  residue 
thrown  on  a weighed  filter,  slightly  washed,  and  dried  in  vacuo  over  sulphuric  acid. 

(1.)  Breakfast  on  bread,  coffee,  and  two  eggs,  at  9 a.m.  Dinner  at  7^  p-m.  Fish 
meat,  and  vegetables,  with  water. 


Acidity  per 

Uric  acid 

1000  grs.  of  urine. 

1000  grs.  of 

P.M. 

Spec.  gr. 

measures. 

grain. 

Water  passed  at  2 clear. 

1023*1 

9*77 

0*39 

Water  passed  at  7 clear. 

1026*3 

27-28 

0*048 

Water  passed  at  1 1 cloudy. 

1030*0 

26*21 

0*584 

(2.)  The  following  day,  breakfast  as  yesterday.  Dinner  at  p.m. 

Water  passed  at  2 slightest  cloud. 

1025*4 

4*88 

0*731 

Water  passed  at  6^  clear. 

1026*7 

23*37 

0*14 

Water  passed  at  1 1 clear. 

1025*1 

7-8O 

0*61 

(3.)  Following  day,  breakfast  as  before. 

Dinner  at  6^ 

P.M. 

Water  passed  at  1 clear. 

1025*5 

9*75 

0*53 

Water  passed  at  6^  clear. 

1023*1 

22*48 

0*17 

Water  passed  at  1 1 clear. 

1031*1 

11-64 

0*92 

(4.)  As  yesterday.  Dinner  at  ^ to  6 p.m. 

Water  passed  at  very  thick. 

1027-8 

23*35 

0*53 

Water  passed  at  5f  clear. 

1027-7 

27-24 

0*12 

Water  passed  at  10|  clear. 

1021-0 

13*71 

0*39 

(5.)  As  yesterday.  Dinner  at  7 p-m. 

Water  passed  at  clear. 

1023*1 

17-59 

0*44 

Water  passed  at  7 clear. 

1024*9 

30*24 

0*146 

Water  passed  at  1 1 clear, 

1026*5 

9*74 

0*634 

Average  mean  of  five  days. 

Between  1 and  2 p.m. 

1025*0 

13*07 

0*52 

Between  6 and  7 p-m. 

1025*7 

26*12 

0*12 

Between  10  and  11  p.m. 

1026*7 

13*81 

0*62 

OF  THE  URIC  ACID  IN  THE  URINE. 


247 


From  these  experiments  it  appears  that  the  uric  acid  is  increased  three,  four,  or 
five  times  in  quantity  by  food  ; whilst  the  acidity  is  lessened  to  one-half  what  it  was 
before  food.  The  quantity  of  uric  acid  varies  before  food  from  0’048  gr.  per  1000 
grs.  of  urine,  specific  gravity  1026‘3,  to  0T7  gr.  per  1000  grs.  of  urine,  specific 
gravity  1023T.  After  food  the  quantity  of  uric  acid  varies  from  0’39  gr.  per  1000 
grs.  of  urine,  specific  gravity  102 TO,  to  0‘92gr.  per  1000  grs.  of  urine,  specific  gravity 
103T1.  The  acidity  before  food  varies  from  23‘37  grs.  per  1000  grs.  of  urine,  specific 
gravity  10267j  to  30'24  per  1000  urine,  specific  gravity  1024’9.  After  food  the 
acidity  varies  from  7*80  per  1000  urine,  specific  gravity  1025‘1,  to  26'21  per  1000 
urine,  specific  gravity  1030’0. 

The  uric  acid  was  lowest  when  0’048gr.  per  1000  grs.  of  urine,  specific  gravity 
1026‘3,  was  present,  then  the  acidity  was  27’28  measures.  The  uric  acid  was  highest 
when  there  was  0*92  gr.  per  1000  grs.  of  urine,  specific  gravity  103T1  ; the  acidity 
then  was  IT 64  measures  only. 

(6.)  A child  twenty-three  months  old,  fed  at  1 p.m.  on  bread  with  some  meat  and 
milk,  gave — 

Acidity  per  1000  grs.  Uric  acid  per  1000  grs. 
of  urine.  of  urine. 

Spec.  gr.  measures.  grain. 

Water  passed  at  1 p.m.  1013’6  8'88  0‘27 

Water  passed  at  5 p.m.  1022’0  14’67  0 65 


Both  specimens  deposited  uric  acid  crystals  on  standing;  the  first  in  twenty-four 
hours,  the  last  in  six  hours. 

II.  I next  endeavoured  to  ascertain  what  was  the  influence  of  different  kinds  of 


food  on  the  variations  of  the  uric  acid  and  acidity. 

For  three  successive  days  vegetable  food  alone  was  taken,  with  water  and  coffee. 
Breakfast  at  9^  a.m.  Dinner  at  6^  p.m. 


(7.) 


(8.) 


(9.) 


Acidity  per  1000  grs. 

Uric  acid  per  1000  grs, 

Water  passed  at  1|^  p.m.  A few' 

1 Spec.  gr. 

01  urine. 

measures. 

of  urine, 
grain. 

uric  acid  crystals  formed  on 

>1022-9 

17-60 

0-19 

long  standing 

Water  passed  at  6:^  p.m.  clear  . 

1025-4 

21-45 

0-17 

Water  passed  at  10^  p.m.  clear  . 

1014-8 

12-81 

0-19 

Breakfast  and  dinner  as  yesterday.  Water  at  10|  a.m.  thrown  away,  clear. 

Water  passed  at  2^  p.m.  clear  . 

1021-65 

8-89 

0-565 

Water  passed  at  6^  p.m.  clear  . 

1024-0 

26-36 

0-049 

Water  passed  at  10^  p.m.  clear  . 

1026-2 

3-29 

0-636 

Water  passed  at  6^  a.m.  clear  . 

1024-2 

19-52 

0-665 

Breakfast  and  dinner  the  same  as 

yesterday. 

Water  at  9 thrown  away. 

Water  passed  at  IO^a.m.  thick  on  1 

standing  from  urates  . . .J 

1025-6 

12-67 

1-01 

2 K 2 


248 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


Acidity  per  1000  grs. 

Uric  acid  per  1000  grs 

of  urine. 

of  urine. 

Spec.  gr. 

measures. 

grain. 

Water  passed  at  2|  p.m.  cloudy ' 

j-  1024*5 

alkaline 

0*61 

from  phosphates J 

Water  passed  at  6^  p.m.  clear  . 

1025*9 

26*31 

0*34 

Water  passed  at  10|  p.m.  clear  . 

1014*8 

alkaline 

0*14 

Water  passed  at  6^  a.m.  clear  . 

1014  8 

7-88 

0*049 

When  vegetable  food  only  is  taken  the  same  variations  are  seen  as  when  mixed  diet 
is  eaten.  The  acidity  is  most  before  food.  The  highest  acidity  was  26*36  measures; 
then  the  uric  acid  =0*049  gr.  per  lOOOgrs.  of  urine,  specific  gravity  1024*0.  The 
uric  acid  was  most  after  food;  the  highest  amount  being  1*01  gr.  per  lOOOgrs.  of 
urine,  specific  gravity  1025*6.  The  acidity  then  was  only  12*67  measures  per  1000 
grs.  of  urine.  The  variations  of  the  acidity  in  (9.)  are  very  remarkable. 

For  three  days  in  succession  animal  food  only  was  taken,  meat,  eggs,  cheese,  coffee 
and  water.  Breakfast  at  9 a.m.  Dinner  at  a quarter  to  6 p.m. 


Acidity  per  Uric  acid  per 

1000  grs.  of  urine.  1000 

grs.  of  urine. 

Spec.  gr. 

measures. 

grain. 

(10.) 

Water  passed  at  9 a.m.  clear,  uric  "I 

1023*3 

30*41 

0*69 

acid  crystals  in  four  hours  .J 

Water  passed  at  1 1 a.m.  clear  . 

1015*2 

alkaline 

0*24 

Water  passed  at  1 p.m.  thick  ) 

1022*2 

alkaline 

0*68 

from  phosphates  . . . . J 

Water  passed  at  ^ to  6 p.m.  clear 

1023*9 

20*50 

0*34 

Water  passed  at  10^  p.m.  clear 

1024*1 

11*71 

0*63 

(11.) 

Breakfast  at  9 a.m.  Dinner  at  half-past 

6 P.M.  Food  as  before. 

Water  passed  at  2^  p.m.  clear 

1022*7 

7-82 

0*44 

Water  passed  at  6^  p.m.  clear 

1024*8 

21*46 

0*049 

Water  passed  at  11^  clear 

1029*9 

16*50 

0*77 

(12.) 

Breakfast  at  9 a.m.  Dinner  at  half-past  6 

P.M.  Animal  food  only. 

Water  at 

9 A.M.  thick,  and  was  thrown  away. 

Water  passed  at  2|  p.m.  thick 

1024*7 

16*59 

0*756 

Water  passed  at  6|  p.m.  clear 

1027'1 

24*34 

0*073 

Water  passed  at  ^ to  1 1 p.m.  thick 

1027*8 

18*48 

1*022 

Water  passed  at  4^  a.m.  clear 

1021*4 

16*64 

0*318 

In  these  experiments  also  the  uric  acid  is  increased  after  food,  and  the  acidity  is 
diminished.  The  highest  amount  of  uric  acid  was  1*022  gr.  per  1000  grs.  of  urine, 
specific  gravity  1027*8.  The  acidity  at  the  same  time  was  18‘48  measures.  Previous 
to  food  the  same  day  the  uric  acid  =0*073  gr.  per  1000  grs.  of  urine,  specific  gravity 
1027*1  ; then  the  acidity  =24*34  measures. 

Comparing  the  three  days  on  animal  food  with  the  three  days  on  vegetable  food, 
we  have  the  highest  amount  of  uric  acid  on  the  third  day ; in  the  one  case  =1*022  gr.. 


OF  THE  URIC  ACID  IN  THE  URINE. 


249 


specific  gravity  1027’8,  and  in  the  other  roi  gr.  per  1000  grs.  of  urine,  specific  gravity 
1025'6,  after  dinner  in  the  one  case  and  after  breakfast  in  the  other.  The  lowest 
amount  in  both  was  0'049  gr.  per  1000  urine,  specific  gravity  1024’8  ; and  0‘049  gr., 
specific  gravity  ]024'0,  in  both  instances  before  dinner.  So  that  neither  as  regards 
the  diminution  nor  the  increase  of  the  amount  of  uric  acid  can  any  positive  result 
be  obtained  from  these  experiments  on  the  influence  of  animal  and  vegetable  food. 

The  variations  in  the  acidity  are  not  very  different  on  animal  or  on  vegetable  food; 
the  acidity  rises  higher  when  vegetable  food  is  taken  than  when  animal  food  only 
was  taken. 

I next  endeavoured,  if  possible,  to  determine  the  effect  of  exercise.  No  food  was 
taken  from  dinner  on  the  previous  day  to  dinner  this  day  at  a quarter  to  six ; both 
meals  consisted  of  mixed  diet  of  bread,  meat  and  potatoes.  The  exercise  was  mo- 
derate between  three  and  six. 

No  water  was  passed  from  11  the  previous  night  to  6 a.m. 


Acidity  per  1000  grs. 
of  urine. 

Uric  acid  per  1000  grs. 
of  urine. 

(13.)  Water  passed  at  6 A.M.  clear  . 

Spec.  gr. 

1026*7 

measures. 

13*63 

grain. 

0*63 

Water  passed  at  1 1 a.m.  clear  . 

1024*3 

19*52 

0*63 

Water  passed  at  ^ to  6 p.m.  . . 

1027*9 

12*65 

0*73 

Water  passed  at  1 1 p.m.  clear  . 

1021*0 

alkaline 

0*49 

Water  passed  at  6 a.m.  clear 

1022*3 

22*49 

0*58 

(14.)  Nothing  was  taken  from  dinner 

on  the  previous  day  until  5^ 

P.M.  this  day. 

Strong  exercise  was  taken  from  2^  to  5^  p.m.  Pulse  always  above  100. 

At  nine  urine 

clear  and  thrown  away. 

Acidity  per  1000  grs. 
of  urine. 

Uric  acid  per  1000  grs. 
of  urine. 

Spec.  gr. 

Water  passed  at  1 p.m,  few  uric  acid  crystals  1 022*5 

measures. 

19*56 

grain. 

0-344 

Water  passed  at  5|  p.m.  clear  . . . . 

1025*2 

25*36 

0*268 

Water  passed  at  10^  p.m.  very  thick,  some 
uric  acid  crystals 

1 1030*0 

19*41 

1*286 

Water  passed  at  1^  a.m.  very  thick,  some 
uric  acid  crystals 

1 1027*1 

17*52 

0*924 

Water  passed  at  7 a.m.  very  thick,  some 
crystals  of  uric  acid 

j 1025*5 

33*14 

0*878 

(15.)  Nothing  was  taken  from  dinner 

on  the  previous  day  until 

ten  minutes  after 

five  this  day.  Moderate  exercise  was  taken  from  2 

to  5 P.M. 

Acidity  per  1000  grs. 
of  urine. 

Uric  acid  per  1000  grs. 
of  urine. 

h m 

Water  passed  at  6 10  a.m.  clear  . 

Spec.  gr. 

. 1025*7 

measures. 

15*59 

grain . 

0-098 

Water  passed  at  1 1 20  a.m.  thick 

. 1024*8 

13*96 

0*61 

Water  passed  at  5 10  p.m.  thick. 

. 1028*3 

14*90 

0*52 

Water  passed  at  1 1 p.m.  clear  . 

. 1031*1 

2*85 

0*87 

Water  passed  at  5 40  a.m.  clear  . 

. 1026*9 

10*71 

0*12 

250 


DR.  BENCE  JONES  ON  THE  DEPOSIT 


Hence  no  conclusion  can  be  drawn  regarding  the  effect  of  exercise  on  the  excretion 
of  uric  acid.  The  influence  of  food  lasts  so  long  in  increasing  the  amount  of  urates 
that  no  results  regarding  exercise  could  be  obtained;  experiment  (14)  is  no  positive 
proof  of  the  increase  or  diminution  of  the  uric  acid  by  exercise. 

The  three  following  days  the  total  amount  of  uric  acid  excreted  in  twenty-four 
hours  was  determined.  The  breakfast  and  dinner  were  of  meat  and  bread,  coffee, 
wine  and  water : the  same  each  day. 

Uric  acid  per 

Uric  acid.  Quantity  1000  grs. 

gr.  Spec,  gr.  of  urine,  of  urine. 

(16.)  Total  quantity  from  7^  30”“  A.M.  to  7^  30“  a.m.=5’9  1022'4=46^I  0*29  gr. 

(17.)  The  following  day.  Total  quantity  . . =7’7  ]027'l=35f§  0-48 

(18.)  The  following  day.  Total  quantity  . . =7*0  1023'8  = 44§  0-36 

In  the  course  of  the  following  three  dqys  nine  drachms  of  dilute  sulphuric  acid 
were  taken.  The  food  was  the  same  as  before. 

Uric  acid  per 
Quantity  1000  grs. 
Spec.  gr.  of  urine,  of  urine. 

1026-2  = 40g  0-41  gr. 

1020*3  = 54g  0-27 

1028'6=:40g  0-56 


( 1 9.)  Total  quantity  from  7^‘  30“  a.m.  to  7^  a.m. 

(20.)  The  following  day,  total  quantity  . . 

(21.)  Thick  from  urates,  the  following  day,  quantity 

The  conclusions  from  these  experiments  are, — 

I.  As  regards  the  variations  of  the  acidity  and  uric  acid  when  mixed  diet  was  taken. 


Uric  acid. 

gr- 
.=7-3 
. = 6-5 
:9-9 


Per  1000  grs.  of  urine. 

Spec.  gr. 

0-048  gr. 

1026-3 

0-17  gr. 

1023-1 

0-39  gr. 

1021-0 

0*92  gr. 

1031-1 

. 23-37  measures 

1026-7 

. 30-24  measures 

1024-9 

7-30  measures 

1025-1 

. 26-21  measures 

1030-0 

The  uric  acid  varies  before  food  from 
The  uric  acid  varies  before  food  to  . 

It  varies  after  food  from  .... 

It  varies  after  food  to  . ... 

The  acidity  varies  before  food  from  . 

The  acidity  varies  before  food  to  . . 

It  varies  after  food  from  .... 

It  varies  after  food  to 

II.  As  to  the  influence  of  vegetable  and  animal  food  and  exercise. 

When  vegetable  food  only  was  taken  the  uric  acid  was  highest  after  food. 

Per  1000  grs.  of  urine. 

Being  at  most  TOl  gr. 

Then  the  acidity  was 12‘67  measures 

The  uric  acid  was  least  before  food,  being  at  least  0'049  gr. 

Then  the  acidity  was  26'36  measures 

When  animal  food  only  was  taken  the  uric  acid  was  highest  after  food. 

Being  at  most T022  gr. 

Then  the  acidity  was 18'48  measures 

The  lowest  uric  acid  was  before  food,  being  at  least  0-049  gr. 

Then  the  acidity  was 21-46  measures. 


Spec.  gr. 

1025-6 


1024-0 


1027-8 


1024-8 


OF  THE  URATES  IN  THE  URINE. 


251 


There  is  no  great  difference  between  animal  and  vegetable  food  ; and  no  proof  was 
obtained  of  the  influence  of  exercise  on  the  excretion  of  uric  acid. 

From  the  experiments  on  the  total  amount  of  uric  acid  excreted  in  twenty-four 
hours,  it  appears  as  though  the  deficiency  one  day  was  followed  by  an  excess  the  fol- 
lowing day. 

The  result  of  these  experiments  is,  that  there  is  no  relation  between  the  acidity  of 
the  urine  and  the  amount  of  uric  acid  in  it.  The  urine  that  was  most  acid  contained 
least  uric  acid.  That  which  contained  most  uric  acid  was  not  highly  acid. 

All  food  causes  an  increase  in  the  amount  of  uric  acid  in  the  urine,  and  there  is  no 
decided  difference  between  vegetable  and  animal  food,  either  as  to  the  increase  or 
diminution  of  the  amount  of  uric  acid  in  the  urine. 

These  experiments  also  show  the  variations  of  the  acidity  of  the  urine  which  the 
food  produces.  They  were  made  four  months  previous  to  the  experiments  in  the  first 
part  of  this  paper,  which  were  made  in  October.  Those  here  given  were  made  in 
June. 


On  the  Deposit  of  Urates  in  the  Urine. 

That  the  amount  of  urates  in  the  urine  is  not  the  only  cause  of  their  deposit,  the 
following  experiments  are  sufficient  to  prove : — 


Water  passed  at 

h 

5 

m Spec,  gr, 

5 p.M.  1024‘9 

Acidity  and  uric  acid 
per  1000  grs.  of  urine, 
grain. 

18-53  measures  0-22  No  deposit. 

Water  passed  at 

7 

35  1029-2 

15-54 

0*29 

Thickish  from  urates. 

Water  passed  at 

10 

5 1027-2 

alkaline 

0-33 

No  deposit. 

Another  day  at 

5 

50  p.M.  1024*4 

21-47 

0-07 

No  deposit. 

7 

55  1029-6 

15-57 

0-31 

Thickish  from  urates. 

10 

45  1029-8 

alkaline 

0-90 

No  deposit. 

Another  day  at 

10 

p.M.  1030-6 

alkaline 

0-76 

No  deposit. 

The  same  is  well 

seen  in  (15.). 

at 

5 

10  p.m.  1028-3 

14-90 

0-52 

Thick  from  urates. 

11 

1031-1 

2-85 

0-87 

Clear. 

The  influence  of  temperature  is  always  shown  in  the  precipitation  of  urates  taking 
place  on  the  cooling  of  the  urine.  The  low  temperature  of  the  night  frequently  will 
cause  a deposit  which  would  not  form  during  the  day. 

The  influence  of  the  acidity  of  the  urine  on  the  deposit  can  always  be  shown  by 
adding  any  acid  to  the  urine  passed  soon  after  food.  Two  portions  being  taken,  and 
the  one  being  made  more  acid  than  the  other,  will  show  a difference  in  the  time  or 
degree  of  deposit. 

The  influence  of  water  in  preventing  a deposit  is  shown,  by  adding  distilled  water 
to  urine  which  would  give  a precipitate.  Evaporation  under  the  air-pump  takes  away 


252 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


water,  increases  the  proportion  of  urate  of  ammonia  to  the  water,  at  the  same  time 
it  increases  the  acid  reaction  of  the  urine.  By  carrying  the  evaporation  far  enough, 
deposit  of  urate  of  ammonia  always  occurs. 

The  influence  of  strong  light  is  seen  in  its  occasionally  causing  a deposit  only  on 
the  side  of  the  glass  nearest  to  the  light.  Brisk  agitation  also  sometimes  will  hasten 
or  cause  a deposit  of  urate  of  ammonia. 

From  the  above  experiments  and  observations,  it  follows  that  the  deposit  of  urate 
of  ammonia  does  not  generally  depend  only  on  the  proportion  of  the  water  to  the 
urate  of  ammonia  being  relatively  or  positively  diminished.  Nor  does  it  depend 
solely  on  the  degree  of  acidity  of  the  urine ; but  it  results  from  the  simultaneous 
action  of  botli  causes,  aided  always  by  a low  temperature. 

Alkaline  urine  will  hold  in  solution  a great  excess  of  urate  of  ammonia,  and  very 
feebly  acid  urine  will  dissolve  much  more  urate  of  ammonia  than  very  highly  acid 
urine.  But  highly  acid  urine  will  give  no  precipitate  of  urate  of  ammonia  if  only  a 
very  small  quantity  of  that  substance  is  present  in  it. 

The  deposit  of  urate  of  ammonia  is  therefore  the  result  of  the  united  action  of  three 
causes : — 

1.  Decrease  of  temperature. 

2.  Increased  proportion  of  urate  of  ammonia  to  the  water,  positively  or  relatively. 

3.  Increased  acidity  of  the  urine. 

Sometimes  one  cause,  sometimes  the  other,  is  the  most  efficient ; but  they  are  all 
usually  concerned  in  causing  the  deposit  of  urate  of  ammonia. 

Part  III. — Variations  of  the  Sulphates  in  the  Urine  in  the  healthy  state,  and  on  the 

influence  of  Sulphuric  Acid,  Sulphur  and  the  Sulphates,  on  the  amount  of  the  Sulphates 

in  the  Urine. 

Before  tracing  the  variations  of  the  sulphates  in  disease,  it  is  necessary  to  deter- 
mine their  limits  in  the  healthy  state ; and  it  is  also  desirable  to  know  as  far  as  pos- 
sible what  the  effect  of  medicinal  substances  on  their  amount  may  be.  Thus  the  in- 
fluence of  sulphuric  acid,  of  the  sulphates,  and  of  sulphur  on  the  amount  of  sulphuric 
acid  excreted,  must  be  determined  before  the  results  of  diseased  action  can  be  esti- 
mated. By  this  means  alone  can  it  be  shown  what  is  the  effect  of  ordinary  causes 
or  remedies,  and  what  is  the  effect  of  disease. 

A healthy  man  taking  food  twice  daily,  with  moderate  exercise  for  three  hours,  was 
the  subject  of  the  following  experiments.  The  specific  gravity  of  the  urine  was  first 
taken.  To  a weighed  quantity,  usually  about  500  grains,  chloride  of  barium  in  excess 
was  added,  and  then  a few  drops  of  nitric  acid.  Heat  was  then  applied  until  the 
liquid  boiled  briskly,  when  the  sulphate  of  baryta  was  filtered,  well-washed,  and 
ignited  in  a platinum  crucible,  after  which  it  was  weighed. 

By  this  method  very  accurate  results  could  be  obtained. 


OF  THE  SULPHATES  IN  THE  URINE. 


253 


(1.)  Breakfast  on  bread  and  cocoa  at  8|  a.m.  Dinner  on  meat,  potatoes,  bread 
and  water  at  p.m. 

Sulphate  of  baryta  per 
1000  grs.  of  urine. 
Spec.  gr.  grains. 


Water  passed  at  3 p.m.  filtered 1028‘2  9' 16 

Water  passed  at  6^  clear 1027*0  8*41 

Water  passed  at  10^  filtered 1033*9  15*23 


(2.)  Food  as  before.  Between  3 and  7 p-m.  strong  exercise  was  taken.  Dinner  at  7 p.m. 


Water  passed  at  7 p-m.  clear 

1025-3 

7*07 

Water  passed  at  1 1 filtered 

1030*8 

11*53 

Water  passed  at  1 a.m.  clear 

1025*1 

6*47 

(3.)  Breakfast  at  9 a.m.  as  before.  Dinner  at  6^  p.m. 

Water  passed  at  3^  p.m.  filtered 

1026*8 

7*96 

Water  passed  at  6^  clear 

1027*0 

7*36 

Water  passed  at  10^  

1031*0 

10*63 

(4.)  Breakfast  at  9 a.m.  as  before.  Water  passed  at  10  a.m.  thrown 

away.  Dinner 

6^  P.M. 

Water  passed  at  12|^p.m.  filtered 

1025*6 

7*52 

Water  passed  at  3^  

1025*9 

7*95 

Water  passed  at  6:^  

1026*0 

8.25 

Water  passed  at  10^  clear 

1029*3 

9*45 

(5.)  Breakfast  at  9 a.m.  as  before.  Dinner  at  5^  p.m. 

Water  passed  at  1 p.m.  clear 

1024*0 

6*48 

Water  passed  at  3|^  

1023*6 

6*03 

Water  passed  at  5|  

1027*6 

8*56 

Water  passed  at  9^  filtered 

1030*8 

12*43 

Average  mean  of  five  days  after  dinner,  with  perfect  rest 

1031*1 

11*85 

Average  mean  of  five  days  just  before  dinner,  after  exercise 

1026*5 

7*93 

Average  of  four  days,  longer  before  dinner 

1026*1 

7*77 

From  these  experiments  it  appears  that  the  sulphuric  acid  is  much  increased  in  the 
water  passed  after  food,  the  quantity  varying — 

From  15*23  grs.  of  sulphate  of  baryta  per  1000  grs.  of  urine,  specific  gravity  1033*9 
To  9*49  grs.  of  sulphate  of  baryta  per  1000  grs.  of  urine,  specific  gravity  1029*3 
The  mean  of  all  the  experiments  after  food  being  11*85  per  1000  urine,  specific 
gravity  1031*1. 

The  quantity  of  sulphuric  acid  is  much  less  in  the  water  secreted  a long  time  after 
food,  varying — 

From  8*56  grs.  of  sulphate  of  baryta  per  1000  grs.  of  urine,  specific  gravity  1027*6 
To  7*07  grs.  of  sulphate  of  baryta  per  1000  grs.  of  urine,  specific  gravity  1025*3 
The  mean  of  all  the  experiments  before  food  being  7*93  grs.  per  1000  grs.  of  urine, 
specific  gravity  1026*5. 


2 L 


MDCCCXLIX. 


254 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


(6.)  A child  two  years  old,  fed  on  bread  with  some  meat  and  milk,  gave  in  the 
water  passed  during  the  night,  acid,  specific  gravity  =1014'6,  sulphate  of  baryta  4‘66 
grs.  per  1000  grs.  of  urine, 

(7.)  On  the  same  food  another  night,  specific  gravity  =1013‘5,  sulphate  of  baryta 
3‘88  grs.  per  1000  grs.  of  urine. 

II.  I next  endeavoured  to  ascertain  by  what  causes  the  variations  were  produced. 
And  first  (a.)  with  regard  to  food  of  different  kinds.  For  three  consecutive  days  bread 
alone,  with  a little  rice  and  water  and  tea,  was  taken  at  the  same  hours  as  food  had 
been  taken  in  the  previous  experiments. 

Spec.  gr.  Sulphate  of  baryta. 

(8.)  Water  passed  at  6 p.m.  clear  1019'46  5’31  grs.  per  1000  grs.  of  urine. 

Water  passed  at  1 1 filtered  1025’30  10’57 

(9.)  Breakfast  and  dinner  as  on  the  previous  day.  Distilled  water  only  was  taken. 

Water  passed  at  3 p.m.  filtered  1025*88  8*03  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 . . 1026*00  7'31 

Water  passed  at  1 1 . . 1030*40  13*21 

(10.)  Breakfast  and  dinner  as  on  the  previous  day.  Spring  water  drunk. 

Water  passed  at  3 p.m.  . . 1027*56  9*53  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 . . 1028*58  9*46  per  1000  urine. 

Water  passed  at  1 1 . . . 1031*86  13*68 

(11.)  Animal  food  only  was  taken  for  three  days  with  tea  and  water.  Breakfast 
at  9 A.M. : animal  food  and  tea.  Dinner  at  6 p.m.  : animal  food  and  water,  1 p.m. 
water  was  thrown  away. 

Water  passed  at  6 p.m.  clear  1023*02  6*86  grs.  per  1000  grs.  of  urine. 

Water  passed  at  1 1 . . . 1021*10  7’69 

(12.)  Breakfast  and  dinner  as  on  the  previous  day.  Distilled  water  only  taken. 

Water  passed  at  3 p.m.  . . 1021*30  6*30  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 ...  1025*52  9*12 

Water  passed  at  1 1 . . . 1023*60  10*19 

(13.)  Breakfast  and  dinner  as  on  the  previous  day.  Common  water  taken. 

Water  passed  at  3 p.m.  filtered  1023*92  8*36  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 clear  1025*44  9*30 

Water  passed  at  1 1 filtered  1026*24  11*14 

From  the  comparison  of  these  numbers  with  the  average  previously  given,  no  de- 
duction can  be  drawn  as  to  the  peculiar  influence  of  animal  or  vegetable  food  on  the 
amount  of  the  sulphates  in  the  urine.  After  either  animal  or  vegetable  food  the  sul- 
phates are  increased. 

II.  (b.)  I then  tried  to  determine  the  effect  of  exercise. 

(14.)  Nothing  whatever  was  taken  from  dinner  the  preceding  day,  which  consisted 
of  meat  only,  until  dinner  this  day,  which  consisted  of  bread,  tea,  and  an  egg.  The 


OF  THE  SULPHATES  IN  THE  URINE. 


255 


water  made  at  a quarter  to  2 p.m.  was  thrown  away.  From  four  to  a quarter  past  6 
moderate  and  sometimes  strong  exercise  was  taken. 


Water  passed  at  4 p.m.  filtered 

Spec.  gr. 

. 1029*52 

Sulphate  of  baryta. 

8*76  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6^  . . 

. 1031*18 

r 11*26 

1 11*23 

Water  passed  at  10:j  . . 

. 1029*04 

12*34 

(15.)  Nothing  whatever  was  taken  from  dinner  the  preceding  day,  which  consisted 
of  bread  and  meat,  until  dinner  this  day.  Water  made  at  1 p.m.  thrown  away.  From 

3 to  6,  at  times,  gentle  exercise  was  taken. 

Water  passed  at  3 p.m.  filtered 

Spec.  gr. 

. 1024*78 

Sulphate  of  baryta. 

5*48  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 ... 

. 1026*88 

7-03 

Water  passed  at  1 1 ... 

. 1027-50 

9*34 

(16.)  Nothing  was  taken  from 

dinner  the  preceding  day  to  dinner  this  day.  The 

water  passed  at  1 p.m.  was  thrown 

away.  From  3 to  6 strong  exercise  was  taken. 

Water  passed  at  3 p.m.  filtered 

Spec.  gr. 

. 1021*20 

Sulphate  of  baryta. 

3*27  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 ... 

. 1019*10 

r 3*55 

1 3*47 

Water  passed  at  10^  clear  . 

. 1027-00 

8*00 

From  these  numbers  it  appears  that  food  has  more  influence  on  the  sulphates 
than  exercise  has.  (14.)  shows  that  exercise  has  a decided  effect  in  increasing  the 
sulphates.  The  increase  is  less  marked  in  (15.) ; the  same  is  seen  in  (16.)  to  a much 
less  degree  in  consequence  of  the  diminution  of  the  specific  gravity. 

III.  The  influence  of  different  medicinal  substances  admits  of  a clearer  demonstra- 
tion. 


(a.)  (17.)  Breakfast  as  before  at  9 a.m.  Dinner  at  p.m.  At  1 p.m.  thirteen  drops 
of  sulphuric  acid,  specific  gravity  =1786*4,  equivalent  to  above  1:^3  of  dilute  sulphuric 
acid,  were  taken  in  water. 


Spec.  gr. 

Sulphate  of  baryta. 

Water  passed  at  1 p.m.  clear . . 

1027*6 

7*51  grs.  per  1000  grs.  of  urine. 

Water  passed  at  3 ... 

1028*7 

9*75 

Water  passed  at  6^  ... 

1027-9 

10*36 

Water  passed  at  10  ... 

1031*5 

12*15 

(18.)  Breakfast  as  before.  Dinner 

at  6 P.M. 

At  1 P.M.  rather  less  sulphuric  acid 

was  taken. 

Spec.  gr. 

Sulphate  of  baryta. 

Water  passed  at  12^  P.M.  . . . 

1022*5 

4*07  gi'S.  per  1000  grs.  of  urine. 

Water  passed  at  3 .... 

1022*2 

5*28 

Water  passed  at  6 .... 

1021*9 

6*19 

Water  passed  at  10^  .... 

1028*1 

2 L 2 

10*66 

256 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


(19.)  Breakfast  as  before, 
acid  as  before. 

Dinner  at  6 p.m. 

At  1 P.M.  thirteen  drops  of  sulphuric 

Water  passed  at  1 p.m. 

Spec.  gr. 

. . . 1018*8 

Sulphate  of  baryta. 

3*48  grs.  per  1000  grs.  of  urine. 

Water  passed  at  ^ to  3 

. . . 1012*6 

2*13 

Water  passed  at  6 

. . . 10177 

4*09 

Water  passed  at  10 

. . . 1026*2 

11*43 

(20.)  Breakfast  as  before, 
acid  taken  as  before. 

Dinner  at  6 p.m. 

At  1 P.M.  twenty  drops  of  sulphuric 

Water  passed  at  1 p.m. 

. . . 1022*8 

4*83  grs.  per  1000  grs.  of  urine. 

Water  passed  at  3 

. . . 1019*9 

4*99 

Water  passed  at  6 

. . . 1022*2 

6*79 

Water  passed  at  lOj 

. . . 1021*3 

9*52 

(21.)  Breakfast  as  before. 

Dinner  as  before. 

No  sulphuric  acid  taken. 

Water  passed  at  3 p.m. 

. . . 1025*0 

7*08  grs.  per  1000  grs.  of  urine. 

Water  passed  at  6 

. . . 1023*9 

5*88 

Water  passed  at  10^ 

. . . 1029*4 

10*79 

From  experiment  (17-)  it  seemed  that  the  sulphates  were  slightly  increased  by  the 
sulphuric  acid  which  was  taken.  The  other  experiments  hardly  confirm  this  deduc- 
tion, and  on  this  account  I tried  whether  a course  of  sulphuric  acid  would  give  more 
marked  results. 

(22.)  After  four  days  in  which  dilute  sulphuric  acid,  specific  gravity  1115*3,  was 


taken ; three  drachms  the  first  day  and  two  drachms  the  three  following  days. 


Breakfast  and  dinner  the  day  after  the 

course  of 

sulphuric  acid  were  the  same  as  in 

the  previous  experiments. 

Water  passed  at  1 p.m. 

clear . . 

Spec.  gr. 

Sulphate  of  baryta. 

1027*4 

7*51  grs.  per  1000  grs.  of  urine. 

Water  passed  at  3 

filtered  . 

1025*4 

8*73 

Water  passed  at  6 

clear  . . 

1026*5 

8*72 

Water  passed  at  10^ 

filtered  . 

1030*2 

11*99 

(23.)  No  sulphuric  acid  was  taken  on  the  day  of  experiment  (22.).  For  the  next 
three  days  three  drachms  of  dilute  sulphuric  acid  were  taken  the  first  day,  two 
drachms  the  second,  and  three  drachms  the  third  day. 

The  following  day  (seventeen  drachms  of  dilute  sulphuric  acid  having  been  taken 
in  the  eight  previous  days)  the  breakfast  and  dinner  were  as  before. 


Spec,  gr. 

Sulphate  of  baryta. 

Water  passed  at 

1 

p.m.  filtered  . 

1026*0 

7‘37  grs.  per  1000  grs.  of  urine. 

Water  passed  at 

3 

* 

1025*9 

7*22 

Water  passed  at 

6— 

clear . . 

1023*3 

5*43 

Water  passed  at 

10 

filtered  . 

1028*1 

10*66 

OF  THE  SULPHATES  IN  THE  URINE. 


257 


From  these  experiments  it  does  not  appear  at  all  certain  that  dilute  sulphuric  acid 
does  pass  off  in  the  urine.  The  question  being  still  undecided,  the  amount  of  sul- 
phates in  the  whole  quantity  of  water  passed  in  twenty-four  hours,  for  three  success- 
ive days,  when  no  sulphuric  acid  had  been  taken,  was  compared  with  the  amount 
of  sulphates  in  the  whole  quantity  of  water  passed  in  twenty-four  hours,  for  the 
three  succeeding  days,  when  sulphuric  acid  had  been  taken.  The  breakfast  and 
dinner  were  the  same  for  the  six  days. 


(24.)  Total  quantity  of  water  passed  in^ 

twenty-four  hours,  from  7 a.m.  >1024  2 
to  7 a.m.  =37i  ounces,  filtered-^ 


Spec.  gr.  Sulphate  of  baryta. 

7*75  grs.  per  1000  grs.  of  urine. 
66 


9-18 
20 


r 9’] 

(25.)  The  following  day =42  ounces,  clear  1023*4  -j 

L 9 

(26.)  The  following  day  =34  ounces,  7.33 

filtered j 


During  each  of  the  three  following  days  half  an  ounce  of  dilute  sulphuric  acid, 
specific  gravity  =1108*4,  was  taken  in  distilled  water,  the  greater  part  from  9 to 
12  A.M. 


Spec.  gr. 

(27.)  Total  quantity  46  ounces,  filtered  1024*2 
(28.)  The  following  day  42^  ounces,  clear  1024*0 
(29.)  The  following  day  43  ounces,  clear  1025*4 


Sulphate  of  baryta. 

r 9*56  grs.  per  1000  grs.  of  urine. 
1 9*64 

r 11*66 

I 11*64 
r 13*10 
1 12*81 


By  comparing  these  experiments,  it  is  certain  that  dilute  sulphuric  acid,  taken  in 
very  large  quantity,  does  cause  an  increase  in  the  amount  of  sulphates  passing  olF  in 
the  urine. 


III.  (b.)  (30.)  Breakfast  at  9 a.m.  Dinner  at  6 p.m.  : the  water  made  at  1 1 a.m.  was 
thrown  away,  and  61^  grains  of  dry  sulphur  in  fine  powder  were  taken. 


Spec.  gr.  Sulphate  of  baryta. 


Water  passed  at 

1 P.M.  filtered  . 

1020*2 

5*44 

Water  passed  at 

6 .... 

1023*1 

7*99 

Water  passed  at 

11  .... 

1027‘6 

13*37 

(31.)  Experiment  r 

epeated. 

Water  passed  at 

1 P.M.  clear . . 

1012*2 

2*89 

Water  passed  at 

6 .... 

1020*7 

6*20 

Water  passed  at 

1 1 filtered  . 

1026*2 

11*76 

(32.)  Experiment  r 

epeated. 

Water  passed  at 

1 P.M.  clear  . . 

1014*6 

4*19 

Water  passed  at 

6 .... 

1022*5 

10*26 

Water  passed  at 

11  filtered  . . 

1025*4 

15*05 

258 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


(33.)  Experiment  repeated. 

Spec.  gr. 

Water  passed  at  1 p.m.  clear  1018‘9 
Water  passed  at  3 . lOlS’O 

Water  passed  at  6 . 1025’6 

Water  passed  at  11  filtered  1027'9 

(34.)  Experiment  repeated. 

Water  passed  at  1 p.m.  filtered  1023'0 
Water  passed  at  3 clear  . . lost 

Water  passed  at  6 clear  . 1020’7 

Water  passed  at  1 1 filtered  . 1028'8 


61^  grains  of  dry  sulphur  taken  each  day. 
Average  of  five  days  after") 
dinner  and  rest  . . . . J 

Immediately  before  dinner  "I 


1027-1 


after  exercise 


1022'5 


Sulphate  of  baryta. 

6‘81  grs.  per  1000  grs.  of  urine. 

6- 52 
11-89 
14'74 

7'99 

7- 11 
15-15 


14-01  grs.  per  1000  grs.  of  urine. 
8-69 


Comparing  this  average  of  experiments  30,  31,  32,  33,  34,  with  the  average  of  ex- 
periments 1,  2,  3,  4,  5,  it  is  seen  that  the  sulphates  are  positively  increased  in  the 
urine  when  sulphur  is  taken  into  the  stomach. 

III.  (c.)  (35.)  Breakfast  9 a.m.  Dinner  at  6|^p.m.  : at  1 p.m.  123^  grains  of  dry 
sulphate  of  potash  were  taken  in  1^  ounce  of  distilled  water.  It  did  not  act  on  the 
bowels. 

Spec.  gr.  Sulphate  of  baryta. 

Water  passed  at  1 p.m.  clear  1017-7  3-03  grs.  per  1000  grs.  of  urine. 


Water  passed  at  3 ... 

IOI6-7 

3-00 

Water  passed  at  6^  ... 

1020-8 

6-65 

Water  passed  at  10^  . . . 

1026-0 

12-18 

(36.)  The  same  quantity  of  sulphate  of  potash  taken  at 

Water  passed  at  1 p.m.  clear 

1020-2 

3-17 

Water  passed  at  3^  . . 

1024-0 

8-74 

Water  passed  at  6|^  . . 

1024-2 

12-51 

Water  passed  at  1 0|^  . . 

1032-4 

20-49 

(37.)  Experiment  repeated. 

Water  passed  at  1 p.m.  clear 

1021-6 

3-17 

Water  passed  at  3 . . 

1021-4 

4-98 

Water  passed  at  6 . . 

1024-0 

9-04 

Water  passed  at  10^  filtered 

1030-8 

15-72 

Hence  123  grains  of  sulphate  of  potash  began  to  increase  the  amount  of  sulphates 
in  the  urine  from  four  to  six  hours  after  they  were  taken ; and  the  effect  was  strongly 
marked  from  seven  to  twelve  hours  afterwards. 

In  my  next  paper,  on  the  sulphates  in  the  urine  in  disease,  many  instances  will  be 


OF  THE  SULPHATES  IN  THE  URINE. - 


259 


g-iven  of  an  increase  in  the  amount  of  sulphates  in  consequence  of  sulphate  of  magnesia 
having  been  taken  in  doses  of  about  2 drachms.  The  highest  instances  were — 

Spec.  gr.  Sulphate  of  baryta. 

In  one  case  urine  . . 1028’0  contained  15-89  grs.  per  1000  grs.  of  urine. 

In  another  case  urine  . 1024-3  contained  22-55  grs. 

The  conclusions  from  these  experiments  are, — 

I.  That  the  sulphate  of  baryta  varies  soon  after  food  from  15-23  grs.  per  1000  grs. 
of  urine,  specific  gravity  1033-9,  to  9-45  grs.  per  1000  grs.  of  urine,  specific  gravity 
1029-3.  It  varies  long  after  food  from  8-56  grs.  per  1000  grs.  of  urine,  specific  gravity 
1027-6,  to  7‘07  grs.  per  1000  grs.  of  urine,  specific  gravity  1025-3. 

II.  As  to  the  causes  of  variation — (a)  as  regards  food ; {b)  as  regards  exercise. 

{a)  Food,  whether  animal  or  vegetable,  causes  an  increase  in  the  quantity  of  sul- 
phate of  baryta  precipitated,  but  the  difference  between  animal  and  vegetable  food  is 
not  well-marked. 

{b)  Exercise  appears  slightly  to  increase  the  amount  of  sulphates  in  the  urine,  but 
the  increase  is  not  so  marked  as  it  is  after  food. 

III.  As  to  the  effect  of  medicines  on  the  sulphates, — (a)  sulphuric  acid ; {b)  sul- 
phur; (c)  sulphates. 

{a)  Thirteen  drops  of  strong  sulphuric  acid  in  one  of  three  experiments  increased 
the  sulphates  in  the  urine.  Twenty  drops  of  the  same  acid  gave  no  positive  proof. 

Seventeen  drachms  of  dilute  sulphuric  acid,  taken  in  eight  days,  gave  no  positive 
proof  of  an  increase  of  sulphates  in  the  urine  on  the  ninth  day. 

But  when  the  whole  quantity  of  urine  passed  in  twenty-four  hours  for  three  suc- 
cessive days,  when  no  sulphuric  acid  had  been  taken,  was  compared  with  the  whole 
quantity  passed  in  twenty-four  hours,  when  half  an  ounce  of  dilute  sulphuric  acid 
was  taken,  then  for  three  successive  days  that  the  experiment  was  made,  the  increase 
of  sulphates  was  most  marked.  And  from  this  it  is  certain,  that  when  a large  quan- 
tity of  dilute  sulphuric  acid  is  taken  the  sulphates  are  increased  in  the  urine.  When 
small  quantities  of  sulphuric  acid  are  taken  the  effect  on  the  sulphates  in  the  urine 
is  not  detectable. 

{b)  61 J grains  of  dry  sulphur,  taken  for  five  days,  gave  an  average  amount  of  sul- 
phates in  the  urine,  both  before  and  after  food,  higher  than  when  no  sulphur  was 
taken.  But  with  this  dose  the  increase,  though  decided,  was  not  considerable. 

(c)  123^  grains  of  sulphate  of  potash  produced  a marked  increase  from  two  to 
four  hours  afterwards.  In  seven  hours  the  increase  was  more  marked.  Sulphate 
of  magnesia  had  a similar  effect.  The  increase  in  the  sulphates  in  the  urine  was 
much  more  evident  than  when  sulphur  or  sulphuric  acid  were  taken. 

The  result  of  these  experiments  is — 

1st.  That  the  sulphates  in  the  urine  are  much  increased  by  food,  whether  it  be 
vegetable  or  animal. 


260  DR.  BENCE  JONES  ON  THE  VARIATIONS  OF  THE  SULPHATES  IN  THE  URINE. 

2nd.  Exercise  does  not  cause  a very  marked  increase  in  the  sulphates. 

3rd.  Sulphuric  acid  when  taken  in  large  quantity  increases  the  sulphates  in  the 
urine.  In  small  quantity,  even  when  long  continued,  no  effect  is  manifest. 

4th.  Sulphur  when  taken  does  increase  the  sulphates  in  the  urine. 

.5th.  Sulphate  of  potash  and  sulphate  of  magnesia  produce  the  most  marked 
increase  of  the  sulphates  in  the  urine. 


[ 261  ] 


XIV.  Appendix  to  a paper  on  the  Variations  of  the  Acidity  of  the  Urine  in  the  state 

of  Health. 

By  Henry  Bence  Jones,  M.D.,M.A.  Cantab. ,F.R.S., Physician  to  St.  Georges  Hospital. 


Received  May  7, — Read  May  24,  1849. 


On  the  Influence  of  Caustic  Potash,  Tartaric  Acid,  and  Tartrate  of  Potash  on  the 

Acidity  of  the  Urine. 

In  a paper  on  the  variations  of  the  acidity  of  the  urine  in  the  state  of  health,  I have, 
in  the  third  section,  given  the  effect  of  dilute  sulphuric  acid  ; in  this  Appendix  I pur- 
pose to  show  the  influence  of  other  medicines  on  the  variations  of  the  acidity  of  the 
urine. 

III.  (&.)  The  effect  of  caustic  potash  on  the  acidity  of  the  urine  was  examined. 

The  caustic  potash  of  pharmacy  varying  much  in  its  specific  gravity  from  1060 
downwards,  and  in  the  proportion  of  carbonate  of  potash  which  it  contains,  some 
caustic  potash  perfectly  free  from  carbonate,  and  of  specific  gravity  1072,  containing, 
by  Dr.  Hofmann’s  analysis,  from  6*20  to  6'29  per  cent,  of  potash,  was  used  for  the 
following  experiments.  It  was  taken  in  distilled  water. 

The  day  before  the  alkali  was  begun  the  variations  of  the  acidity  of  the  urine  were 
first  determined  for  the  purpose  of  comparison. 

The  first  day  two  drachms  and  a half  of  caustic  potash  were  taken  ; the  same 
quantity  the  second  day,  and  the  third  day  three  drachms  were  taken.  Thus  eight 
drachms  were  taken  in  three  days ; and  the  following  day,  when  no  caustic  potash 
was  taken,  the  variations  of  the  acidity  of  the  urine  were  again  determined  for  the 
purpose  of  further  comparison. 

(20.)  The  day  previous  to  the  alkali.  Breakfast  on  eggs,  meat,  coffee  and  bread,  at 
8**  5“  A.M.  Dinner  on  mixed  diet  at  6*“  p.m.  Water  passed  at  f 1 S'”  a.m.  was  thrown  away. 


h 

m 

Spec.  gr. 

Acidity  per  1000  grains  of  urine. 

Appearance. 

Water  passed  at  8 

5 a.m. 

= 1023-2 

= -f  25-41  measures. 

Thick  from  urates. 

Water  passed  at  9 

30 

= 1022-8 

= +12-61 

Thick  from  urates. 

Water  passed  at  10 

45 

= 1024-1 

= - 4-88 

Clear. 

Water  passed  at  11 

35 

= 1027-0 

= -13-63 

Clear. 

Water  passed  at  12 

35  P.M. 

= 1026-5 

= - 3-89 

Clear. 

Water  passed  at  2 

30 

= 1025-0 

= +14-72 

Clear. 

Water  passed  at  4 

15 

= 1024-4 

= +20-49 

Clear. 

Water  passed  at  6 

0 

= 1026-6 

= +31-17 

Thick  from  urates. 

Water  passed  at  9 

0 

= 1028-6 

= +18-47 

Clear. 

Water  passed  at  11 

0 

= 1028-0 

= -11-67 

Clear. 

From  this  it  appears  that  the  variations  are  nearly  alike  to  those  which  were 

2 M 


MDCCCXLIX. 


262 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


observed  six  months  previously ; and  it  is  worth  noting  that  for  six  weeks  before 
this  experiment  very  little  walking  exercise  was  taken. 

(21.)  The  following  day  breakfast  was  as  before,  at  10“  a.m.  Dinner  at  O'*  p.m. 
One  drachm  and  a half  of  liquor  potassse  was  taken  in  distilled  water  between  1 1’*  a.m. 
and  1^  P.M.,  and  another  drachm  between  S’*  and  S’*  S0“  p.m.,  both  in  as  little  water  as 
possible. 


h m 

Spec.  gr.  Acidity  per  1000  grs.  of  urine.  Appearance. 

Water  passed  at  7 0 a.m. 

= 1019-0 

= + 14-71  measures. 

Clear. 

Water  passed  at  8 10 

= 1026-1 

= +20-46 

Thick  from  urates. 

Water  passed  at  9 30 

= 1025-0 

= +12-68 

Clear. 

Water  passed  at  11  0 

= 1025-8 

0 

Clear. 

Water  passed  at  1 0 p.m. 

= 1025-6 

= - 6-82 

Clear. 

Water  passed  at  3 0 

= 1024-1 

= + 10-74 

Clear. 

Water  passed  at  3 40 

= 1022-0 

= + 9-78 

Clear. 

Water  passed  at  6 0 

= 1019-2 

= +10-78 

Thick  from  urates. 

Water  passed  at  9 0 

= 1032-0 

-=  + 11-62 

Clear. 

Water  passed  at  11  15 

= 1028-7 

= -28-19 

Thick  from  phosphates. 

Water  passed  at  6 30  a.m. 

= 1024-3 

= + 1-95 

Clear. 

Water  passed  at  7 40  lost. 

(22.)  The  following  day. 

Breakfast  at  S’*  40“  a.m.  Dinner  at  O’*  p.m.  Liquor  potassse 

a drachm  and  a-half  from 

10’*  to  10’*  30*” 

‘ A.M.  and  one  drachm  at  3 p.m.  In  as  little 

distilled  water  as  possible. 

Water  passed  at  8 40 

= 1024-4 

= + 12-69  measures. 

Clear. 

Water  passed  at  9 50 

= 1024-6 

= +11-71 

Thick  from  urates. 

Water  passed  at  10  50 

= 1021-5 

= + 1-95 

Clear. 

Water  passed  at  11  55 

= 1024-5 

0 

Clear. 

Water  passed  at  2 45  p.m. 

= 1025-3 

= - 1-95 

Clear. 

Water  passed  at  4 10 

= 1025-7 

= + 9-74 

Clear. 

Water  passed  at  6 0 

= 1027-1 

= + 14-59 

Thick  from  urates. 

Water  passed  at  8 40 

= 1033-3 

= +14-51 

Thick  from  urates. 

Water  passed  at  11  30 

= 1031-5 

= + 9-70 

Thick  from  urates. 

(23.)  The  following  day. 

Breakfast  at 

S’*  10“  A.M.  Dinner  at  O’*  30“  P.M.  A drachm 

and  a-half  of  liquor  potassse  was  taken 

at  O’*  30“a.m.,  a drachm  at  10’*  a.m.,  and  a 

drachm  at  11’*  15“  a.m. 

Water  passed  at  7 0 a.m. 

= 1020-2 

= + 11-76  measures. 

Clear. 

Water  passed  at  8 10 

= 1017-3 

= + 3-93 

Clear. 

Water  passed  at  9 20 

= 1020-0 

= + 4-94 

Thick  from  urates. 

Water  passed  at  10  30 

= 1010-0 

= - 3-96 

Clear. 

Water  passed  at  11  15 

= 1019-7 

= -11-76 

Clear. 

Water  passed  at  12  5 p.m. 

= 1019-8 

= -19-61 

Clear. 

Water  passed  at  12  35 

= 1022-6 

= -18-58 

Clear. 

W’^ater  passed  at  2 45 

= 1022-6 

= + 2-93 

Clear. 

Water  passed  at  3 45 

= 1024-0 

= + 8-79 

Clear. 

Water  passed  at  5 20 

= 1024-4 

= +10-73 

Thick  from  urates. 

Water  passed  at  6 30 

= 1025-3 

= +11-70 

Thick  from  urates. 

OF  THE  ACIDITY  OF  THE  URINE. 


263 


h 

m 

Spec.  gr. 

Acidity  per  1000  grs.  of  urine. 

Appearance. 

Water  passed  at  9 

10  P.M. 

= 1029*4 

= + 4*85  measures. 

Thick  from  urates. 

W’^ater  passed  at  11 

45 

= 1030*6 

= -16*50 

Clear. 

Water  passed  at  6 

55  A.M. 

= 1020*3 

= - 0*98 

Clear. 

Water  passed  at  8 

15 

= 1023*2 

= - 2*93 

Clear. 

(24.)  The  following  day.  Breakfast  at  S'*  15“  a.m.  Dinner  at  O'*  30“  p.m.  Food  as 
before.  No  alkali  was  taken. 

Water  passed  at  10 

0 

= 1025*0 

= — 4*88  measures. 

Clear. 

Water  passed  at  11 

25 

= 1025*1 

= -18*53 

Iridescent  scum. 

Water  passed  at  12 

45  P.M. 

= 1025*0 

= - 9*75 

Clear. 

Water  passed  at  2 

50 

= 1024*2 

= + 11-71 

Clear. 

Water  passed  at  4 

15 

= 1025*0 

= + 15*60 

Clear. 

Water  passed  at  6 

30 

= 1027*0 

= + 21*42 

Thick  from  urates. 

Water  passed  at  10 

45 

= 1030*2 

= + 10*67 

Thick  from  urates. 

Water  passed  at  6 

30  a.m. 

= 1014*5 

= + 4*92 

Clear. 

Water  passed  at  8 

10 

= 1022*2 

= -t-  9*88 

Clear. 

The  result  of  these  experiments  is  easily  seen  in  Table  XXL  It  follows  therefrom 
that  liquor  potassse,  taken  in  large  doses,  produces  a decided  effect  in  diminishing 
the  acidity  of  the  urine. 

It  by  no  means  renders  the  urine  constantly  alkaline,  and  its  effect  on  the  urine 
seems  rapidly  to  pass  away.  Notwithstanding  the  large  quantity  of  liquor  potassee 
taken,  the  influence  of  food  appears  very  evident ; before  each  meal  the  acidity  was 
highest ; after  each  meal  the  alkalescence  was  greatest. 

The  acidity  of  1000  grains  of  urine  was  rarely  more  than  sufficient  to  neutralize 
one  grain  of  dry  and  pure  carbonate  of  soda ; and  the  alkalescence  was  more  than 
equal  to  a grain  and  a half  of  carbonate  of  soda  in  1000  grains  of  urine. 

The  conclusion  from  these  experiments  is,  that  an  ounce  of  liquor  potassse  taken 
in  three  days  does  not  counteract  or  conceal  the  influence  of  the  stomach  on  the  re- 
action of  the  urine. 

III.  (c.)  The  effect  of  tartaric  acid  on  the  acidity  of  the  urine  was  then  examined. 
Some  splendid  crystals  of  tartaric  acid  were  given  to  me  by  Mr.  Morson.  These 
were  dried,  reduced  to  a fine  powder  and  heated  in  a water -bath  until  they  ceased  to 
lose  weight ; a weighed  quantity  was  dissolved  in  distilled  water. 

(25.)  The  first  day  for  comparison  no  tartaric  acid  was  taken.  Breakfast  at  S'*  45“a.m. 
Dinner  at  6^  10"*  p.m.  Mixed  diet. 


Water  passed  at 
Water  passed  at 
Water  passed  at 
Water  passed  at 
Water  passed  at 
Water  passed  at 
Water  passed  at 


h m Spec.  gr.  Acidity  per  1000  grs.  of  urine.  Appearance. 

7 45  A.M.  thrown  away. 


8 

45 

= 1025*4 

9 

45 

= 1025*0 

10 

45 

= 1022*7 

12 

45  P.M. 

= 1027*5 

2 

55 

= 1027*1 

6 

10 

= 1025*7 

= -1- 19’50  measures.  Thick  from  urates. 
= -1- 13*65  Thick  from  urates. 

= — 2*93  Clear. 


= — 8*75  Clear. 

= -f-  7-79  Clear. 

= -f  26*32  Thick  from  urates. 


2 M 2 


264 


DR.  BENCE  .TONES  ON  THE  VARIATIONS 


h m 

Water  passed  at  8 35  p.m. 
Water  passed  at  10  30 
Water  passed  at  6 40  a.m. 


Spec.  gr.  Acidity  per  1000 
= 1032-3  =+19-37 

= 1031-9  =+14-53 

= 1023-8  = + 19-53 


grs.  of  urine.  Appearance, 

measures.  Thick  from  urates. 

Thick  from  urates. 
Clear. 


For  the  three  following  days  tartaric  acid  was  taken.  The  first  day  forty-two 
grains  of  dry,  pure  tartaric  acid,  in  two  ounces  of  distilled  water,  at  1 P 40*"  a.m. 
Forty-two  grains  more  at  12'’  40"’  p.m.  In  all,  eighty-four  grains.  It  did  not  act  on 
the  bowels  as  an  aperient,  but  it  caused  pain  in  the  bowels  from  about  three  hours 
after  it  was  taken.  It  produced  no  pain  when  first  taken  into  the  stomach. 

(26.)  Breakfast  as  before,  at  8'’  lO*"  a.m.  Dinner  as  before,  at  6'’  30'"  p.m,,  eighty- 
four  grains  of  tartaric  acid  being  taken. 


Water  passed  at 

8 10  a.m. 

= 1025-3 

= + 24-38  measures. 

Thick  from  urates. 

Water  passed  at 

10  0 

= 1026-2 

= +13-64 

Thick  from  urates. 

Water  passed  at 

11  15 

= 1029-1 

= - 7-77 

Clear. 

Water  passed  at 

12  55  P.M. 

= 1027-9 

0 

Clear. 

Water  passed  at 

2 30 

= 1027-1 

= +23-36 

Clear. 

Water  passed  at 

4 40 

= 1027-4 

= +25-30 

Cloudy  urates. 

Water  passed  at 

6 30 

= 1030-4 

= +32-99 

Thick  from  urates. 

Water  passed  at 

8 40 

= 1033-1 

= +36-79 

Thick  from  urates. 

Water  passed  at 

11  40 

= 1033-0 

= + 7-74 

Thick  from  urates. 

Water  passed  at 

6 50  a.m. 

= 1022-2 

= + 17-60 

Clear. 

(2/.)  The  following  day. 

Breakfast  as  before,  at  8'’  10'"  a.m. 

Dinner  at  6'’  Sh*"  p.m. 

^artaric  acid,  fifty-four  grains  dry  and 

pure,  in  two  ounces 

of  distilled  water,  at 

B A.M. ; fifty-four  grains,  in  two  ounces  of  water,  at  12'’  15'"  p.m.  ; in  all  108  grains, 
"his  day  the  dinner  was  more  and  longer  than  usual. 

Water  passed  at 

8 10 

= 1026-0 

= + 23-33  measures. 

Thick  from  urates. 

Water  passed  at 

9 30 

= 1021-5 

= +14-68 

Thick  from  urates. 

Water  passed  at 

10  10 

= 1020-6 

0 

Clear. 

Water  passed  at 

11  0 

= 1025-8 

= - 9-74 

Clear. 

Water  passed  at 

12  15  P.M. 

= 1026-4 

0 

Clear. 

Water  passed  at 

2 15 

= 1026-2 

= +16-56 

Clear. 

Water  passed  at 

3 15 

= 1025-0 

= +23-41 

Clear. 

Water  passed  at 

5 30 

= 1024-8 

= +25-37 

Clear. 

Water  passed  at 

6 35 

= 1027*0 

= +31*15 

Clear. 

Water  passed  at 

11  30 

= 1034-0 

= + 19-43 

Thick  from  urates. 

AVater  passed  at 

6 50  a.m. 

= 1025-4 

= +16*58 

Clear. 

(28.)  The  following  day.  Breakfast  as  before,  at  8'’  15"’  a.m.  Dinner  moderate,  mixed 
diet,  at  6'’  50"’  p.m.  At  1 1'’  a.m.,  tartaric  acid,  fifty-four  grains  in  two  ounces  of  water. 
At  11'’  40’"  A.M.  fifty-four  grains  of  acid  ; at  12'’  40“  p.m.  fifty-four  grains;  in  all  162 
grains.  No  pain  in  the  abdomen  until  3^  p.m.,  then  much  pain  for  an  hour.  Less 
pain  for  another  hour,  then  all  the  pain  went  away.  No  action  of  the  acid  on  the 
bowels. 


OF  THE  ACIDITY  OF  THE  URINE. 


205 


h m 

Spec.  gr.  Acidity  per  1000  grs.  of  urine. 

Appearance. 

Water  passed  at 

8 15  A.M. 

= 1026-0 

= -1-21-44  measures. 

Thick  from  urates. 

Water  passed  at 

9 50 

= 1024-2 

= -f  0-97 

Clear. 

Water  passed  at 

10  40 

= 1024-9 

= —28-29 

Thick  from  phosphates. 

Water  passed  at 

11  40 

= 1024-4 

= -23-42 

Thick  from  phosphates. 

Water  passed  at 

12  40  P.M. 

= 1023-7 

= + 3-90 

Clear. 

Water  passed  at 

1 15 

= 1023-5 

= + 9-77 

Clear. 

Water  passed  at 

2 25 

= 1024-7 

= -8  22-44 

Clear. 

Water  passed  at 

3 15 

= 1023-4 

= -8  24-42 

Clear. 

Water  passed  at 

5 5 

= 1019-4 

= + 26-48 

Clear. 

Water  passed  at 

6 50 

= 1025-3 

= + 29-26 

Clear. 

Water  passed  at 

11  35 

= 1030-6 

= +17-46 

Thick  from  urates. 

Water  passed  at 

6 20  a.m. 

= 1025-0 

= + 5-85 

Clear. 

Water  passed  at 

8 15 

(29.)  The  following  day. 

Breakfast  at  8^ 

IS'”  A.M.  Dinner  at  6^p.m.  Food  as  befor 

No  tartaric  acid 

was  taken. 

Water  passed  at 

8 15 

= 1026-4 

= +21-43  measures. 

Thick  from  urates. 

Water  passed  at 

10  15 

= 1025-4 

= + 6-82 

Clear. 

Water  passed  at 

11  20 

= 1024-7 

= -13-66 

Clear. 

Water  passed  at 

12  35  P.M. 

= 1025-5 

= - 7-80 

Clear. 

Water  passed  at 

2 40 

= 1026-0 

= +14-61 

Clear. 

Water  passed  at 

6 20 

= 1028-6 

= +26-23 

Clear. 

Water  passed  at 

11  25 

= 1031-0 

= + 5-81 

Thick  from  urates. 

Water  passed  at 

6 45  A.M. 

= 1024-6 

= + 10-72 

Clear. 

Water  passed  at 

8 10 

= 1025-9 

= + 14-62 

Clear. 

The  result  of  these  experiments  is  easily  seen  in  Plate  XXII.  It  follows  that  tartaric 
acid  in  large  doses  does  produce  a decided  effect  on  the  acidity  of  the  urine ; but  it 
did  not  render  the  urine  constantly  acid  during  the  three  days  that  the  experiment 
lasted. 

The  first  day  on  which  the  acid  was  taken,  the  urine  was  much  more  concentrated 
than  on  the  two  other  days,  and  hence  the  effect  of  the  smaller  dose  of  acid  appears 
more  evident  than  the  larger. 

The  influence  of  the  state  of  the  stomach  is  very  apparent.  Before  each  meal  the 
acidity  is  greatest.  After  food,  notwithstanding  the  tartaric  acid,  the  acidity  is 
diminished. 

The  alkalescence  of  the  urine  was  rarely  so  much  as  to  equal  one  grain  of  carbo- 
nate of  soda  in  1000  grains  of  urine  ; whilst  the  acidity  of  1000  grains  of  urine  for  the 
most  part  required  about  two  grains  of  carbonate  of  soda  to  make  its  reaction  neutral. 

The  conclusion  from  these  experiments  is,  that  354  grains  of  dry  and  pure  tartaric 
acid,  taken  in  three  days,  increases  the  acidity  of  the  urine  ; but  in  that  time  it  does 
not  render  the  effect  of  the  stomach  on  the  reaction  of  the  urine  less  apparent  than 
when  no  acid  was  taken. 

III.  {d.)  The  effect  of  tartrate  of  potash  on  the  acidity  of  the  urine  was  then  ex- 
amined. Some  well-crystallized  tartrate  of  potash  was  dried,  reduced  to  a fine  pow- 
der and  dissolved  in  distilled  water.  The  solution  was  neutral  to  test-paper. 


266 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


(30.)  The  first  day,  for  comparison,  no  tartrate  of  potash  was  taken.  Breakfast  at 
8''  1 5“  A.M.  Dinner  at  6**  p.m.  Mixed  diet.  Water  passed  at  6^  45“  a.m.  thrown  away. 


h m 

Water  passed  at  8 25  a.m. 
Water  passed  at  9 40 
Water  passed  at  10  50 
Water  passed  at  12  56  p.m. 
Water  passed  at  3 10 
Water  passed  at  5 55 
Water  passed  at  10  40 
Water  passed  at  6 15  a.m. 


Spec.  gr. 

Acidity  per  1000  grs.  of  urine. 

= 1023-3 

= 4-  21-49  measures. 

= 1024-4 

= + 17-57 

= 1027-0 

= - 9-73 

= 1027-2 

= + 6-81 

= 1025-7 

= +23-39 

= 1028-2 

= +28-20 

= 1034-4 

= +18-36 

= 1025-4 

= +16-58 

Appearance. 

Clear. 

Clear. 

Clear. 

Clear. 

Clear. 

Clear. 

Thick  from  urates. 
Clear. 


For  the  following-  days  tartrate  of  potash  was  taken.  The  first  day  two  drachms 
of  dry  and  pure  tartrate  of  potash  were  taken,  dissolved  in  two  ounces  of  distilled 
water,  at  O’*  a.m.  The  same  quantity  was  taken  at  10**  25“  a.m.  ; and  one  drachm  of 
tartrate  of  potash  was  taken  in  one  ounce  of  water  at  2^  30“  p.m.  This  last,  on  an 
empty  stomach,  caused  slight  nausea  for  twenty  minutes.  In  all,  then,  on  this  day 
five  drachms  of  tartrate  of  potash  were  taken  in  five  ounces  of  distilled  water.  The 
bowels  were  not  acted  on  by  the  saline. 

(31.)  The  breakfast  was  at  S’*  10“  a.m.  Dinner  at  6’*  30”*  p.m.  Mixed  diet. 


Water  passed  at 

8 10 

= 1026-4 

= + 23-38  measures. 

Thick  from  urates. 

Water  passed  at 

9 30 

= 1022-4 

= + 2-93 

Clear. 

Water  passed  at 

10  30 

= 1024-5 

= -29-29 

Cloudy  from  phosphates. 

Water  passed  at 

11  30 

= 1023-7 

= -31-16 

Cloudy  from  phosphates. 

Water  passed  at 

12  20  P.M. 

= 1021-4 

= -14-68 

Slight  cloudiness  from  phosphates. 

Water  passed  at 

2 25 

= 1025-8 

= + 4-87 

Clear. 

Water  passed  at 

4 5 

= 1027-5 

= - 4-86 

Clear. 

Water  passed  at 

6 30 

= 1033-3 

= +24-19 

Clear. 

Water  passed  at 

8 55 

= 1036-5 

= +21-22 

Thick  from  urates. 

Water  passed  at 

10  45 

= 1028-4 

= -39-86 

Thick  from  phosphates. 

Water  passed  at 

6 30  a.m. 

= 1027-0 

= -14-60 

Cloudy  from  phosphates. 

(32.)  The  following  day.  Breakfast  as  before,  at  8’*  10“*  a.m.  Dinner  at  O’*  45"*  p.m. 
Three  drachms  of  tartrate  of  potash  in  four  ounces  of  water,  at  2^*  10*”  p.m.  caused 
slight  nausea,  and  no  action  of  the  bowels. 


Water  passed  at  8 10 

= 1030-2 

= — 9-70  measures. 

Clear. 

Water  passed  at  9 30 

= 1026-2 

= -19-49 

Thick  from  phosphates. 

Water  passed  at  11 

= 1024-9 

= -27-31 

Thick  from  phosphates. 

Water  passed  at  12  30  p.m. 

= 1027-9 

= - 5-83 

Cloudy  from  phosphates. 

Water  passed  at  2 10 

= 1028-8 

= +23-32 

Clear. 

Water  passed  at  3 30 

= 1025-7 

= -18-52 

Clear. 

Water  passed  at  5 10 

= 1025-1 

= -10-73 

Clear. 

Water  passed  at  6 45 

= 1031-0 

= +19-39 

Clear. 

Water  passed  at  9 

= 1034-1 

CO 

1 

11 

Clear. 

Water  passed  at  10  45 

= 1026-3 

= -37-02 

Thick  from  phosphates. 

Water  passed  at  6 20  a.m, 

. = 1027-8 

= - 4-86 

Clear. 

OF  THE  ACIDITY  OF  THE  URINE. 


267 


(33.)  The  following  day.  Breakfast  as  before,  at  8 a.m.  Dinner  at  6^*  45™  p.m.  Two 
drachms  of  tartrate  of  potash  in  four  ounces  of  distilled  water,  at  2*^  45™  p.m.  caused 
the  slightest  nausea  and  no  action  of  the  bowels. 


h 

m 

Spec.  gr. 

Acidity  per  1000  grs.  of  urine. 

Appearance. 

Water  passed  at 

8 

= 1031-8 

= + 4-84  measures. 

Clear. 

Water  passed  at 

9 

45 

= 1026-7 

= -22-42 

Thick  from  phosphates. 

W’'ater  passed  at 

11 

45 

= 1025-9 

= -28-26 

Thick  from  phosphates. 

Water  passed  at 

1 

P.M. 

= 1027-4 

= + 4-85 

Clear. 

Water  passed  at 

2 

45 

= 1030-9 

= +29-10 

Cloudy  from  urates. 

Water  passed  at 

3 

20 

= 1026-6 

= - 7-79 

Clear. 

Water  passed  at 

3 

50 

= 1026-2 

= -17-54 

Clear. 

Water  passed  at 

4 

50 

= 1027-8 

= +11-67 

Clear. 

Water  passed  at 

6 

45 

= 1032-8 

= +23-23 

Clear. 

Water  passed  at 

9 

25 

= 1036-5 

= + 9-64 

Very  thick  from  urates. 

Water  passed  at 

11 

45 

= 1029-6 

= -33-99 

Very  thick  from  phosphates. 

Water  passed  at 

5 

55  A.M. 

= 1021-5 

= -14-68 

Cloudy  from  phosphates. 

(34.)  The  following  day.  Breakfast  as  before,  at  8^  5™  a.m.  Dinner  at  6^  55^  p.m.  At 
oh  30™  P.M.  three  ounces  of  distilled  water  without  any  tartrate  of  potash  were  taken. 


Water  passed  at 

8 

5 

= 1028-5 

= + 8-75  measures. 

Clear. 

Water  passed  at 

9 

20 

= 1021-3 

= - 5-87 

Clear. 

Water  passed  at 

11 

= 1020-0 

= -31-37 

Thick  from  phosphates. 

Water  passed  at 

12 

45  P.M. 

= 1025-4 

= -20-48 

Cloudy  from  phosphates. 

Water  passed  at 

2 

30 

= 1026-3 

= + 9-74 

Clear. 

Water  passed  at 

3 

40 

= 1024-3 

= +23-43 

Clear. 

Water  passed  at 

5 

25 

= 1026-3 

= +26-30 

Clear. 

Water  passed  at 

6 

55 

= 1028-4 

= +31-11 

Clear. 

Water  passed  at 

9 

5 

= 1032-2 

= +27-12 

Thick  from  urates. 

Water  passed  at 

11 

25 

= 1033-2 

= +23-22 

Thick  from  urates. 

Water  passed  at 

6 

20  A.M. 

= 1026-5 

= - 0-97 

Cloudy  from  phosphates. 

Water  passed  at 

8 

5 

= 1026-5 

= + 17-53 

Clear. 

(35.)  Breakfast  the  following  day  at  8^*  5™  A.M.  Dinner  at  G'' 30™  p.m.  At2*^30™p.M. 
thirty  grains  of  pure  fused  nitrate  of  potash  were  taken  dissolved  in  three  ounces  of 
distilled  water. 


Water  passed  at 

9 

35 

= 1027-1 

= + 8-76  measures. 

Clear. 

Water  passed  at 

11 

20 

= 1028-9 

= -22*35 

Thick  from  phosphates 

Water  passed  at 

12 

40  P.M. 

= 1028-0 

= - 2-92 

Clear. 

Water  passed  at 

2 

30 

= 1025-8 

= +21-44 

Clear. 

Water  passed  at 

3 

10 

= 1024-6 

= +23-42 

Clear. 

Water  passed  at 

3 

55 

= 1025-4 

= +27-30 

Clear. 

Water  passed  at 

5 

= 1027-2 

= +31-15 

Clear. 

Water  passed  at 

6 

30 

= 1029-5 

= +33-02 

Clear. 

It  follows  from  these  experiments,  which  are  easily  seen  in  Plate  XXIII.,  that  the 
influence  of  tartrate  of  potash  is  most  decided.  In  five-and-thirty  minutes  after  two 


268 


DR.  BENCE  JONES  ON  THE  VARIATIONS 


drachms  of  tartrate  of  potash  were  taken,  dissolved  in  four  ounces  of  distilled  water, 
the  urine  was  found  alkaline,  but  in  two  hours  the  urine  was  again  acid : the  first 
effect  on  the  urine  had  ceased  to  be  very  evident.  That  this  was  not  caused  by  mere 
irritation  of  the  stomach  is  seen  by  nitre  and  distilled  water  producing  no  similar 
effect.  The  influence  of  the  tartrate  of  potash  became  again  evident  after  the  next 
meal,  when  the  decrease  in  the  acidity  of  the  urine  was  much  greater  than  when  no 
tartrate  of  potash  was  taken. 

From  the  high  specific  gravity  of  the  urine  after  the  tartrate,  it  is  probable  that 
undecomposed  tartrate  of  potash  passes  off  in  the  urine,  and  from  the  height  to 
which  the  acidity  rises  when  the  medicine  is  taken,  it  seems  possible  that  the  tartaric 
acid  is  not  decomposed  but  separated  from  the  base  in  transitu ; but  on  this  point 
further  experiments  are  requisite. 

When  much  larger  doses  of  tartrate  of  potash  were  taken,  the  rise  and  fall  of  the 
acidity  of  the  urine  before  and  after  food  were  still  distinctly  evident. 

The  conclusions  from  these  experiments  regarding  the  effect  of  medicines  on  the 
acidity  of  the  urine  are — 

(b.)  That  liquor  potassse  taken  in  large  doses  does  lessen  the  acidity  of  the  urine. 
One  ounce  of  liquor  potassae  taken  in  three  days  hindered  the  acidity  of  the  urine  from 
rising  before  food  to  the  height  it  otherwise  would  have  done,  but  it  by  no  means 
made  the  urine  constantly  alkaline,  nor  did  it  hinder  the  variations  produced  by  the 
state  of  the  stomach  from  being  very  evident. 

(c.)  That  tartaric  acid  in  large  doses  does  increase  the  acidity  of  the  urine. 
354 -grains  of  dry  pure  tartaric  acid,  dissolved  in  water,  taken  in  three  days,  caused 
the  acidity  of  the  urine  before  food  to  rise  considerably  higher  than  it  otherwise 
would  have  done ; but  this  quantity  of  acid  was  not  sufficient  to  hinder  the  urine 
passed  a few  hours  after  food  from  being  alkaline.  This  quantity  of  tartaric  acid 
therefore  in  this  time  does  not  produce  so  much  effect  on  the  reaction  of  the  urine 
as  the  stomach  does. 

(d.)  That  tartrate  of  potash  in  large  doses  produces  the  most  marked  effect  on  the 
alkalescence  of  the  urine.  120  grains  of  pure  dry  tartrate  of  potash  dissolved  in  four 
ounces  of  distilled  water  made  the  urine  alkaline  in  thirty-five  minutes.  In  two 
hours  the  alkalescence  had  disappeared,  but  after  the  next  meal  the  effect  of  the 
tartrate  of  potash  was  again  apparent. 

Ten  drachms  of  tartrate  of  potash  taken  in  three  days  produced  but  little,  if  any, 
effect  on  the  acidity  of  the  urine  after  it  had  been  omitted  for  twenty-four  hours. 


OF  THE  ACIDITY  OF  THE  URINE. 


269 


Description  of  the  Plates. 

PLATE  XVI. 

The  variations  of  the  acidity  of  the  urine  during  seventy-two  hours  when  a mixed 
diet  was  taken. 


PLATE  XVII. 

The  comparison  of  the  variations  of  the  acidity  of  the  urine  on  two  mornings,  on 
the  first  of  which  no  breakfast  was  taken,  and  on  the  second  a mixed  diet. 

PLATE  XVIII. 

The  variations  of  the  acidity  of  the  urine  during  seventy-two  hours  when  animal 
food  only  was  taken. 

PLATE  XIX. 

The  variations  of  the  acidity  of  the  urine  during  seventy-two  hours  when  vegetable 
food  only  was  taken ; at  the  end  of  that  time  animal  food  only  was  taken,  and  for 
eight  hours  afterwards  the  acidity  of  the  urine  is  given  in  this  Plate. 

PLATE  XX. 

The  variations  of  the  acidity  of  the  urine  during  seventy-two  hours  when  nine 
drachms  of  dilute  sulphuric  acid  and  mixed  diet  were  taken. 

PLATE  XXL 

The  variations  of  the  acidity  of  the  urine  during  120  hours.  In  the  first  twenty- 
four  hours  no  liquor  potassse  was  taken  ; in  the  following  seventy-two  hours  upwards 
of  an  ounce  of  liquor  potassse  was  taken  with  a mixed  diet,  and  for  the  last  twenty- 
four  hours  no  liquor  potassse  was  taken. 

PLATE  XXII. 

The  variations  of  the  acidity  of  the  urine  during  120 
four  hours  no  tartaric  acid  was  taken ; in  the  following 
of  dry  and  pure  tartaric  acid  were  taken  with  a mixed 
four  hours  no  tartaric  acid  was  taken. 

PLATE  XXIII. 

The  variations  of  the  acidity  of  the  urine  during  132  hours.  For  the  first  twenty- 

2 N 


hours.  For  the  first  twenty- 
seventy-two  hours  354  grains 
diet,  and  for  the  last  twenty- 


MDCCCXLIX. 


270  DR.  BENCE  JONES  ON  THE  VARIATIONS  OF  THE  ACIDITY  OF  THE  URINE. 

four  hours  no  tartrate  of  potash  was  taken ; in  the  following  seventy-two  hours  ten 
drachms  of  tartrate  of  potash  were  taken  with  a mixed  diet,  and  for  the  next  twenty- 
four  hours  no  tartrate  of  potash  was  taken,  and  in  the  last  twelve  hours  thirty  grains 
of  nitre  were  taken. 

PLATE  XXIV. 

The  comparison  of  the  variations  of  the  acidity  of  the  urine  when  different  diets 
were  taken. 


PLATE  XXV. 

The  comparison  of  the  variations  of  the  acidity  of  the  urine  when  sulphuric  acid, 
liquor  potassse,  tartaric  acid  and  tartrate  of  potash,  and  a mixed  diet  only,  were 
taken. 


J dasirf.h^  . 


I 


) 


1 


J'HasuTc.UOv 


T7te  of'  t/ie  oA  f/i^  l/rino’  (Ary-m^  Jeyen^'  livo  J/royy'.)', 

ivhen  Am'yyiyzZ  -food  or/Zy  M^a^r  tyaZcoJV. 


\ 


I 

I’ 


•I 


J 

I 


ji|v 

— 

:^§' 

•HSi 5S^ 

f^'v) 



^ 

,>\ts. 



e^«rv 

■^5i  • 

K 

— 

■~tf^ 

Jtf  T^ 

^ 

^ g 

^'iPs  " : 
T “ 

_ S -* 

— ' ~ 



1 — 

_| |i 

X 

s 

■ .X  ■■^. 

■•  ■.  ■ •';• 

POr'W  ^ 

s 

'S-K 

^ 

^ 

•M 

— 



ff 

■S 

^ 

gj 



fs,\5 

~ ■ h'  ^ 

1^ 

— |y 

^ 

J>5S 

%— 



^ 

? 

J 

s 

V 

<s 

"^^  Sv 

m 

•s, 



s. 

— 1 

^ 

2 



^ 1^  V ^ 



> 

^ 

> 

1^  — 

1 

, 5 

h 



^ 



s 

V 



^ 

tv  ^ 

s,'^ 

?%■ 

" 

& ®\ 



"*  1^  1- 

- L 

~i  ^ 

J?u/ TranMCQmM./Yat^,TL.pJi69. 


r 


'mi  ■/' 


.J 


I 


1 


i 


4 


1 


I 

j 

4 


I 

J 

I 


1 

) 

( 

I 

i 


mi  7ram. 


^ddtiv  ef  tke  l^Trte, 


tZL  one  oicnc£^  speei^tc  ^rgu/itp  107g.  t- 

Jyo  Jjz^iwr  JK/lorsay 

4^"  DAY  5^”  DAY 


J.Basire^  Idh 


Acid  AUcaBne 


F 


S -AliaJme  P Acid 


T7ie  JarialuTTbs  of  lfi&  Addi^  of  idh 


I*"  DAY  21F  DAY  S’?”  DAY 

TojinJloffotajh  ^as  takmy  5 djmkms  of  T<ir^afo  of FclaJhytoJosnj  3 diwdms-  of  larMo  of  fotai, 


J^/UC  TrojisM  WiXm\,Pla/ji  \mp269 


Fri7i£  ivtfk  larfy'ote  of  lotash. 


J. 


! i 


i: 


'i 


; 


j 


,v 

•5 

S 


# 


G T S 9 70  11  JH  ) ^ 


ji 


[ 271  ] 


XV.  Additional  Observations  on  the  Osteology  of  the  Iguanodon  and  Hylceosaurus. 
By  Gideon  Algernon  Mantell,  Esq.,  LL.D.,  F.R.S.,  F.L.S., 
Vice-President  of  the  Geological  Society,  8^c. 


Received  January  15, — Read  March  8,  1849. 

In  the  last  memoir  which  I had  the  honour  of  placing  before  the  Royal  Society, 
allusion  was  made  to  the  discovery  of  some  remains  of  the  Iguanodon  that  tended  to 
elucidate  the  structure  of  certain  parts  of  the  skeleton  of  that  gigantic  terrestrial 
animal,  which  from  the  imperfect  data  previously  obtained,  had  not  been  satisfac- 
torily determined. 

I now  beg  to  submit  to  the  consideration  of  the  Society  the  results  of  a careful 
examination  of  these  fossils,  and  of  other  illustrative  specimens  in  the  collections  of 
my  friends,  in  the  hope  that  this  addition  to  the  previously  recorded  knowledge  of 
the  osteology  of  the  Wealden  Reptiles,  wall  be  found  to  possess  considerable  physio- 
logical interest  and  importance. 

The  fragmentary  and  isolated  condition  of  the  osseous  relics  found  imbedded  in 
the  fluviatile  deposits  of  the  South-East  of  England,  affords  a suflScient  excuse  for 
error  in  the  interpretation  of  a piece  of  bone,  or  in  the  reference  of  an  entire  bone  to 
a particular  genus  or  species.  My  own  mistakes  in  this  respect  I shall  unreservedly 
point  out,  and  I would  fain  hope  that  other  labourers  in  the  same  department  of 
natural  history,  but  of  far  higher  authority,  will  not  hesitate,  after  the  noble  example 
of  the  illustrious  Cuvier,  to  make  similar  admissions ; for  it  is  only  by  substituting 
truth  for  error,  and  facts  for  hypotheses,  that  correct  principles  of  palaeontology  can 
be  established. 

The  fossils  in  my  possession  consist  of  several  bones  of  the  extremities  and  pectoral 
arch,  and  of  cei'vical,  dorsal,  and  caudal  vertebrae  of  the  Iguanodon,  equal  if  not 
surpassing  in  magnitude  any  previously  discovered ; and  portions  of  the  sacrum  of 
individuals  of  different  ages ; together  with  dermal  and  other  bones  of  the  Hylaeo- 
saurus,  Goniopholis,  &c.  The  recent  acquisition  of  some  of  these  relics  excited  in 
my  mind  a desire  to  renew  the  attempt  to  construct  the  skeleton  of  the  colossal  reptile 
whose  remains  were  first  brought  to  light  by  my  early  geological  researches  in  Tilgate 
Forest,  I therefore  repaired  to  the  British  Museum,  and  by  the  kind  permission  of 
Mr.  Konig,  re-examined  many  of  the  fossils  described  in  my  former  works.  I also 
availed  myself  of  the  liberality  of  Capt.  Lambart  Brickenden,  Mr.  Baber,  Mr.  Saull, 
&c.,  to  inspect  their  several  collections,  and  chisel  out  and  figure  or  describe  such 
specimens  as  threw  light  on  the  especial  object  of  my  present  inquiries. 

In  the  difficult  and  tedious  investigations  necessary  to  arrive  at  any  certain  con- 

2 N 2 


272 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


elusions  as  to  the  distinctive  characters  of  the  vertebrae  belonging  to  different  parts 
of  the  spine  of  the  same  species  of  fossil  reptile — in  which  there  is  no  clue  to  guide  us 
through  the  labyrinth  but  analogy — I was  so  fortunate  as  to  obtain  the  invaluable  aid 
of  that  profound  anatomist  and  physiologist,  Dr,  A.  G.  Melville,  without  whose  co- 
operation it  would  have  been  impossible  for  me,  from  the  pressure  of  professional 
engagements,  to  have  instituted  the  requisite  comparison  of  the  specimens  with  the 
corresponding  bones  of  allied  recent  and  fossil  species  ; or  to  have  arrived  at  the 
determination  of  the  true  place  in  the  vertebral  column  of  certain  isolated  vertebrae 
presenting  remarkable  dissimilarities  in  their  characters,  and  which  had  formerly 
been  assigned  by  myself  and  others  to  distinct  genera  of  Saurians. 

As  the  present  communication  may  be  regarded  as  supplementary  to  my  former 
attempts  to  illustrate  the  osteological  structure  of  the  Wealden  reptiles,  I propose, 
for  the  convenience  of  reference,  to  notice  the  various  subjects  under  review,  in  the 
order  adopted  in  my  memoir  published  in  the  Philosophical  Transactions  for  1841. 

Iguanodon.  Angular  Bone  of  the  Lower  Jaw. — With  the  gigantic  femora,  tibiae, 
and  vertebrae,  hereafter  described,  were  found'associated  numerous  fragments  of  large 
ribs,  vertebral  processes,  &c.,  and  a portion  of  a long  arched  bone  of  so  peculiar  a 
shape  as  to  defy  all  my  attempts  to  determine  its  place  in  the  skeleton,  till  the  saga- 
city of  Mr.  Waterhouse  (of  the  British  Museum)  recognized  its  accordance  with  the 
angular  bone  of  a reptile ; an  opinion  which  a careful  comparison  of  the  fossil  with 
recent  types  has  satisfactorily  confirmed.  The  specimen  is  10  inches  in  length,  and 
proves  to  be  the  right  angular  bone  of  the  lower  jaw  of  a large  Iguanodon  ; it  exhibits 
the  deep  longitudinal  channel,  and  the  post-opercular  notch,  peculiar  to  that  maxil- 
lary element  in  Saurians,  but  is  not  sufficiently  perfect  to  afford  an  instructive  deline- 
ation ; the  length  of  the  jaw  to  which  it  belonged  was  probably  from  3 to  4 feet. 

Vertebral  Column. — The  structure  of  the  middle  dorsal  and  anterior  caudal  vertebrae, 
was  first  established  by  the  figures  and  descriptions  given  in  my  various  geological 
works,  and  by  the  references  to  these  parts  of  the  skeleton  in  the  Maidstone  speci- 
men ; for  although  the  vertebrae  in  that  celebrated  fossil  are  more  or  less  distorted 
by  compression,  their  distinctive  characters  are  not  obliterated,  but  may  be  recog- 
nized by  due  attention. 

The  elaborate  and  critical  examination  of  all  the  Saurian  vertebrae  from  the 
Wealden  collected  by  myself  and  others,  given  in  the  masterly  reports  on  the  British 
Fossil  Reptiles  by  Professor  Owen,  undertaken  and  published  at  the  expense  of  the 
British  Association  of  Science  since  the  appearance  of  my  memoir  in  the  Philoso- 
phical Transactions  for  1841,  has  supplied  many  important  diagnostic  details  of 
great  value  to  the  cultivator  of  this  department  of  palaeontology.  But  the  deter- 
mination of  the  cervical,  anterior  dorsal,  lumbar,  and  terminal  caudal,  has  not 
hitherto  been  satisfactorily  accomplished.  For  although  in  my  earlier  attempts  to 
interpret  the  mutilated  and  generally  isolated  relics  of  gigantic  Saurian  skeletons 
which  were  from  time  to  time  exhumed  in  the  Wealds  of  the  south-east  of  England, 
certain  large  vertebrije  of  dissimilar  forms  were  vaguely  assigned  to  the  Iguanodon — 


THE  IGUANODON  AND  HYL^OSAURUS. 


273 


more  from  their  constant  collocation  with  undoubted  bones  of  that  reptile,  and  the 
absence  of  any  remains  of  the  extremities  of  other  species  or  genera  to  which  they 
could  have  belonged,  than  from  any  legitimate  anatomical  deductions — yet  almost 
all  these  bones  have  since  been  referred  to  distinct  genera  by  Professor  Owen*. 

Among  the  fossils  lately  obtained  from  the  Isle  of  Wight,  are  certain  cervical,  an- 
terior and  middle  dorsal,  and  posterior  caudal  vertebrae,  which  so  closely  approxi- 
mate in  their  essential  characters  to  the  other  elements  of  the  spinal  column  of  the 
Iguanodon,  as  to  leave  but  little  doubt  that  they  belong  to  that  animal.  And 
although  in  the  absence  of  any  connected  portions  of  the  anterior  part  of  the  spine 
absolute  certainty  cannot  be  obtained,  the  close  typical  affinity  of  the  bones  in  ques- 
tion supports  this  view  of  the  subject,  rather  than  that  which  assigns  them  to  distinct 
genera  of  reptiles,  of  which  no  other  less  questionable  vestiges  have  been  discovered 
in  the  Wealden  formation. 

I will  now  briefly  state  the  result  of  a careful  examination  and  comparison  of  all 
the  materials  to  which  we  could  obtain  access  ; the  anatomical  details,  and  the  descrip- 
tion of  the  essential  osteological  characters  upon  which  our  opinions  are  based,  have 
been  drawn  up  by  Dr.  Melville,  and  his  subjoined  report  will,  I doubt  not,  be  re- 
garded by  the  scientific  palaeontologist  as  the  most  valuable  part  of  this  memoir. 

Cervical  vertebrae,  Plate  XXVIII,  figs.  4,  6. — In  my  Geology  of  the  South-East  of 
England'l'  (published  in  1833),  several  large  convexo-concave  vertebrae  from  Tilgate 
Forest  are  described  as  presenting  the  true  lacertian  type,  being  concave  anteriorly, 
and  convex  posteriorly,  as  in  the  Iguana,  Monitor,  Crocodile,  &c.,  and  this  statement 
is  repeated  in  my  memoir  of  1841:}:.  But  Professor  Owen,  from  a more  accurate 
examination  of  one  of  these  bones  (now  in  the  British  Museum),  in  which  the  poste- 
rior oblique  processes  remain,  discovered  that  the  relative  position  of  this  vertebra 
in  the  skeleton  must  have  been  the  reverse  of  that  which  I had  assigned  to  it ; the 
convexity  being  anterior  and  the  concavity  posterior.  A similar  deviation  from  the 
ordinary  Saurian  structure  had  long  since  been  detected  by  Cuvier  in  a fossil  croco- 
dilian found  at  Honfleur,  and  figured  and  described  in  the  “ Ossemens  Fossiles"  (tome  v. 
p,  155) ; and  which,  though  referred  by  Geoffroy  to  the  genus  Steneosaurus,  has  since 
been  named  by  Von  Meyer  Streptospondylus  (reversed  spine)  ; a most  objectionable 
name,  since  the  same  character  prevails  in  several  fossil  genera,  as  well  as  in  many  ex- 
isting Mammalia.  The  fossil  vertebrae  from  Tilgate  Forest,  above  mentioned,  are  as- 
signed by  Professor  Owen  to  the  genus  Streptospondylus  of  Von  Meyer,  as  S.  major 

But  notwithstanding  this  decision,  and  the  adoption  of  Professor  Owen’s  interpre- 

* See  Reports  on  British  Fossil  Reptiles,  vol.  for  1841,  pp.  88-94.  f Page  307. 

t Philosophical  Transactions,  p.  141,  PI.  IX.  fig.  4. 

§ British  Association  Reports,  1841,  p.  91.  The  eminent  author  appears  however  to  have  entertained  some 
doubts  whether  the  appropriation  was  correct,  and  the  vertebra  in  question  .might  not  belong  to  his  genus 
“ Cetiosaurus but  he  dismisses  the  suspicion  with  the  remark,  “ that  the  general  constancy  of  the  vertebrse 
of  the  same  Saurian  in  their  antero-posterior  diameter  forbids  the  supposition  of  a vertebra  6 inches  in  length 
in  the  neck,  being  associated  with  one  3 inches  in  length  in  the  back,”  p.  96. 


274 


DR.  MANTEL L ON  THE  OSTEOLOGY  OF 


tation  of  these  vertebrse  in  my  subsequent  geological  works*,  yet  I could  not  divest 
myself  of  the  idea  that  this  inference  might  be  erroneous,  from  the  fact  that  all  the 
convexo-concave  vertebrse  of  the  Wealden  were  cervical ; it  was  indeed  this  circum- 
stance, and  the  extreme  rarity  of  this  type,  which  deterred  the  Rev.  W.  D.  Conybeare 
and  myself,  at  the  very  commencement  of  my  exploration  of  the  Wealden,  from 
assigning  them  to  the  Iguanodon-f-. 

The  inspection  of  a large  anterior  dorsal  vertebra  of  the  convexo-concave  system, 
recently  obtained  by  me  from  the  Isle  of  Wight  (Plate  XXVIII.  fig.  5),  first  suggested 
to  Dr.  Melville  the  idea  that  this  bone,  as  well  as  the  cervicals  above  described, 
belonged  to  the  Iguanodon  ; and  he  has  spared  neither  time  nor  trouble  to  determine 
the  correctness  of  this  solution  of  the  problem.  To  him,  therefore,  alone  is  due  the 
credit  of  having  first  correctly  interpreted  the  characters  of  this  important  part  of 
the  skeleton,  should  future  discoveries  confirm  our  present  view  of  the  subject. 

The  gradual  transition  from  the  anteriorly  convex  cervical  vertebrae  with  their 
deep  posterior  concavity  (see  Plate  XXVIII.  fig.  4®  and  fig.  4*),  to  the  plano-concave 
vertebrse  of  the  posterior  dorsal  and  lumbar  regions,  appears,  at  least  in  the  absence 
of  the  only  certain  evidence — a naturally  connected  spinal  column — to  warrant  the 
conclusion  that  all  these  vertebral  elements  are  referable  to  the  same  gigantic  herbi- 
vorous Saurian:}:.  If  this  opinion  be  correct,  the  adult  Iguanodon  must  have  ap- 
proached in  the  structure  of  its  vertebral  column,  as  well  as  in  its  maxillary  and 
dental  organs  and  hinder  extremities,  to  that  of  the  Rhinoceros  and  other  large 
pachyderms ; for  in  them  the  convexo-concave  type  characterizes  the  cervical  and 
anterior  dorsal  regions  of  the  spine 

Anterior  dorsal  vertebra,  Plate  XXVIII.  fig.  5. — In  this  specimen  from  Sandown  Bay, 
the  convexity  is  relatively  less  than  in  the  cervical,  and  appears  to  indicate  a gradual 
transition  to  the  flat  or  but  slightly  elevated  face  of  the  middle  dorsal,  as  shown  in 
the  fine  vertebra  found  at  Brook  Bay  with  some  enormous  bones  of  the  extremities 
of  an  Iguanodon;  see  Plate  XXIX.  fig.  Si]. 

* Medals  of  Creation,  p.  725.  Wonders  of  Geology,  6th  edit.  p.  414. 

t See  Geology  of  the  South-East  of  England,  p.  307. 

I A reference  to  Cuvier’s  Oss.  Foss.,  tome  v.  p.  156,  will  show  that  even  in  the  typical  form  of  the  genus 
Streptospondylus  the  same  disappearance  of  the  convexo-concave  character  in  the  middle  and  posterior  dorsals, 
takes  place. 

^ If  the  discrepancy  in  the  relative  proportions  and  configuration  of  the  cervical,  dorsal,  and  caudal  vertebrEe 
be  regarded  as  presenting  objections  to  this  view,  let  it  he  remembered  that  in  the  spinal  column  of  our  domestic 
Mammalia  an  equal  dissimilarity  prevails ; for  example  in  the  Ox,  in  which  the  cervical  are  convexo-concave, 
and  the  convexity  gradually  disappears  in  the  posterior  regions  of  the  spine  ; and  the  bodies  of  the  distal  caudal, 
instead  of  being  solid  throughout  as  in  the  anterior  vertebrse,  have  a large  medullary  cavity  in  the  centre,  as  in 
the  fossil  reptile,  called  Poikilopleuron. 

II  In  my  memoir  of  1841,  a fragment  of  a vertebra,  which  Baron  Cuvier  supposed  to  be  part  of  the  atlas  of 
an  Iguanodon,  is  described  as  such  ; and  the  cast  of  the  spinal  canal  in  calcareous  spar  is  regarded  as  that  of  the 
medulla  oblongata  (Philosophical  Transactions,  Plate  IX.  fig.  1).  This  specimen  has  since  been  cleared  of  the 
sandstone  with  which  it  was  partially  invested,  and  proves  to  be  the  neural  arch  of  a crocodilian  cervical  vertebra. 


THE  IGUANODON  AND  HYLiEOSAURUS. 


275 


Sacral  and  caudal  vertebras,  Plate  XXX. — The  most  important  and  novel  announce- 
ment in  relation  to  the  osteology  of  the  Wealden  reptiles  in  Professor  Owen’s  Reports, 
was  the  exposition  of  the  structure  of  the  sacrum  in  the  three  remarkable  extinct  genera 
of  his  order  Dinosauria;  namely,  the  Megalosaurus,  Hylaeosaurus,  and  Iguanodon  ; 
a peculiarity  of  mechanism  which  had  escaped  the  penetration  of  all  previous  ob- 
servers. No  one  appears  to  have  suspected  that  in  these  reptiles  the  pelvic  arch  was 
composed  of  a greater  number  of  anchylosed  vertebrse  than  in  the  living  Saurians ; 
and  that  the  position  of  the  neural  arches  was  transposed  from  its  usual  place  over 
the  middle  of  the  body  of  the  vertebra,  to  the  ossified  intervertebral  spaces  formed 
by  the  anchylosis  of  the  contiguous  vertebrae ; the  foramina  for  the  transmission  of 
the  sacral  nerves  from  the  spinal  chord  being  situated  above  and  behind  the  middle 
of  the  body  (see  Plate  XXX.  figs.  15,  16)*. 

Fragments  of  the  pelvic  arch,  consisting  of  the  body  of  one  sacral  vertebra,  with  a 
portion  of  the  contiguous  bones  anchylosed  to  each  extremity,  are  not  uncommon  in 
the  Wealden  deposits;  and  so  long  since  as  1826,  Sir  R.  Murchison  transmitted  to 
Baron  Cuvier  a specimen  of  this  kind  (from  Loxwood  in  Sussex-f^),  with  several 
lumbar  and  caudal  vertebree.  Upon  these  relics  the  illustrious  founder  of  palaeonto- 
logy only  remarked,  that  the  united  bodies  of  the  vertebrae  “ seem  to  indicate  that 
the  animal  to  which  they  belonged  made  such  feeble  use  of  its  tail  that  the  caudal 
vertebrae  were  occasionally  anchylosed  together.”  Neither  did  the  magnificent  spe- 
cimen of  the  sacrum  of  the  Megalosaurus,  consisting  of  a series  of  five  united  ver- 
tebrae, made  known  by  the  present  Dean  of  Westminster  in  1824,  suggest  the  correct 
interpretation  of  this  part  of  the  skeleton  of  the  Dinosaurians.  The  announcement 
of  Professor  Owen  was  therefore  to  me  of  especial  interest,  since  it  elucidated  the  na- 
ture of  many  fossils  in  my  collection  which  had  previously  been  undeterminable. 

The  present  investigation  rendering  it  necessary  to  acquire  an  accurate  idea  of  the 
characters  of  the  vertebrae  composing  the  pelvic  arch  of  the  Iguanodon,  I obtained 
permission  of  Mr.  Saull  to  have  the  fine  specimen  of  a sacrum  in  his  museum  (de- 
scribed in  Report  of  Brit.  Assoc,  p.  131),  more  completely  developed  at  my  own  ex- 
pense, as  its  true  characters  were  in  some  measure  obscured  by  the  coating  of  hard 
calcareous  grit  with  which,  as  is  generally  the  case  with  the  Isle  of  Wight  Wealden 
fossils,  it  was  partially  invested.  This  interesting  and  instructive  relic  is  figured  as 
it  now  appears  in  Plate  XXVI. ; half  the  natural  size  in  linear  dimension. 

This  sacrum  consists  of  six  anchylosed  vertebrse  (not  oijive  as  described  in  the 
Reports  on  Brit.  Foss.  Reptiles,  p.  130),  with  the  right  iliac  bone  attached.  The  re- 
lative size  and  proportions  of  the  several  bones  composing  the  sacral  arch  are  now 
well  displayed.  The  body  of  the  first  or  anterior  vertebra  (Plate  XXVI.  1)  is  large, 
strong,  and  expanded,  forming  a powerful  buttress  in  front ; the  bodies  of  the  two 
posterior  vertebrse  (Plate  XXVI.  5, 6)  are  likewise  large  and  strong ; but  the  second, 
third,  and  fourth,  are  constricted  laterally  in  the  middle  (Plate  XXVI.  2,  3,  4),  and 

* See  Reports  on  Brit.  Foss.  Reptiles,  1842,  p.  105. 

t Geological  Transactions,  vol.  ii.  (New  Series),  p,  105,  Plate  XY.  figs.  4,  6. 


276 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


are  more  slender  than  either  the  anterior  or  posterior ; by  this  modification  of  the 
elements  of  the  sacral  arch,  both  lightness  and  strength  were  obtained. 

A similar  construction  is  present  in  every  specimen  of  the  sacrum  that  has  come 
under  my  observation,  whether  of  young  and  small,  or  of  old  and  large  individuals ; 
in  all,  the  same  relative  proportions  in  the  size  of  the  vertebrae  are  present,  as  in 
Mr.  Saull’s  fossil. 

A portion  of  the  sacrum  of  a young  Dinosaurian  consisting  of  four  vertebrae, — the 
two  posterior  and  two  of  the  middle  series — recently  discovered  in  Tilgate  Forestand 
presented  to  me  by  Captain  Lambart  Brickenden,  is  represented  of  the  natural 
size  in  Plate  XXVII.  This  fossil  beautifully  exhibits  the  forms  of  the  bodies  of  the 
vertebrae,  and  the  attachment  of  the  neural  arches  to  the  anchylosed  intervertebral 
spaces.  The  vertebrae  differ  so  much  in  iheir  proportions  and  configuration  from 
those  in  the  fossil  figured  in  Plate  XXVI.,  as  to  render  it  doubtful  whether  this 
specimen  may  not  be  a portion  of  the  sacral  arch  of  the  Hylaeosaurus : this  subject 
will  be  more  fully  considered  by  Dr.  Melville  in  the  subjoined  report*. 

Another  highly  interesting  series  of  the  sacral  vertebrae,  with  four  consecutive  an- 
terior caudals  of  the  same  reptile,  found  by  Peter  Martin,  Esq.,  at  Charlwood  in 
Surrey,  are  figured  in  Plate  XXX.  figs.  15,  16,  17,  one-fourth  the  natural  size.  The 
portions  of  the  sacrum  consist  of  the  anterior,  three  middle,  and  one  of  the  posterior 
vertebrae,  all  of  which  are  more  or  less  mutilated  (Plate  XXX.  figs.  15,  16).  The  im- 
plantation of  the  neural  arches  in  the  intervertebral  spaces,  the  coalescence  of  the 
expansion  above,  and  the  foramina  for  the  transit  of  the  sacral  nerves  (fig.  ] 5,  z),  are 
well  shown : and  the  relative  size  of  the  last  sacral  and  first  caudals  is  seen  in  the 
series  of  four  anterior  caudal  vertebrae  (fig.  17).  The  absence  of  a chevron  bone  at 
the  junction  of  the  two  first  caudals  (fig.  \7,x),  and  the  presence  of  this  element  in 
the  succeeding  interspaces  (fig.  17,  b *,  *),  seem  to  indicate  that  the  first  of  this  series  is 
the  second  caudal;  as  the  deep  concavity  of  the  posterior  anchylosed  sacral  vertebra 
renders  it  probable  that  the  anterior  face  of  the  first  caudal — the  bone  which  unites 
the  tail  to  the  pelvis — was  more  or  less  convex ; as  is  the  case  in  the  Crocodile, 
Gavial,  Scc.-f- 

Pelvis. — Of  the  pelvic  bones,  the  Iliac,  of  which  both  the  right  and  left  are  pre- 
served in  the  Maidstone  specimen,  and  the  right  Ilium  in  the  sacrum  figured  in 
Plate  XXVI.,  are  alone  determined.  There  are  portions  of  large  bones  in  my  former 

* Among  the  water- worn  masses  of  bone  so  abundantly  strewn  along  those  parts  of  the  southern  shores  of 
the  Isle  of  Wight,  which  are  bounded  by  clilFs  of  the  Wealden  strata,  I had  often  met  with  specimens  in 
which  the  body  of  a very  large  vertebra  is  anchylosed  to  one  so  disproportionately  small,  that  I could  not  ex- 
plain their  origin,  until  Professor  Owen’s  description  of  the  structure  of  the  sacrum  suggested  their  true  nature. 
These  fossils  are  in  fact  one  of  the  large  vertebrae  either  of  the  anterior  or  posterior  end  of  the  sacrum  united  to 
one  of  the  slender  middle  vertebrae.  A specimen  of  this  kind  in  the  highly  interesting  collection  of  Mr.  Baber, 
is  of  enormous  size  ; the  anterior  face  of  the  largest  vertebra  being  inches  by  6^  in  diameter.  This  fossil  is 
also  interesting  on  another  account,  for  on  one  side  of  the  body  of  the  largest  vertebra  there  is  an  abnormal 
enlargement  (or  exostosis) : I have  observed  similar  bony  tumours  on  the  sides  of  the  bodies  of  other  vertebrae. 

t See  Wonders  of  Geology,  sixth  edition,  p.  419. 


THE  IGUANODON  AND  H YLA20SAURUS. 


277 


collection  which  unquestionably  belong  to  the  pelvic  region  of  some  great  Saurian, 
most  probably  of  the  Iguanodon,  but  at  present  all  the  elements  of  this  part  of  the 
skeleton  have  not  been  found  in  a state  suffieiently  recognizable  to  admit  of  their 
positive  identification. 

Caudal  vertebrce. — The  characters  of  the  anterior  caudals  are  so  well  known  that  it 
is  unnecessary  to  describe  them  ; but  on  the  somewhat  angular  caudals,  originally 
referred  by  me  to  the  Iguanodon,  and  subsequently  ascribed  to  the  Cetiosaurus  by 
Professor  Owen,  and  now  restored  to  the  former  reptile  by  Dr.  Melville,  I will  offer  a 
few  remarks.  In  the  first  place,  in  confirmation  of  the  opinion  that  these  vertebrae 
belong  to  the  Iguanodon,  I would  especially  call  attention  to  the  fact,  that  with  the 
unquestionable  Iguanodon  sacrals  found  at  Loxwood,  and  examined  by  Baron  Cuvier 
(as  previously  mentioned,  ante,  p.  275),  were  several  caudals  belonging  to  the  same 
individual,  and  these  possess  the  angular  form,  and  more  or  less  grooved  base,  as  may 
be  seen  by  reference  to  the  Geological  Transactions,  vol.  ii.  New  Series,  pi.  1.5.  figs. 
1,3.  I can  vouch  for  the  accuracy  of  the  figures  from  having  carefully  examined 
the  specimens  at  the  time  they  were  being  drawn  by  that  able  artist,  Mr.  Scharf. 

I would  next  call  attention  to  the  spine  of  the  Hylaeosaurus,  which  exhibits  in  the 
several  modifications  of  its  vertebrae,  as  great  a discrepancy  in  the  elements  of  the 
dorsal  and  caudal  regions,  as  our  proposed  restoration  of  the  spinal  column  of  the 
Iguanodon.  In  the  highly  instructive  specimen  from  the  Weald  of  Sussex,  represented 
on  a small  scale  (one-sixth  linear)  in  Plate  XXXII.  fig.  22,  a nearly  uninterrupted 
chain  of  vertebrae  is  preserved,  commencing  with  the  first  caudals.  The  marked 
angular  character  of  the  middle  and  distal  vertebrae  is  most  obvious  ; and  the  differ- 
ence between  these  bones  and  the  anterior  caudals,  and  the  corresponding  modifi- 
cations in  the  form  of  the  chevron  bones,  are  as  great  as  those  presented  by  the 
vertebrae  we  have  ascribed  to  the  different  regions  of  the  spine  in  the  Iguanodon. 

If  this  chain  of  vertebrae  of  the  Hylaeosaurus  had  not  been  found  in  connection  with 
unquestionable  bones  of  that  reptile,  namely,  the  dermal  scutes  and  spines,  no  one 
could  have  established  their  relation  ; and  the  tail  of  this  Wealden  reptile  would  have 
run  the  risk  of  being  for  ever  separated  from  the  body  to  which  it  originally  belonged, 
and  would  probably  have  been  honoured  with  a distinct  generic  appellation. 

The  chevron  bones  in  the  Hylaeosaurus  present  a remarkable  variation  in  form,  as 
is  shown  in  Plate  XXXII.  fig.  22.  The  most  anterior  (fig.  22 g)  has  a double  head 
for  articulation  with  the  body  of  the  vertebra  ; in  the  next  variety  (fig.  22 f)  the  two 
articulating  facets  are  confluent  as  in  the  Iguanodon  ; in  the  distal  (fig.  22  e)  the 
chevron  bones  are  so  much  elongated  in  a horizontal  direction  in  a line  with  the  axis 
of  the  body,  as  to  be  in  contact  with  each  other  in  the  centre ; this  part  of  the  tail 
must  therefore  have  formed  a very  strong  elastic  subcylindrical  chain  or  chord. 

Pectoral  arch. — I now  arrive  at  the  consideration  of  that  part  of  the  skeleton  re- 
specting which,  happily,  no  controversy  can  arise,  and  that  has  been  established  bv 
my  own  discoveries  and  investigations.  By  a reference  to  my  former  paper*,  it 

* Philosophical  Transactions,  1841,  Plate  VIII.  fig.  19. 

2 o 


MDCCCXLIX. 


278 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


be  seen  that  the  clavicles  of  the  Iguanodon  were  recognized  from  two  of  these 
bones  occurring  in  the  Maidstone  specimen ; and  that  a coracoid  bone,  10  inches 
wide,  was  also  ascribed  to  the  same  reptile*,  from  several  examples  having 
been  found  with  undoubted  bones  of  the  Iguanodon  : but  the  latter  reference  was 
only  provisional,  since  there  was  no  connecting  link  to  unite  this  element  to  the 
other  parts  of  the  pectoral  arch.  A scapula,  18  inches  long-j-,  for  a similar  reason 
was  placed  in  the  same  category ; but  with  the  precautionary  remark,  “ that  neither 
of  the  specimens  was  found  in  natural  apposition  or  connexion  with  other  portions 
of  the  skeleton,  but  only  imbedded  in  the  same  mass  of  rock.”  I have  often  vainly 
attempted  to  find  such  a correspondence  between  the  articulating  facets  of  the  cora- 
coid and  scapula  above  mentioned,  as  would  warrant  the  conclusion  that  they  origi- 
nally belonged  to  the  same  genus  of  Saurians.  By  the  fortunate  discovery  of  a perfect 
scapula  (Plate  XXX.  fig.  10)  which  fulfils  these  conditions,  and  can  also  be  proved  to 
belong  to  the  Iguanodon,  both  the  bones  forming  the  shoulder-joint  are  now  for  the 
first  time  determined. 

This  specimen  is  delineated  one-fourth  the  natural  size  in  Plate  XXX.  fig.  10  ; when 
obtained  it  was  firmly  imbedded  in  the  hard  Tilgate  sandstone,  and  broken  into 
several  pieces:  I succeeded  in  extricating  the  whole  from  the  rock,  and  in  reuniting 
the  dissevered  parts,  so  as  to  demonstrate  the  perfect  form  of  this  most  interesting 
fossil.  It  is  the  right  scapula,  and  is  13  inches  long,  5^  inches  wide  at  the  humeral 
and  4 at  the  upper  or  spinal  extremity;  like  that  of  the  Crocodile  it  is  slender, 
flat,  and  slightly  arched  ; at  the  humeral  end  it  becomes  thick  and  expanded  to  form 
the  apophysial  surface  that  united  with  the  coracoid,  and  the  outer  half  of  the  glenoid 
cavity  to  receive  the  head  of  the  humerus ; it  is  flat  and  very  thin  at  the  upper  or 
spinal  end.  This  bone  differs  essentially  from  the  scapula  of  the  Iguanas,  Monitors, 
&c,,  and  approximates  to  that  of  the  Crocodiles  and  Scinks ; the  minute  scapula  of 
the  Chameleons  presents  the  same  simple  character. 

Upon  placing  this  scapula  in  juxtaposition  with  a coracoid  of  the  form  assigned  to 
the  Iguanodon it  will  be  manifest  that  the  two  bones  must  have  belonged  to  the 
same  scapular  arch  ; as  is  shown  in  Plate  XXX.  figs.  10  and  11.  The  close  resem- 
blance between  this  form  of  pectoral  arch  and  that  of  the  Hyleeosaurus  will  be  seen 
at  a glance  by  reference  to  the  figures  of  the  latter  §.  The  scapula  of  the  Iguanodon 
differs  from  that  of  the  Hylaeosaurus  in  having  the  body  more  arched  and  slender, 
and  the  neck  more  contracted  ; and  in  the  absence  of  the  strong  acromial  ridge  which 
characterizes  the  latter.  The  coracoid  (Plate  XXX.  fig.  1 1)  differs  chiefly  in  its  greater 
external  convexity  and  inner  concavity,  and  in  the  apophysial  scapular  surface 
being  separated  from  the  glenoid  facet  by  a deep  notch  (Plate  XXX.  fig.  lie)  for  the 
passage  of  vessels,  instead  of  having  a simple  perforation  as  in  the  Hylaeosaurus.  In 
both  these  reptiles,  however,  there  is  a closer  affinity  in  the  structure  of  the  pectoral 
arch,  than  I have  observed  between  other  extinct  forms. 

* Philosophical  Transactions,  1841,  Plate  IX.  fig.  11.  p.  138. 

X Ibid.  Plate  IX.  fig.  11. 


t Ibid.  Plate  IX.  fig.  10. 
§ Ibid.  Plate  X.  fig.  8. 


THE  IGUANODON  AND  HYL^OSAURUS. 


279 


While  examining^  the  scapula  above  described,  I was  re-  Fig-  i- 

minded  of  the  fractured  portions  of  two  long-  flat  bones  Part  of  the  Maidstone  Iguanodon. 

in  the  Maidstone  specimen  which  I had  often  in  vain 
attempted  to  decipher.  One  of  these  bones*  lies  across 
the  rig-ht  femur,  as  shown  in  the  annexed  diag’ram  (fig;.  1). 

Upon  repairing’  to  the  British  Museum,  the  identity  of  these 
bones  was  immediately  apparent ; they  prove  to  be  the 
right  and  left  scapulae ; consequently  the  coracoids  above 
mentioned,  which  are  adapted  to  this  form  of  scapula,  also 
belong-  to  the  Iguanodon-j-. 

As  the  clavicles,  coracoids,  and  scapulce,  are  now  deter- 
mined, the  structure  of  the  pectoral  arch  of  the  Iguanodon 
may  be  regarded  as  established ; and  although  the  sternum 
is  at  present  unknown,  and  the  relative  position  of  the  several 
parts  can  only  be  conjectured,  I have  ventured  to  attempt 
the  restoration  of  this  important  part  of  the  skeleton  of 
the  extraordinary  being  on  whose  osteology  I have  bestowed  so  much  time  and 
labour.  The  annexed  outline  represents  the  arrangement  which  appears  to  me  the 
most  natural. 

Fig.  2. 

Restoration  of  the  Pectoral  Arch  of  the  Iguanodon. 


1.  Two  metacarpal  bones. 

2.  Four  consecutive  dorsal  vertebrae. 

3.  A detached  dorsal  vertebra. 

4.  Humerus. 

5.  A detached  rib. 

6.  The  right  femur. 

7.  Scapula  lying  across  the  shaft  of  the  femur. 

8.  Distal  end  of  the  corresponding  Scapula. 

9.  A detached  dorsal  vertebra. 


* Figured  in  Philosophical  Transactions,  1841,  Plate  VIII.  fig.  30. 

t The  Scapula  with  a long  slender  process  extending  from  the  head  of  the  bone,  which  is  figured  in  Philo- 

2 o 2 


280 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


Bones  of  the  Extremities. 

Humerus  of  the  Iguanodon,  Plate  XXXI. — It  may  be  worth  remarking',  that  although 
numerous  femora,  tibiae,  and  other  bones  of  the  hinder  extremities  were  discovered 
in  various  localities,  no  certain  remains  of  the  fore-legs  had  occurred  except  the 
slender  bones  described  by  me  as  metacarpals*.  Professor  OwEN'f'  suggested  that 
some  of  the  bones  in  the  British  Museum,  which  I had  considered  as  femora,  might 
possibly  be  humeri,  and  the  observations  of  a correspondent  are  quoted  by  him  in 
corroboration  of  this  opinion ; but  I feel  confident  that  no  one  who  will  give  suf- 
ficient attention  to  the  subject,  can  for  a moment  admit  the  validity  of  the  reasons 
adduced.  The  question  however  is  now  decided  by  the  discovery  of  a bone  found 
in  the  Wealden  of  the  Isle  of  Wight,  associated  with  other  remains  of  the  Iguanodon ; 
and  which  is  undoubtedly  a humerus,  because  it  cannot  possibly  be  referred  to  any 
other  part  of  the  skeleton,  and  possesses  all  the  essential  characters  of  the  principal 
bone  of  the  anterior  extremity  of  a gigantic  reptile.  Most  fortunately,  too,  it  can  be 
proved  to  belong  to  the  Iguanodon  ; for  it  is  identical  with  a well-preserved,  but 
much  smaller  bone,  in  the  Maidstone  specimen  (Plate  XXXI.  fig.  20). 

In  my  memoir  of  1841,  this  last  bone  is  figured:]:,  with  the  remark  that  “it  pro- 
bably belongs  to  the  brachial  extremity ; it  is  imbedded  near  the  two  metacarpals, 
but  I have  not  been  able  to  determine  its  character  satisfactorily.”  The  relatively 
very  small  size  of  this  bone  appeared  to  be  an  insuperable  objection  to  the  regarding 
it  as  the  humerus,  and  it  therefore  seemed  to  me  more  probable  that  it  was  one  of  the 
bones  of  the  fore-arm,  possibly  the  radius.  In  the  Reports  on  British  Fossil  Reptiles 
it  is  stated  that  this  bone  corresponds  with  certain  bones  of  the  foot  found  at 
Horsham  ; but  both  the  extremities  of  the  fossil  in  question  entirely  differ  from  the 
articulating  surfaces  of  all  the  metacarpals  and  metatarsals  of  the  Iguanodon  that 
have  come  under  my  observation.  The  comparison  of  this  specimen  with  the  humerus 
from  the  Isle  of  Wight  will  at  once  establish  its  true  relations. 

The  humerus  from  the  Isle  of  Wight  was  discovered  by  Mr.  Fowlstone,  to  whom 
I am  indebted  for  the  loan  of  it;  it  is  figured  ^th  the  natural  size,  in  Plate  XXXI. 
fig.  19;  fig.  19“  representing  the  posterior,  and  fig.  19*  the  anterior  aspect.  This 
fine  bone  is  entire,  with  the  exception  of  the  outer  tuberosity  of  the  head  ; its  dimen- 
sions are  as  follow  : — 

Greatest  length  . 3 feet. 

Length  in  a straight  line  from  the  inner  tubercle  of  the  head  to]  i • i 
the  inner  condyle J 


sophical  Transactions,  1841,  Plate  IX.  fig.  10,  must  therefore  be  referred  to  some  other  genus  of  the  Wealden 
reptiles ; it  may  possibly  belong  to  the  Megalosaurus,  in  which  the  coracoid  (Geol.  Trans.,  vol.  vi.  pi.  43,  fig.  3) 
is  of  a more  complicated  structure  than  in  the  Iguanodon  and  Hylaeosaurus,  and  somewhat  resembles  that  of 
the  Iguanas  or  Varanians. 

* Philosophical  Transactions,  1841,  Plate  VIII.  fig.  14. 

t Reports  on  British  Fossil  Reptiles,  1841,  p.  138. 

X Philosophical  Transactions,  Plate  VIII.  fig.  5.  § Page  140. 


THE  IGUANODON  AND  H YL^EOSAURUS. 


281 


From  the  outer  tubercle  of  the  head  to  the  external  condyle  . . 33  inches. 

Circumference  of  the  head 23^ 

round  the  condyles 21^ 

Circumference  of  the  shaft  at  the  deltoid  crest 

one-third  from  the  distal  extremity  16 

The  medullary  cavity  only  extends  to  within  one-third  of  the  top  of  the  bone ; it  is 
3 inches  in  diameter:  the  greatest  thickness  of  the  wall  of  the  shaft  is  1 inch. 

The  head  of  the  bone  presents  the  usual  posterior  protuberance  of  the  humerus  in 
Lizards,  but  the  epiphysis  of  this,  as  well  as  of  the  distal  extremity,  is  wanting,  as  is  the 
case  in  all  the  long  bones  of  the  Wealden  reptiles.  At  about  3 inches  from  the  top  the 
ridge  or  crest  for  the  insertion  of  the  deltoid  muscle  (d)  is  considerably  developed,  and 
extends  15  inches  down  the  shaft,  which  rapidly  contracts  below,  and  finally  expands 
to  form  the  condyloid  extremity.  The  articular  face  of  the  latter  (Plate  XXXI.  fig.  1 9"^) 
is  divided  into  two  nearly  equal  condyles  ; the  inner  or  ulnar  segment  (e)  is  traversed 
by  an  anterior  furrow,  which  is  more  strongly  marked  in  the  humerus  of  a younger 
individual  (Plate  XXXI.  fig.  18“^  e) : the  posterior  or  olecranal  fossa  (g)  is  simple,  and 
somewhat  deeper  than  the  anterior.  On  the  whole,  the  aspect  of  this  humerus  more 
closely  corresponds  with  that  of  the  Crocodiles  than  of  the  ordinary  Lizards. 

I have  for  many  years  possessed  the  head  or  proximal  extremity  and  the  lower  or 
condyloid  end  of  two  humeri,  which  must  have  belonged  to  very  young  Iguanodons. 
The  former  is  of  a left  humerus;  it  is  8 inches  in  circumference,  and  with  the  excep- 
tion of  the  absence  of  the  epiphysis,  is  remarkably  perfect ; it  is  identical  with  the 
large  specimen,  and  is  figured  one-third  its  natural  size,  Plate  XXXI.  fig.  21.  The 
specimen  of  the  lower  or  distal  end  of  a right  humerus  is  represented,  Plate  XXXI. 
fig.  18;  it  beautifully  displays  the  condyloid  facet  for  articulation  with  the  bones  of 
the  fore-arm.  In  all  these  fossils  the  medullary  cavity  is  large,  and  extends  to  within 
about  one-third  of  the  top. 

In  the  same  plate  (Plate  XXXI.  fig.  20)  is  given  a figure  of  the  humerus  in  the  Maid- 
stone specimen,  one-sixth  its  natural  size;  the  situation  of  this  bone  is  pointed  out 
in  the  outline*  of  the  scapula  and  adjacent  bones.  Thus  after  the  lapse  of  fifteen 
years  two  important  elements  of  the  skeleton  of  the  Iguanodon  contained  in  that 
most  valuable  fossil,  are  now  for  the  first  time  determined.  The  small  size  of  the 
humeri,  as  compared  with  that  of  the  femora,  seems  at  first  to  present  an  objection 
to  this  interpretation ; but  the  difference  is  not  greater  than  obtains  in  many  other 
fossil  Saurians'l',  as  well  as  in  recent  Lizards.  The  length  of  the  Maidstone  humerus 

* Ante,  p.  279,  fig.  1. 

t “ C’est  un  fait  a peu  pres  general  que  les  membres  ant^rieurs  des  reptiles  crocodiliens  et  lacertiens  sont 
plus  courts  et  plus  faibles  que  les  posterieurs ; chez  quelques  especes  la  difference  est  tres-prononcee.  Mais 
nos  reptiles  fossiles  des  environs  de  Caen  annoncent  une  disproportion  beaucoup  plus  forte  encore  entre  ces 
membres : le  Pcekilopleuron,  le  Steneosaurus  de  Quilly,  les  Teleosaurus,  en  fournissent  la  preuve.  Ces  der- 
niers  surtout  avaient  les  membres  anterieurs  d’une  excessive  petitesse ; les  deux  paires  de  membres  dilferaient 
entre  elles  plus  peut-etre  qu’elles  ne  different  les  Gerbilles  et  les  Kangaroos.” — Deslongchamps,  Memoire  sur 
le  Pakilopleuron  Bucklandii,  p.  81. 


282 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


is  about  20  inches,  that  of  the  contiguous  femur  33  inches;  but  as  the  latter  is 
somewhat  flattened  and  extended  by  compression,  the  difference  is  probably  not  more 
than  one-third.  The  Isle  of  Wight  humerus  is  3 feet  long ; the  largest  femur  I 
have  seen  is  4 feet  8 inches ; the  average  size  of  the  femur  in  the  adult  was  probably 
about  4 feet ; this  bone  therefore  presents  the  same  proportionate  length  as  the 
Maidstone  humerus. 

Hinder  extremities. — The  femur,  tibia,  fibula,  metatarsals,  phalangeals,and  ungueals, 
have  long  since  been  discovered  and  determined* * * §;  but  the  bones  of  the  tarsus  as 
well  as  of  the  carpus  are  still  unknown.  I should  have  passed  over  these  parts  of  the 
skeleton  without  remark,  but  that  some  of  the  femora,  tibiae,  &c.  which  I have 
recently  obtained  are  of  such  enormous  proportions,  as  to  require  notice  in  proof  of 
the  colossal  size  which  some  individuals  must  have  attained. 

In  the  course  of  last  autumn  I procured  from  the  cliffs  near  Brook  Point, — a locality 
well  known  to  the  British  geologist  from  the  fossil  forest  exposed  at  its  base-f, — por- 
tions of  two  corresponding  femora,  tibiae,  and  several  vertebrae,  fragments  of  ribs,  &c. 
of  Iguanodons.  The  most  entire  bone  is  the  left  femur;  it  consists  of  the  shaft  from 
above  the  popliteal  space  to  the  root  of  the  outer  trochanter  : the  head  and  condyles 
are  both  wanting;  the  inner  trochanter  remains;  the  length  of  this  fossil  is  3 feet; 
circumference  of  the  shaft  27  inches.  The  greatest  thickness  of  the  wall  of  the  shaft 
is  2 inches;  the  diameter  of  the  medullary  cavity  5 inches  by  3 ; in. all  the  femora 
which  I have  examined  the  medullary  canal  extends  from  above  the  condyles  to 
within  one-third  of  the  top  of  the  bone§.  Of  the  right  femur,  which  from  its  corre- 
spondence in  size  is  probably  referable  to  the  same  individual  as  the  left,  two  large 
portions  of  the  shaft  were  alone  obtained.  Now  if  we  take  as  a scale  of  proportions 
one  of  the  large  femora  in  the  British  Museum,  the  bone  above  described,  if  perfect. 


would  give  the  following  admeasurements  : — 

Total  length 4 feet  8 inches. 

Circumference  of  the  head  exclusive  of  the  outer  trochanter  . . . 3 — 2 

the  shaft  at  the  base  of  the  middle  trochanter  . 2 — 1 

the  distal  end  round  the  condyles 3 — 6 


One  of  the  tibiee  found  with  the  above,  consists  of  about  two-thirds  of  the  shaft, 
with  the  distal  or  tarsal  extremity  nearly  entire : the  following  are  its  dimen- 
sions : — 

* Philosophical  Transactions,  1841,  Plate  VIII. 

t See  my  “ Geological  Excursions  round  the  Isle  of  Wight,”  p.  277. 

I Philosophical  Transactions,  1841,  Plate  VIII.  fig.  1,  for  an  outline  of  the  perfect  form  of  the  femur  of  the 
Iguanodon. 

§ In  this  enormous  bone  the  internal  structure  is  beautifully  preserved ; sections  properly  prepared  exhibit 
the  peculiar  form  and  proportions  which  Mr.  Bowehbank  considers  to  be  characteristic  of  the  reptilian  type. 
That  eminent  microscopic  observer  has  kindly  favoured  me  with  his  measurements  of  the  bone-cells  in  portions 
of  this  femur.  The  general  average  of  the  proportions  of  the  length  and  diameter  of  the  cells  is  as  one  to  eleven 
and  a quarter ; the  length  being  and  the  diameter  sV^th  of  an  inch. 


THE  IGUANODON  AND  H YL^EOSAURUS. 


283 


Length  along  the  middle  of  the  shaft 27  inches. 

Length  to  the  distal  inner  process 32 

Circumference  of  the  distal  or  tarsal  end  ....  25 

middle  of  the  shaft  . . . . 18 

upper  part 20^ 

Probable  length  of  this  tibia  when  entire,  4 feet. 


A fragment  of  the  shaft  of  a tibia  found  with  the  above,  is  23  inches  in  circum- 
ference. The  distal  end  of  another  tibia,  from  Sandown  Bay,  is  27  inches  in  circum- 
ference. As  a contrast  to  these  gigantic  remains,  I may  state,  that  bones  of  the  ex- 
tremity occasionally  occur  so  small,  yet  so  compact,  as  to  suggest  the  probability 
that  they  may  belong  to  distinct  species ; but  at  present  I have  not  been  able  to  de- 
tect other  characters  which  would  warrant  such  an  inference.  A left  femur  in  my 
possession,  from  Rusper  in  Sussex,  is  14^  inches  long;  circumference  of  the  shaft 
6 inches  ; this  therefore  is  but  one-fourth  the  size  of  the  specimen  from  Brook.  The 
lower  portion  of  a thigh-bone,  which  in  the  characters  of  its  condyloid  extremity 
entirely  agrees  with  all  the  recognized  femora  of  the  Iguanodon,  is  but  3^  inches  in 
circumference  round  the  condyles,  and  but  2^  round  the  shaft  immediately  above  them  ; 
the  total  length  of  this  femur,  when  entire,  could  not  have  exceeded  4^  inches. 

In  general  the  circumference  of  the  shaft  of  the  thigh-bone  immediately  below  the 
base  of  the  inner  trochanter,  is  nearly  equal  to  half  the  length  of  the  entire  bone  ; for 
example,  the  large  right  femur  from  Sussex  in  the  British  Museum,  which  is  3 feet 
8 inches  long,  is  21  inches  round  the  shaft.  But  there  are  exceptions  to  these  pro- 
poi’tions ; thus  the  femur  from  Brook  Point,  presented  by  me  to  the  Hunterian  Mu- 
seum of  the  Royal  College  of  Surgeons,  is  relatively  shorter,  for  it  is  only  3^  feet 
long,  while  the  circumference  of  the  shaft  is  24  inches.  The  thigh-bone  of  the  Maid- 
stone fossil  is  of  more  slender  proportions.  The  tibia  is  about  one-tenth  shorter  than 
the  corresponding  femur  ; and  the  fibula  somewhat  shorter  than  the  tibia.  With  the 
view  of  affording  a general  idea  of  the  dimensions  of  the  known  parts  of  the  skeleton 
of  the  Iguanodon,  to  whieh  the  largest  femur  in  my  possession  belonged,  the  following 
list,  calculated  from  the  average  size  of  numerous  specimens,  is  subjoined  ; the  length 
of  the  corresponding  bones  in  the  Maidstone  fossil  is  added  for  comparison. 

Iguanodon  from  the  Isle  of  Wight.  Maidstone  Iguanodon. 


Femur,  length  of 4 feet  8 inches.  2 feet  9 inches. 

Tibia 4—1  ....2—6 

Fibula 3 — 8 .... 

Humerus 3 — 2 ....1  — 8 

Clavicle 4 — ....2  — 4 

Scapula 3 — 4 . ...  2 — 1 

Metacarpals 2 — 2 ....1  — 2 

Ilium 3 — 10  . ...  2 — 4 

Metatarsals 1 — 11  ....1  — 2 

Ungueal  bones 5f  . . . . 3| 


284 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


Dermal  boties,  Plate  XXXII. — Several  dermal  bones  have  been  discovered  since  my 
last  communication  on  this  subject,  some  of  which  are  clearly  referable  to  the  Hylseo- 
saiirus,  while  others  may  with  great  probability  be  assigned  to  the  Iguanodon,  from 
their  obvious  difference  from  those  found  associated  with  the  bones  of  the  former 
reptile.  Some  dermal  spines  or  tubercles  resembling  that  which  I figured  and  de- 
scribed as  the  horn  of  the  Iguanodon  in  my  “Fossils  of  Tilgate  Forest,”  have  been 
found  at  Hastings,  and  in  the  Isle  of  Wight.  One  remarkably  fine  example  of  a 
conical  dermal  tubercle  or  horn,  in  which  the  core  or  base  is  ossified,  was  obtained 
from  the  Wealden  at  Ridgway  near  Weymouth,  by  Mr.  Shipp  of  Blandford,  and  several 
bones  of  the  Iguanodon  were  found  in  the  same  locality  ; it  is  figured  in  Plate  XXXII. 
fig.  24.  Several  somewhat  angular  bones,  of  coarse  texture,  5 or  6 inches  long, 
which  resemble  in  form  the  spinous  warts  seen  in  the  Amblyrhynchus  and  other 
Iguanidse,  have  likewise  been  obtained  from  Sandown  Bay.  In  the  absence  of  proofs 
derived  from  direct  connection  or  contiguity  with  known  parts  of  the  skeleton,  it  is 
useless  to  attempt  appropriating  these  dermal  appendages  to  particular  Saurians. 
But  in  the  case  of  the  Hylaeosaurus  the  dermal  bones  peculiar  to  that  animal  are 
easily  recognizable ; for  not  only  have  I found  them  in  the  typical  specimen  of  this 
reptile  discovered  in  1832*,  but  likewise  in  the  beautiful  series  of  vertebrae  already 
referred  to'f-,  Plate  XXXII.  fig.  22  ; in  which  the  discoidal  and  oval  scutes  are 
situated  on  each  side  the  spinous  processes  of  the  vertebrae. 

The  same  fossil  contains,  at  the  anterior  part,  portions  of  large  angular  spines  re- 
sembling those  described  in  my  former  memoir;};.  As  the  correctness  of  my  opinion 
that  the  large  flat  spines  in  the  first-discovered  specimen  of  the  Hylaeosaurus  were 
dermal,  and  extended  down  the  back  as  a dorsal  fringe,  has  been  questioned  by 
Professor  Owen  I beg  to  state,  that  since  my  former  communication  I have  submitted 
sections  of  one  of  these  spines  to  microscopical  examination,  and  if  identity  of 
internal  structure  be  of  any  value,  my  interpretation  is  substantiated  ; for  the  same 
remarkable  organization  is  present  as  in  the  admitted  dermal  scutes,  namely, 
“ straight  spicular  fibres  decussating  each  other  in  all  directions,  and  seeming  to  re- 
present the  ossified  ligamentous  fibres  of  the  original  corium||.” 

Summary. — The  facts  described  in  this  communication  will,  I trust,  be  regarded  as 
a valuable  addition  to  our  knowledge  of  the  osteological  structure  of  one  of  the  most 
remarkable  herbivorous  terrestrial  quadrupeds  that  ever  trod  the  surface  of  our 
planet.  With  the  exception  of  the  cranium,  sternum,  and  the  bones  of  the  fore-arm, 
carpus,  and  tarsus,  the  entire  skeleton  may  now  be  considered  as  determined.  In 
the  present  memoir  the  pectoral  arch  and  the  arm  are  for  the  first  time  described 

* Geology  of  the  South-East  of  England,  PI.  V.  t Ante,  p.  277. 

X Philosophical  Transactions,  1841,  p.  150,  Plate  X.  figs.  1,  2,  3,  4. 

§ See  Reports  on  British  Fossil  Reptiles,  1841,  p.  115. 

II  See  Wonders  of  Geology,  sixth  edition,  p.  438.  Mr.  Bowkrbank,  Mr.  Williamson,  and  other  eminent 
microscopical  observers,  to  whom  I gave  specimens  of  the  spines,  concur  in  the  statement  that  the  structure  of 
these  bones  is  identical  with  that  of  the  dermal  scutes,  Plate  XXXII.  fig.  23. 


THE  IGUANODON  AND  HYL^OSAURUS. 


285 


and  correctly  assigned,  and  the  true  characters  of  the  vertebral  column  demon- 
strated, so  far  as  the  data  hitherto  obtained  afford  the  means  of  re-connecting  its  dis- 
jointed elements. 

The  physiological  inferences  resulting  from  this  investigation  confirm,  in  every 
essential  particular,  those  which  I had  the  honour  to  submit  to  the  Society  in  my 
late  memoir  on  the  maxillary  and  dental  organs  of  the  Iguanodon.  By  the  deter- 
mination of  the  principal  bone  of  the  arm,  we  now  discover  that  the  fore-limbs  of 
the  colossal  original  were  more  reptilian  in  their  relative  proportions  with  other  parts 
of  the  skeleton,  than  could  a priori  have  been  surmised.  But  this  comparatively 
feeble  development  of  the  anterior  extremities  tends  to  confirm  the  opinion  which  I 
formerly  advanced,  that  the  fore-feet  were  long  and  slender,  and  served  as  prehensile 
instruments ; while  the  hinder  limbs  and  feet  were  strong  and  massive,  as  in  the 
Hippopotamus. 

Thus,  after  the  lapse  of  more  than  a quarter  of  a century,  I conclude  my  attempts 
to  restore  the  skeleton  of  the  gigantic  Saurian,  of  whose  former  existence  a few 
isolated  and  water-worn  teeth  were  the  sole  known  indications,  when,  in  1825,  I 
ventured  to  communicate  to  the  Royal  Society,  through  my  friend  the  late  Davies 
Gilbert,  Esq.,  P.R.S.,  “A  Notice  of  the  Teeth  of  an  unknown  Herbivorous  Reptile 
discovered  in  the  Strata  of  Tilgate  Forest  in  Sussex.” 

19  Chester  Square,  Pimlico, 

\bth  January,  1849. 


Notes  on  the  V nrtebral  Column  of  the  Iguanodon. 

By  A.  G.  Melville,  M.D.,  Edin.  M.R.C.S. 

The  atlas  and  axis  of  this  gigantic  reptile  have  not  hitherto  been  discovered,  but 
we  may  expect,  as  in  the  corresponding  vertebrae  referred  to  the  Steneosaurus  rostro- 
minor  (G.  St.  Hilaire),  the  pleural  complement  of  the  axis  to  have  a double  attach- 
ment, above  to  the  superior  transverse  process  derived  from  the  base  of  the  neural 
lamina,  and  below  to  an  exogenous  tubercle — inferior  transverse  process — on  the 
lower  part  of  the  centrum  of  the  atlas,  or  in  addition,  to  the  contiguous  portion  of 
the  axis.  In  the  recent  Crocodiles,  the  cervical  rib  of  the  axis  is  displaced  from  its 
own  centrum,  and  has  an  upper  and  lower  attachment  to  the  odontoid  process  or 
true  centrum  of  the  atlas.  It  will  be  a matter  of  great  interest  to  ascertain  if  in  any  of 
the  extinct  Crocodilidse  or  Dinosauria,  the  rib-like  processes  of  the  atlas  are  attached 
to  their  proper  centrum,  and  not  displaced  forwards  on  the  heemal  element  of  the 
occipital  vertebra,  or  so-called  body  of  the  atlas,  as  in  the  existing  Crocodiles ; a dis- 
placement which  repeats  the  normal  attachment  of  the  ribs  in  fishes  to  the  inferior 
or  haemal  elements  of  the  bodies  of  the  vertebrae. 

2 p 


MDCCCXLIX. 


286 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


The  posterior  surface  of  the  body  of  the  axis  must  be  deeply  concave,  as  we  shall 
presently  see. 

The  large  cervical  vertebrae  from  the  Wealden  strata,  with  reversed  convexo-concave 
joints  {Streptospondylus  major,  O.),  (Plate  XXVIII.  fig.  4),  enter  into  the  composition 
of  the  cervical  region  of  the  spinal  column  of  the  Iguanodon.  We  are  forced  to  this 
conclusion  by  the  following  circumstances: — 1st,  an  anterior  dorsal  vertebra  (Plate 
XXVIII.  fig.  5.)  from  the  same  deposits,  with  similar  but  less  marked  deviations  in  the 
form  of  the  articular  facets,  and  with  a configuration  of  the  neural  arch,  so  far  as  per- 
fect, identical  with  that  existing  in  more  posterior  dorsal  vertebrse  with  plano-concave 
joints,  well-recognized  as  belonging  to  this  great  herbivorous  reptile,  links  together 
these  apparently  discrepant  vertebral  types : 2ndly,  the  amount  of  variation  here 
assumed  is  parallel  to  that  which  exists  in  its  affine  among  the  Crocodilidae,  the 
Steneosaurus  rostro-minor*  ; and  similar  changes  in  the  form  of  corresponding  arti- 
cular facets  occur  in  the  spinal  column  of  the  Ruminants,  Solipeds,  and  other  Pa- 
chyderms: Srdly,  other  alterations  in  the  sculpturing  of  the  neural  arch  of  equal 
value  with  the  modifications  in  the  form  of  the  articular  aspects  of  the  body,  are  con- 
comitant with  these  changes  in  the  different  vertebrae  just  mentioned,  and  are 
equalled  in  kind  and  degree  by  those  which  occur  in  the  series  of  neural  arches  of 
the  spine  in  the  recent  Crocodiles:  4thly,  these  convexo-concave  cervical  vertebrae 
are  found  in  such  collocation  with  other  well-determined  bones  and  vertebrae  of  the 
Iguanodon  as  to  leave  no  reasonable  doubt  of  their  belonging  to  that  animal : 
5thly,  the  number  of  these  vertebrae  of  different  ages  and  sizes  in  our  collections  is 
such  as  we  might  have  expected  on  that  supposition ; and  6thly,  if  these  be  not  the 
cervical  vertebrae  of  the  Iguanodon,  we  have  the  (assumed)  Streptospondylus  major 
with  nothing  but  a neck,  whilst  the  Iguanodon,  as  yet  known,  is  wholly  destitute  of 
that  region  of  the  spine : is  it  not,  therefore,  more  probable  that  the  neck  of  the  so- 
called  Streptospondylus  belongs  of  right  to  the  Iguanodon,  especially  as  the  bones  of 
that  reptile,  tested  by  the  fortunate  discovery  of  the  Maidstone  specimen,  constitute 
the  great  majority  of  the  osseous  relics  from  the  deposits  of  the  Weald  ? in  other 
words,  the  Iguanodon  is  the  reptile  par  excellence  characteristic  of  the  Wealden 
formation. 

The  Streptospondylian  form  of  the  body  of  a vertebra  can  no  more  characterize 
a genus  of  Reptiles  than  the  Amphicoelian  or  Coelospondylian  modifications  ; each  is 
common  to  a group  of  species  constituting  not  only  distinct  genera  and  families,  but 
also  orders  and  subclasses.  Nay,  the  Streptospondylian  type  is  not  even  persistent 
throughout  the  elements  of  the  same  spinal  column ; it  disappears  towards  the 
middle  of  the  dorsal  region  in  the  Steneosaurus  rostro-minor,  the  best  known  example 
of  this  structure,  and  that  in  which  it  was  first  recognized  by  Baron  Cuvier.  The 
genus  Streptospondylus  of  V.  Meyer  ought  therefore  to  be  abolished,  and  the  resi- 
dual generic  appellation  Steneosaurus  (G.  St.  Hilaire)  be  retained  to  designate  Cu- 

* Vide  Cuvier,  Oss.  Fossiles,  vol.  ix.  8vo  edit. 


THE  IGUANODON  AND  HYL^OSAURUS. 


287 


vier’s  first  Gavial  of  Honfleur.  The  Amphicoelian  and  Procoeiian  forms  are  gene- 
rally continued  through  the  whole  length  of  the  vertebral  column;  the  Streptospon- 
dylian  modification  in  the  last  sacral  replaces,  and  in  the  first  caudal  is  superadded 
to,  the  Procoeiian  form  of  the  vertebral  bodies  characteristic  of  the  living  Crocodiles. 

In  the  Report  on  British  Reptiles  much  stress  is  laid  on  the  uniformity  in  length 
of  the  bodies  of  the  same  vertebral  series  in  Reptiles ; this  indeed  holds  good  within 
certain  limits  among  the  less  complicated  smaller  existing  Lacertse,  but  will  lead 
us  into  error  if  rigidly  applied  to  the  more  highly  organized  extinct  Saurians  and 
Crocodiles.  The  relative  length  of  the  vertebra  must  always  be  taken  exclusively 
of  the  articular  convexity,  whether  that  be  in  front  or  behind,  as  is  the  practice  in 
stating  the  absolute  length  of  the  spine  or  of  its  individual  regions.  Deterred  by  the 
great  length  of  these  cervical  vertebrse  referred  to  the  Streptospondylus  major,  when 
compared  with  the  shortness  of  the  dorsal  or  lumbar  vertebrse  assigned  by  him  to  the 
Cetiosaurus  brevis,  Professor  Owen  was  unwilling  to  associate  them  together  as  be- 
longing to  the  spinal  column  of  the  same  species,  which,  however,  appears  to  be 
really  the  case,  as  I shall  afterwards  have  occasion  to  demonstrate. 

The  body  of  the  cervical  vertebra,  Plate  XXVIII.  fig.  4,  though  somewhat  crushed, 
well  displays  the  peculiar  characters  of  this  region  of  the  spine.  Its  dimensions  are 
as  follow : — 

inches. 

Length  of  body  between  the  centres  of  the  articular  facets  . . . 3f 

Extreme  length,  including  convexity 5^ 

Length  of  body  (inferiorly),  exclusive  of  convexity  ..... 

Height  of  body  posteriorly  3^ 

Width  of  posterior  concave  surface 5 

Extent  from  the  extremity  of  one  transverse  process  to  the  other.  9 
Transverse  diameter  of  the  spinal  canal if 

The  centrum  (a)  is  depressed,  and  yields  a subpentangular  section  with  the  apex 
below;  it  is  broader  than  high,  but  the  width  is  nearly  equal  to  the  length.  The 
anterior  articular  facet  («')  is  convex,  the  posterior  (a")  deeply  concave  with  thin 
edges ; both  have  a wide  oval  contour.  The  lateral  aspect  presents  a deep  concavity 
beneath  the  root  of  the  neural  lamina,  bounded  inferiorly  by  a ridge  (e)  faint  and  ex- 
panding behind,  but  developed  in  its  anterior  third  or  half  into  a flat  oblong  facet  (per- 
apophysis),  for  articulation  with  the  head  of  the  rib.  Below  the  transverse  ridges  the 
surfaces  of  the  opposite  sides,  concave  outwards,  rapidly  converge  to  a broad  median 
Carina  widening  behind,  which  does  not  appear  to  be  developed  downwards  in  front 
into  a distinct  spine  as  in  Crocodiles.  How  much  of  the  body  is  contributed  by  the 
expanded  bases  of  the  neural  laminm  cannot  be  readily  determined,  the  sutures  being 
obliterated ; from  the  great  width  of  the  vertebral  foramen  in  the  neck,  it  is  most 
probable  that  they  do  not  meet  mesially,  and  exclude  the  centrum  from  entering 
into  the  composition  of  that  foramen,  as  is  the  case  in  the  dorsal  region  of  the  spine. 

2 p 2 


288 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


The  neural  lamina  (b)  contracts  above  its  base,  and  again  slightly  expands  ere  it 
coalesces  with  its  fellow,  the  posterior  notch  as  usually  being  the  deepest ; a small 
tract  of  the  body  is  also,  as  it  were,  left  uncovered  in  front  and  behind  to  nearly  as 
great  an  extent  as  in  the  lumbar  vertebrae  hitherto  assigned  to  the  Cetiosaurus  brevis-, 
this  character  therefore  is  of  no  value  either  generically  or  specifically.  The  spine 
{neuracantha)  is  represented  only  by  a ridge  contracting  and  subsiding  towards  the 
anterior  edge  of  the  neural  arch.  The  strong  sub-prismatic  upper  transverse  process 
{d)  {plagiapophysts)  springs  from  the  upper  part  of  the  neural  lamina  {neuropoma), 
and  curves  backwards,  bending  slightly  downwards  towards  its  outer  extremity, 
which  furnishes  a large  articular  rounded  surface  for  the  tubercle  of  the  rib.  In- 
ternally it  is  cut  away  obliquely  downwards  and  inwards  for  the  lodgement  of  the 
posterior  oblique  process  {met-arthrapophysis)  which  lies  between  it  and  the  crown 
of  the  neural  arch,  resting  on  the  oval  articular  facet  {f)  of  the  anterior  oblique  pro- 
cesses (pro-arthrapophysis),  which  is  thus  situated  on  the  upper  surface  of  the  trans- 
verse process ; those  of  opposite  sides  are  widely  separate,  look  towards  each  other, 
and  are  only  inclined  slightly  towards  the  horizon,  their  inner  margins  being  sepa- 
rated by  a narrow  groove  from  the  sides  of  the  neural  laminae. 

The  long,  thick  and  compressed  peduncles  of  the  posterior  oblique  processes  (g), 
spring  from  the  hinder  border  of  the  neural  arch  on  each  side  of  the  mesial  line,  and 
diverge  as  they  pass  backwards,  projecting  much  beyond  the  articular  cup  of  the 
body.  Their  section  is  ovate,  the  lower  edge  being  the  thickest ; each  is  slightly 
twisted  on  its  axis  towards  the  extremity,  which  is  bevelled  off  obliquely  to  the  upper 
margin  for  the  oval  articular  surface,  looking  downwards  and  slightly  outwards. 

We  may  conjecture  that  this  vertebra  is  one  of  the  most  posterior  cervical  from 
the  high  origin  of  the  transverse  process,  for  in  the  series  of  five  vertebrae  behind  the 
atlas  and  axis  in  the  Crocodile,  this  process  rises  gradually  from  the  base  of  the 
neuropome  to  the  middle  of  its  height,  and  reaches  the  crown  of  the  neural  arch  at 
the  third  dorsal. 

The  large  vertebra  with  a wedge-shaped  body  and  convexo-concave  articular  facets, 
Plate  XXVIII.  fig.  5,  we  regard  as  one  of  the  more  anterior  of  the  dorsal  region  of 
the  spine ; in  it  the  inferior  transverse  process  has  abandoned  the  side  of  the  cen- 
trum, and  is  placed  on  that  of  the  neural  lamina.  In  the  first  dorsal  of  the  Croco- 
dile, the  perapophysis  is  still  below  the  neuropomal  suture;  in  the  third  and  fourth, 
the  corresponding  surface  is  subdivided  by  that  sutural  line ; and  in  the  fifth  it  quits 
the  centrum  altogether,  but  is  not  placed  on  the  side  of  the  neural  arch.  No  speci- 
men has  yet  been  met  with  of  a dorsal  vertebra  belonging  to  the  Iguanodon  with  the 
perapophysial  surface  or  tubercle  wholly  or  partially  on  the  centrum,  although  that 
character  may  have  been  presented  by  the  two  or  three  first  dorsal. 

The  anterior  convexity  (a')  of  the  above-mentioned  vertebra  is  much  less  deve- 
loped than  in  the  cervical,  and  the  concavity  behind  {a”)  is  correspondingly  shallow. 
The  section  of  the  body  would  present  a deep  triangular  outline  with  the  apex  below 


THE  IGUANODON  AND  H YL.EOSAURUS. 


289 


corresponding  to  a thick  median  crest.  The  body  is  constricted  in  the  centre  so  that 
the  sides  are  concave  parallel  to  its  axis,  but  convex  vertically,  owing  to  the  great 
prominence  of  a broad  longitudinal  ridge,  equivalent  to  that  bearing  the  perapophy- 
sial  surface  in  the  cervical ; above  and  below  which  there  is  also  a deep  concavity. 
The  spinal  canal  {j)  has  a transversely  oval  outline,  and  enlarges  considerably 
towards  each  extremity.  The  neural  lamina  {h)  contracts  suddenly,  though  slightly, 
and  chiefly  from  behind  forwards  above  its  expanded  base,  so  that  the  posterior  notch 
is  much  the  deeper;  its  external  surface  is  impressed  by  a deep  and  rough  irregular 
fossa  (/)  for  the  insertion  of  the  head  of  the  rib,  bounded  behind  by  a sharp  pro- 
minent ridge  ascending  obliquely  forwards  from  near  the  posterior  and  inferior  angle 
of  the  base  of  the  neuropome,  and  passing  outwards  on  the  under  surface  of  the 
plagiapophysis  {d).  In  front,  this  perapophysial  surface  (/)  is  deflned  by  a thin 
margin  arching  backwards  to  meet  the  above-mentioned  buttress-like  ridge  at  the 
root  of  the  transverse  process,  which  is  detached,  but  springs  with  an  inclination 
upwards  from  the  side  of  the  spinal  platform.  The  spinous,  anterior,  and  posterior 
oblique  processes,  are  unfortunately  wanting;  but  the  anterior  oblique  processes 
do  not  approximate  to  each  other  so  closely  as  in  the  more  posterior  vertebrae,  in 
which  they  are  merely  separated  by  the  trenchant  anterior  edge  of  the  spine ; from 
this  we  may  infer  that  the  long  peduncles  of  the  met-arthropophyses  in  the  cervical 
vertebrae  have  coalesced  at  their  bases  to  support  the  more  strongly  developed  spine, 
but  that  their  apices  bearing  the  articular  facets  are  still  separated  by  a wide  notch, 
more  or  less  filled  up  by  the  base  of  the  neuracantha  (c),  which  decreases  in  width  as 
it  extends  forwards  to  the  anterior  edge  of  the  neural  arch  ; its  line  of  attachment 
sweeping  downwards  at  the  same  time  from  the  excavation  of  the  spinal  platform  in 
front  for  the  reception  of  the  oblique  processes  of  the  preceding  vertebra.  The  ex- 
panded bases  of  the  neural  laminae  are  defined  by  the  direction  of  the  superficial 
striae,  and  doubtless  coalesce  more  or  less  completely  in  the  mesial  line,  commencing 
in  front,  to  exclude  the  centrum  from  any  share  in  the  formation  of  the  vertebral 
canal.  The  dimensions  of  this  most  instructive  specimen  are  subjoined. 

inches,  lines. 


Length  of  the  body  between  the  centres  of  the  articular  surfaces  . 4 3 

Greatest  width  of  body 4 3 

Greatest  height  of  body 6 6 

Antero-posterior  diameter  of  neural  lamina  where  narrowest  . . 2 9 

Width  of  spinal  canal 1 9 

Height  of  spinal  canal 1 4 


The  next  vertebra  to  be  described,  Plate  XXIX.  fig.  8,  differs  from  that  just  men- 
tioned, in  the  flatness  of  the  anterior  articular  surface  (a'),  and  in  the  almost  com- 
plete obliteration  of  the  posterior  concavity  («"),  in  the  less  central  constriction  of 
the  body,  and  in  the  absence  of  its  inferior  median  ridge.  Notwithstanding  the  situa- 
tion of  the  perapophysial  surface  on  the  side  of  the  neuropome,  the  above  characters 


290 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


all  point  to  a more  posterior  position  in  the  dorsal  series;  and  we  may  suppose 
either  that  the  anterior  convexity  of  the  body  subsided  much  more  rapidly  than  the 
head  of  the  ribs  changed  its  point  of  attachment,  or  that  several  vertebrae  presenting 
a similar  configuration  of  the  neural  arch,  but  with  a progressively  diminishing 
convexity,  occurred  at  the  anterior  part  of  the  dorsal  region,  which  would  indicate  a 
less  rapid  transition  between  the  different  forms  of  the  vertebrae,  and  consequently 
a greater  number  of  them  than  in  the  Crocodiles,  which  might  indeed  have  been 
expected  in  a herbivore  with  a bulky  trunk,  as  shown  by  the  huge  ribs  in  the  Man- 
tellian  collection. 

The  dimensions  of  this  very  perfect  and  interesting  fossil  are  as  follow : — 


inches,  lines. 


Extreme  length  of  the  body 4 3^ 

Extreme  width  of  the  body 3 3 

Extreme  height  of  body  (measured  on  anterior  surface)  . ...  4 10 

Antero-posterior  diameter  of  neural  lamina  where  narrowest  . . 2 9 

From  mesial  line  anteriorly  to  extremity  of  transverse  process . . 8 

Antero-posterior  diameter  of  transverse  process  at  root  ....  2 9 

Between  extreme  points  of  anterior  oblique  processes  ....  3 4 

Width  of  spinal  canal  (posteriorly) 1 2 


The  body  is  much  contracted  in  the  centre,  so  that  the  sides  are  deeply  concave 
lengthwise,  but  convex  vertically ; they  converge  towards  each  other  below,  thus  a 
vertical  section  presents  a wedge-shaped  outline  with  convex  sides.  The  neuropo- 
mal  sutures  are  obliterated,  but  the  share  contributed  to  the  body  by  the  expanded 
bases  of  the  neural  laminae  is  equal  to  that  indicated  by  the  detached  neural  arch  in 
Mr.  Saull’s  collection.  The  neural  lamina  (/)  is  coextensive  Muth  the  supporting 
centrum,  but  it  contracts  slightly  as  it  ascends,  and  so  that  the  posterior  notch  is 
still  the  deepest.  The  spinal  platform  is  also  excavated  in  front  for  the  reception  of 
the  posterior  oblique  processes  ; the  base  of  the  spine  (c)  increases  in  thickness  as  it 
passes  backwards  and  rises  on  the  thick  hinder  portion  of  the  platform.  The  anterior 
articular  facets  (/*)  are  oval,  look  towards  each  other,  and  their  inferior  margins  meet 
nearly  at  right  angles,  separated  only  by  a slight  notch,  and  further  back  by  the  thin 
anterior  edge  of  the  spine.  The  strong  trihedral  transverse  processes  pass  outwards  and 
upwards  with  an  inclination  backwards  from  the  sides  of  the  spinal  platform,  and  are 
as  it  were  twisted  on  their  axes,  so  that  the  upper  surface  slopes  forwards  and  down- 
wards internally,  but  backwards  and  downwards  externally ; both  edges  are  thin  ; be- 
low it  is  supported  by  a more  strongly  developed  diagonal  buttress-like  ridge,  passing 
outwards  beneath,  and  gradually  subsiding  into  the  transverse  process,  giving  it  an 
increased  thickness.  This  ridge  separates  two  fossae  on  the  free  aspect  of  the  neuro- 
pome ; the  anterior  is  more  or  less  obliterated  by  a rough  excrescence,  which  articu- 
lates with  the  head  of  the  rib  (/) ; the  posterior  is  remarkably  deep,  partly  roofed 
over  by  the  base  of  the  plagiapophysis,  and  separated  from  that  of  the  opposite  side 


THE  IGUANODON  AND  HYL^OSAURUS. 


291 


by  the  pinched  up  lower  edge  of  the  coalesced  peduncles  of  the  rnet-arthrapophyses, 
which  are  unfortunately  detached.  The  spinal  canal  is  nearly  circular,  and  expands 
slightly  in  front,  where  it  assumes  a transversely  oval  outline. 

In  a corresponding  anterior  dorsal  vertebra.  No.  2160  of  the  Mantellian  Collection, 
Plate  XXVIll.  fig.  7,  belonging  to  a younger  and  smaller  individual,  the  posterior 
articular  processes  are  present  (g),  and  the  perapophysial  surface  (/)  is  well-defined, 
but  has  in  the  Report  on  British  Reptiles  been  regarded  as  the  base  of  the  transverse 
process,  whilst  the  true  origin  {d)  of  that  process  is  stated  to  be  ‘ the  rough  external 
free  border’  of  the  spinal  platform,  ‘probably  fractured.’  A comparison  of  figs.  7 
and  8 will  remove  any  doubt  as  to  the  accuracy  of  the  interpretation  here  adopted. 
The  wedge-shaped  form  of  the  centrum  in  the  above-mentioned  vertebrae  cannot  be 
regarded  of  higher  value  than  as  indicating  their  anterior  position  in  the  dorsal  series ; 
in  the  Crocodile,  the  compression  of  the  centrum  and  the  development  of  an  inferior 
carina  ceases  in  the  fifth  dorsal,  in  which  also  the  head  of  the  rib  is  attached  to  a 
facet  on  the  transverse  process  a little  external  to  its  base,  while  the  tubercle  is  fixed  to 
its  extremity,  as  is  the  case  in  the  vertebra,  Plate  XXIX.  fig.  9 ; which  from  its  close 
resemblance  to  those  just  described  we  have  ventured  to  assign  to  the  Iguanodon, 
notwithstanding  those  slight  modifications  which  have  induced  Professor  Owen  to 
regard  similar  ones  as  belonging  to  the  genus  Cetiosaurus,  but  which  we  believe  to 
be  simply  indicative  of  position  in  the  same  vertebral  column,  as  we  have  wholly 
failed  in  detecting  any  such  differential  characters,  after  repeated  examination,  as 
would  warrant  us  in  considering  this  vertebra  as  specifically,  and  still  less  generi- 
cally,  distinct. 

This  vertebra  (Plate  XXIX.  fig.  9)  differs  from  those  above  described  in  the  relative 
shortness  and  in  the  cylindrical  form  of  the  body,  which  is  much  constricted  in  the 
centre,  so  that  the  surfaces  are  deeply  concave  parallel  to  the  axis,  but  convex  in  the 
opposite  direction.  Its  length  is  3 inches  6 lines ; the  width  of  its  anterior  subcircular 
articular  facet  is  6 inches  1 line,  inclusive  of  the  thick  rough  everted  edge,  and  its 
height  5 inches  4 lines.  The  posterior  surface  is  transversely  oval ; both  surfaces  are 
somewhat  concave,  but  the  hinder  more  distinctly  so,  especially  in  its  upper  half,  whilst 
the  corresponding  part  of  the  anterior  aspect  is  raised  into  a faint  mesial  convexity ; 
the  adjacent  surfaces  of  contiguous  vertebrae  are  thus  coadapted.  The  spinal  canal 
is  1 inch  1 line  transversely  where  narrowest,  but  enlarges  anteriorly.  The  neuro- 
pomal  sutures  are  obliterated,  but  the  direction  of  the  superficial  striae  or  rugosities 
indicate  the  great  expansion  of  the  bases  of  the  neural  laminae,  which  leave  only  a 
narrow  tract  widening  behind  the  centrum  to  form  the  floor  of  the  spinal  canal. 
The  neuropome  rises  from  its  base  nearer  the  anterior  than  the  posterior  surface,  and 
thus  the  intervertebral  foramen  is  chiefly  constituted  by  the  posterior  notch.  Where 
most  contracted  the  neural  lamina  measures  2 inches  6 lines  in  antero-posterior  ex- 
tent, at  its  base  it  is  2 inches  10  lines;  seven  lines  of  the  body  are  left  exposed 
behind,  and  about  three  in  front.  But  who  will  venture  to  base  generic  distinctions 
on  such  trivial  characters  as  these  ? The  enormous  spine  rises  from  nearly  the  whole 


292 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


length  of  the  platform,  which  presents  a median  notch  in  front,  separating  the  pro- 
jecting anterior  oblique  processes,  whose  oval  facets  are  almost  horizontal,  being  in- 
clined to  each  other  only  at  a very  obtuse  angle.  The  strong  transverse  processes 
project  outwards,  with  a slight  inclination  upwards  from  its  lateral  edges,  their  upper 
surfaces  sweeping  gently  upwards  to  the  lateral  aspects  of  the  spine.  The  antero- 
inferior edge  of  the  plagiapophysis  is  thick,  and  about  2 inches  external  to  its  base 
bears  the  rough  facet  for  the  head  of  the  rib  (/),  beyond  which  this  process  contracts 
suddenly  in  antero-posterior  extent  to  lodge  the  neck  of  the  rib ; its  extremity  is 
however  lost.  The  thickness  of  the  transverse  process  diminishes  to  its  posterior 
edge,  and  below  the  diagonal  buttress  already  mentioned  in  the  preceding  descrip- 
tions, supports  it,  and  is  prolonged  outwards  on  the  slender  portion  of  the  process. 
The  posterior  deep  fossa  behind  the  buttress  exists  also,  but  the  anterior  is  obliterated, 
the  outer  surface  of  the  neural  lamina  being  only  slightly  convex  from  before  back- 
wards, and  subconcave  vertically. 

The  spine  ascends  obliquely  backwards  and  is  of  nearly  equal  width  throughout; 
in  its  basal  half  it  diminishes  rapidly  in  thickness  towards  its  anterior  thin  margin, 
which  is  prolonged  forwards  to  the  edge  of  the  platform  ; in  its  upper  moiety  it  con- 
tracts slightly  behind  ; the  posterior  border  presents  a deep  groove,  obliterated  in  the 
upper  third  by  a rough  ridge  rising  from  its  floor ; the  apex  is  broadly  truncated  and 
the  hinder  angle  removed  ; the  anterior  border  is  carinate  below,  but  above  exhibits 
a well-marked  excavation,  becoming  wider  and  deeper  above.  The  greatest  diameter 
of  the  transverse  process  at  its  root  is  2 inches  9 lines  ; between  the  articular  surfaces 
of  opposite  sides,  for  the  head  of  the  rib,  it  measures  8 inches  5 lines.  The  length  of 
the  spine  anteriorly  is  12  inches  5 lines,  its  greatest  antero-posterior  diameter  is 
3 inches  4 lines,  and  its  greatest  thickness  2 inches  3 lines.  The  greatest  width  of 
the  centrum  is  equal  to  4 inches  5 lines.  The  extreme  height  of  this  vertebra  is 
1 foot  8 inches. 

Undoubted  lumbars  of  the  Iguanodon  have  not  hitherto,  so  far  as  1 am  aware,  been 
recognized,  although  some  of  the  vertebrae  preserved  in  the  Maidstone  specimen 
may  belong  to  that  region  of  the  spine.  The  presence  of  an  articular  facet  on  the 
transverse  process  for  the  attachment  of  the  rib  is  the  distinctive  character  between 
the  posterior  dorsal  and  lumbar  vertebra ; unfortunately  these  processes  being  readily 
detached  are  usually  absent.  However,  we  may  expect  certain  modifications  in  the 
neural  arch  of,  and  also  a more  robust,  perhaps,  shorter  body  in,  the  vertebrae  of  the 
lumbar  region.  As  in  Crocodiles,  the  transverse  processes  would  continue  to  spring 
at  the  level  of  the  spinal  platform,  but  the  absence  of  the  rib  would  cause  a further 
simplification  in  the  sculpturing  of  the  neural  lamina,  and  thus  the  supporting  dia- 
gonal buttress  of  the  transverse  process  would  wholly  disappear.  The  neural  laminae 
themselves  would  have  a less  antero-posterior  extent  than  in  the  more  anterior  ele- 
ment of  the  column,  and  hence  the  notches  and  uncovered  tracts  of  the  body  would  be 
more  marked  than  in  the  dorsal  vertebrae,  where  great  strength  and  size  are  required 
in  the  arch  to  support  the  huge  ribs  of  this  herbivorous,  and  it  may  be,  ruminating 


THE  IGUANODON  AND  H YL^EOSAURUS. 


293 


Saurian.  Moreover,  the  nerves  escaping  through  the  intervertebral  foramina  of  this 
region  are  larger  than  those  of  the  dorsal  segment  of  the  spine,  as  they  contribute  to 
the  formation  of  the  lumbar  and  sacral  plexuses ; the  vertebral  foramen  would  pro- 
bably also  be  wider,  since  the  spinal  chord  enlarges  in  that  region  to  form  the  pos- 
terior expansion  or  ganglion  of  the  sinus  rhomboidalis,  which  extends  through  the 
anterior  half  of  the  canal  of  the  sacrum : the  expanded  bases  of  the  neural  laminae 
would  therefore  leave  a portion  of  the  centrum  uncovered  mesially,  to  form  the  floor 
of  the  canal  and  support  directly  the  medulla  spinalis. 

I can  perceive  no  difference  between  the  posterior  dorsal  or  lumbar  vertebrae 
(No.  2133,  2115)*  assigned  by  Professor  Owen  to  the  Cetiosaurus  brevis,  atidthat  last 
described  as  corresponding  in  some  respects  to  the  fifth  dorsal  in  the  spinal  column 
of  the  Crocodile,  than  a diminution  in  the  relief  of  the  buttress  supporting  the  trans- 
verse process.  In  No.  2115  the  neural  arch  is  broken  away,  and  the  tract  of  the 
centrum  left  uncovered  behind  to  form  the  floor  of  the  intervertebral  foramen,  is  of 
greater  extent  than  in  No.  2133,  indicating  a more  posterior  situation  in  the  vertebral 
series.  The  approach  to  the  quadrangular  form  of  the  body  of  this  vertebra  is  no 
proof  whatever  of  a specific  and  still  less  of  a generic  distinction  ; otherwise  the  first 
sacral  vertebra,  which  is  more  decidedly  quadrate,  if  found  separate,  would  be 
equally  entitled  to  a generic  value  ; but  its  association,  in  the  sacrum  from  Mr.  Saull’s 
collection  (Plate  XXVI.),  with  other  vertebral  bodies  of  a very  dissimilar  character, 
and  with  the  ilium  of  the  Iguanodon,  prevents  our  falling  into  an  error  of  such 
magnitude.  We  may  therefore  reasonably  conclude,  that  these  vertebrae,  to  wit, 
Nos.  2133,  2 155,  belong  to  the  Iguanodon,  and  that  the  latter,  in  the  form  of  the  body, 
approached  the  first  sacral,  and  was  one  of  the  proper  lumbar  series.  The  vertebra. 
No.  2109,  attributed  in  the  above-mentioned  report  to  the  (so-called)  second  species 
of  Cetiosaurus  found  in  the  Wealden  formation  {C.  brachyurus),  is  also  a posterior 
dorsal  or  lumbar  vertebra  of  the  Iguanodon  ; the  neural  arch  is  much  mutilated.  The 
only  other  element  of  the  skeleton  of  that  species  is  a caudal  vertebra.  No.  2161, 
which  also  belongs  to  the  Iguanodon ; being  in  fact  one  of  the  most  anterior  of  the 
caudal  series,  and  contrary  to  the  character  of  the  genus  to  which  it  was  referred,  it 
presents  one  of  the  most  interesting  and  instructive  examples  of  the  rough  surface  on 
the  sides  of  the  upper  aspect  of  the  centrum,  left  by  the  removal  of  the  unanchylosed 
neural  arch.  The  so-called  Cetiosaurus  brevis  being  thus  founded  only  on  two  ver- 
tebrae which  belong  to  the  Iguanodon,  must  be  expunged  from  the  list  of  extinct 
reptiles. 

The  angular  posterior  caudal  vertebrae  referred  in  the  Report  on  British  Reptiles, 
to  the  Cetiosaurus  brevis,  I am  also  inclined  to  assign  to  the  Iguanodon  for  the  fol- 
lowing reasons; — 1st,  a similar  vertebra,  as  far  as  can  be  ascertained,  exists  in  the 
Maidstone  specimen,  and  in  this  case  an  admixture  of  bones  of  distinct  animals 
cannot  even  be  suspected;  2ndly,  the  numerical  ratio  of  the  vertebrae  of  this  kind 

* Mantellian  Collection  in  the  British  Museum. 

MDCCCXLIX.  2 Q 


294 


DR.  MANTEL L ON  THE  OSTEOLOGY  OF 


occurring  in  the  Wealden,  to  those  from  the  same  deposits  and  localities  belonging 
to  other  regions  of  the  spinal  column,  all  referable  to  the  Iguanodon,  excepting  the 
few  megalosaurian  and  crocodilian  vertebrse,  is  such  as  long  ago  to  have  induced 
Dr.  Mantell  to  regard  them  as  characteristic  of  that  Saurian  ; and  the  occurrence 
of  such  vertebrse  with  those  of  the  sacrum  and  other  bones  of  the  Iguanodon  in 
Western  Sussex,  described  by  Cuvier,  has  already  been  commented  on*-.' — 3rdly, 
as  I shall  presently  show  that  the  four  large  anterior  caudal  vertebrse  in  the  Man- 
tellian  Collection,  also  assigned  by  the  author  of  the  Report  to  the  Cetiosaurus  hrevis, 
cannot  be  transmuted  into  the  vertebrse  in  question  by  any  changes  occurring 
in  a consecutive  series,  there  is  left  for  that  animal  only  some  terminal  caudal  verte- 
brse ; while  to  complete  the  tail  of  the  Iguanodon  just  those  are  wanting;  4thly,  but 
independently  of  the  evidence  furnished  by  the  Maidstone  specimen,  we  have  seen 
examples  which  point  out  the  series  of  changes  by  which  these  angular  vertebrse  are 
produced  from  those  of  the  middle  caudal  region.  These  changes,  again,  are  not 
greater  than  those  that  take  place  in  the  tail  of  the  Hylseosaurus'l-  and  other  extinct 
reptiles,  as  well  as  in  that  of  many  mammalia.  * 

Let  us  look  for  a moment  at  the  vertebrse  of  the  tail  of  the  Mosasaurus  as  con- 
trasted with  those  of  other  regions  of  the  spinal  column  in  that  reptile,  and  we  shall 
then  be  prepared  to  admit  far  greater  modifications  than  are  here  assumed.  Could 
we  a priori  correctly  restore  the  vertebral  column  of  any  animal  from  scattered 
fragments,  belonging  to  different  individuals,  without  making  allowance  for  the 
changes  occurring  in  the  series  of  segments  composing  that  column  ? 

In  the  form  of  the  terminal  caudal  vertebrse  we  may  expect  to  find  a very  great 
similarity  even  in  remote  genera,  and  hence  it  is  unsafe  to  base  a generic  character 
on  their  peculiarities.  The  genus  Cetiosaurus  (restricted  to  the  species  mediiis  and 
longus  from  the  oolite)  is  founded  chiefly  on  such  trivial  distinctions,  and  we  may 
refer  to  it  any  caudal  vertebra  of  considerable  dimensions  with  plano-concave  or 
biconcave  facets  not  referable  to  other  known  and  perfectly  determined  genera,  such 
as  the  Ichthyosaurus  and  Plesiosaurus,  of  which  we  have  fortunately  nearly  perfect 
skeletons,  and  hence  cannot  be  led  astray  in  the  labyrinth  of  fragments  from  which 
we  are  compelled,  in  most  instances,  to  construct  the  lost  denizens  of  tlie  former 
lands  and  seas  of  our  globe. 

In  the  caudal  vertebrae  of  the  Iguanodon,  the  body  is  wedge-shaped;  the  sides, 
which  are  faintly  concave  lengthwise  and  flat,  or  but  slightly  convex  vertically,  con- 
verge towards  each  other  below;  in  the  three  or  four  most  anterior,  they  present  a 
concavity  beneath  the  base  of  the  short  caudal  rib,  which  is  wedged  between  the  cen- 
trum and  the  root  of  the  neural  lamina  ; in  a very  instructive  example  in  Dr.  Mantell’s 
Collection,  the  pleural  element  has  dropped  out  from  one  side,  leaving  a deep  cavity 
now  filled  by  matrix;}:.  The  caudal  ribs  disappear  towards  the  middle  of  the  tail,  after 
which  the  bodies  of  the  vertebrse  have  a subhexagonal  form,  Plate  XXX.  figs.  12,  13  ; 

* Ante,  p.  277.  t See  Plate  XXXII.  % Philosophical  Transactions,  1841,  Plate  VIII.  fig.  37  o. 


THE  IGUANODON  AND  H YL^OSAURUS. 


295 


the  angles  of  the  upper  or  basal  surface  of  the  eentriini,  which  support  the  impacted 
roots  of  the  ribs,  are  therefore  removed,  and  replaced  by  planes  converging'  towards 
each  other  above,  and  forming  with  the  primary  surfaces  a longitudinal  ridge  on  each 
side,  which  descends  gradually  to  its  centre  in  the  terminal  vertebrae,  at  the  same 
time  becoming  more  prominent  as  the  body  assumes  a more  hexagonal  figure.  In 
the  vertebrae  immediately  adjoining  the  sacrum,  the  anterior  articular  surface  is 
flat  or  slightly  concave  in  its  lower  moiety,  but  convex  above,  whilst  behind  the 
reverse  is  the  case,  and  thus  the  vertebral  surfaces  are  coadapted  ; in  the  middle 
caudal  elements,  the  body  has  plano-concave  facets  ; the  anterior  then  becoming  de- 
pressed in  the  terminal  vertebrae,  which  are  thus  biconcave.  The  expanded  bases  of 
the  neural  laminae  leave  a portion  of  the  centrum  uncovered  inesially,  above  they 
contract  and  leave  considerable  tracts  of  the  body  exposed ; the  posterior  notch  is 
twice  the  depth  of  the  anterior.  The  elongated  space  ascends  obliquely  backwards, 
increasing  in  width,  but  is  abruptly  truncated  ; the  hinder  border  is  in  its  upper  half, 
while  from  the  lower  moiety  of  the  anterior  margin  a thin  plate  extends  forwards,  its 
base  reaching  to  the  deep  notch  which  separates  the  pro-arthrapophyses ; these  re- 
ceive between  them  the  closely  approximated  corresponding  posterior  processes  which 
look  outwards,  and  are  developed  on  the  hinder  part  of  the  base  of  the  spine,  their 
thin  posterior  edge  being  separated  by  a shallow  notch.  The  free  aspect  of  the  neu- 
ropome is  flat  in  the  axis  of  the  vertebra,  but  concave  in  the  opposite  diameter,  the 
concavity  passing  upwards  into  the  lateral  surface  of  the  spine. 

Tbe  spinal  canal  is  circular,  widening  slightly  at  each  extremity.  The  chevron  bone 
is  not  developed  at  the  two  first  caudal  intervertebral  spaces  in  the  fossil,  Plate  XXX. 
fig.  17,  a?,  which  represents  four  vertebrae  belonging  to  the  same  individual  as  the  frag- 
ments of  the  sacrum,  figs.  15  and  16  : there  is  a marked  increase  in  the  size  of  the  body 
to  the  third,  and  then  it  diminishes;  that  of  probably  the  second  caudal  is  but  little 
contracted  inferiorly,  whilst  in  the  third  it  is  carinate,  and  encroached  on  posteriorlv 
by  the  semicircular  surface  descending  obliquely  forwards,  and  giving  attachment  to 
the  anterior  facet  of  the  expanded  base  of  the  chevron  bone,  which  is  wedged  into  the 
intervertebral  space,  truncating  the  opposed  angles  of  the  contiguous  vertebrae.  The 
laminae  of  the  chevron  bone  (angiopoma)  coalesce  at  their  distal  extremity,  and  de- 
velope  a long  inferior  spine  {angiacanfha)  ; they  also  meet  above  the  haemal  canal  to 
form  the  expanded  wedge-like  base,  the  anterior  facet  of  which  is  the  largest.  The 
angiopomal  impressions  are  never  in  pairs,  but  always  united  into  a single  subtrian- 
gular  rough  irregular  surface,  the  posterior  of  which  is  most  extensive;  the  narrow 
tract  separating  them  is  deeply  concave  lengthwise,  carinated  in  the  more  anterior 
caudal  vertebree,  but  deeply  sulcated  in  the  more  posterior  elements.  The  chevron 
bones  are  continued  further  back  than  the  ribs,  and  the  angiopomal  impressions  are 
present  on  many  of  the  hexagonal  terminal  vertebrae ; the  posterior  are  the  largest 
and  partly  subdivided  by  a slight  median  ridge.  The  dimensions  of  the  first  caudal  of 
the  above  series  are  subjoined. 


2 Q 2 


296 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


inches,  lines. 

Height  of  anterior  surface  of  body 3 6 

Width  of  anterior  surface  of  body 3 7 

Length  of  the  body  (inferiorly) 2 1 

Width  of  spinal  canal  in  centre 5^ 


lu  the  Crocodile  the  chevron  bone  commences  at  the  second  caudal  and  termi- 
nates at  the  twentieth,  but  the  rib  eeases  at  the  fifteenth,  the  number  of  vertebrae 
composing  the  tail  being  forty-two. 

The  four  huge  caudal  vertebrae  already  mentioned  as  assigned  to  the  Cetiosaiirus 
brevis*,  exhibit  very  peculiar  characters,  fully  detailed  by  Professor  Owen,  and  are 
especially  distinguished  by  the  absence  of  projecting  posterior  articular  processes ; 
‘ the  posterior  articular  surfaces  being  impressed  upon  the  sides  of  the  posterior  part 
of  the  base  of  the  spine,’  while  the  anterior  oblique  processes  ‘ reach  beyond  the  middle 
of  the  vertebra  next  in  front,  and  pinch,  as  it  were,  the  back  part  of  the  base  of  the 
spine  so  as  to  impress  upon  it  the  surfaces  representing  the  posterior  articular  pro- 
cesses.’ If  then  these  anterior  caudal  vertebrae  are  characterized  by  the  absence  of 
the  posterior  oblique  processes,  and  as  in  the  succeeding  elements  of  the  series  the 
invariable  tendency  is  to  the  disappearance  of  articular  processes  whether  in  front  or 
beliind,  the  terminal  angular  vertebrae  (Plate  XXX.  figs.  12, 13)  in  which  the  posterior 
oblique  processes  are  still  well-developed,  projecting  from  the  back  part  of  the  base 
of  the  spine,  cannot  belong  to  the  same  species  as  those  just  described,  without 
violating  those  analogies  which  have  hitherto  held  good  ; for  we  cannot  well  admit  the 
reappearance  of  posterior  oblique  processes,  after  they  have  once  subsided,  in  a more 
posterior  part  of  the  same  caudal  series.  Other  discrepancies  equally  marked  forbid 
their  association. 

There  remain  then  to  represent  the  Cetiosaurus  brevis,  in  the  specimens  under 
consideration,  only  the  above  four  caudal  vertebrae,  which  are  truly  so  whale-like  in 
their  form,  as  to  be  pre-eminently  worthy  of  that  generic  appellation.  Probably  they 
are  portions  of  one  or  other  of  the  species  of  that  genus  from  the  Oolites,  indicated 
by  Professor  Owen,  chiefly  from  the  more  posterior  caudal  vertebrae. 

The  close  resemblance  which  these  unique  caudal  vertobrae'f  present  to  two  re- 
markable ones  figured  by  Cuvier:|:  from  the  oolite  of  Honfleur,  was  long  ago  recog- 
nized by  Dr.  Mantell.  They  are  thus  described : ‘ a corps  cylindrique,  presque 
aussi  long  que  large,  marque  de  chaque  cote  d’une  petite  fossette,  a faces  planes, 
circulaires,  a canal  medullaire  fort  etroit,  a partie  annulaire  non  articulee  ; I’apophyse 
epineuse  haute,  et  droite ; les  transverses  au  niveau  du  canal  medullaire,  grosses 
cylindriques,  dilatees  verticalement  au  bout ; et,  ce  qui  est  tres  remarquable,  les 

* Ante,  p.  294. 

t An  outline  of  one  of  these  vertebrae  is  given  in  Dr.  Mantell’s  Memoir,  Philosophical  Transactions,  1841, 
Plate  IX.  6g.  13. 

\ Tome  V.  pi.  22,  figs.  1 and  2.  Oss.  Foss.  ed.  1824. 


THE  IGUANODON  AND  HYL^EOSAURUS. 


297 


articulaires  'posUrieures  petites,  pointnes,  rapproch^es,  et  donnant  dans  deux  petites 
fossettes  entre  les  anterieures  et  aii-devant  de  labasse  de  I’epineuse,’  ‘Elies  doivent 
appartenir  a une  espece  de  Sauriens  tres-voisine  des  Plesiosaurus.’  Ocular  inspec- 
tion can  alone  safely  indicate  the  propriety  of  associating  these  vertebrae  together  as 
belonging  to  the  same  species  or  genus.  Probably  the  mutilated  remains  of  a large 
Saurian,  from  the  lower  greensand  at  Hythe,  may  belong  to  this  genus,  and  also  the 
teeth  of  the  provisional  ^ Polyptychodon  occurring  in  the  same  formation.  The 
Wealden  deposits  intercalated  between  two  marine  formations,  contemporaneous  with 
them  in  a certain  sense,  may  well  contain  a few  vertebrae  of  the  great  Saurians  whicii 
swarmed  along  the  shores  of  the  bays  indenting  the  “ Country  of  the  Iguanodon,” 
or  even  entered  occasionally  the  mouths  of  its  mighty  rivers.  If  these  four  caudal 
vertebrae  are  specifically  different  from  any  found  in  the  more  ancient  oolite,  to  pre- 
vent confusion,  and  to  remove  the  objection  that  may  well  be  raised  against  the 
nomen  trivi ale  ‘brevis' — for  who  will  venture  to  indicate  the  relative  length  of  an 
animal  with  no  known  affine,  from  four  of  its  anterior  caudal  vertebrae  ? — we  propose 
to  name  the  species  to  which  they  belong,  Cetiosaurus  Conyheari,  in  honour  of  the 
Dean  of  Llandaff,  one  of  the  earliest,  ablest,  and  most  distinguished  geologists  and 
palaeontologists  of  England. 

The  massive  sacrum  of  the  Iguanodon  (Plate  XXVI.)  is  composed  of  a series  of  six 
vertebrae  anchylosed  together  in  a nearly  straight  line;  the  neural  arches  unite  at  an 
early  period  above  the  intervertebral  foramina,  and  form  a tunnel  over  the  spinal 
canal,  while  the  short  spinous  processes  coalesce  into  a thick  median  ridge.  The 
bodies  of  the  second,  third,  and  fourth  vertebrae,  are  only  half  as  broad  as  those  of  the 
first  and  two  last,  which  are  of  nearly  equal  width,  but  all  have  the  same  length. 
The  free  articular  surface  («')  of  the  first  sacral  is  flat  or  rather  slightly  convex, 
especially  in  the  vertical  diameter,  and  presents  an  oval  contour ; the  posterioii  facet 
of  the  sixth  (a")  is  subcircular  and  slightly  concave,  but  deepest  above. 

The  body  of  each  is  more  or  less  constricted  in  the  centre,  so  that  their  surfaces 
are  deeply  concave  lengthwise ; this  contraction,  and  the  marked  expansion  towards 
the  articular  facets,  is  most  striking  in  the  smaller  middle  vertebrae,  least  so  in  the 
first;  and  the  more  or  less  rounded  transverse  ridges  at  the  lines  of  anchylosis  give 
the  inferior  surface  of  this  chain  an  undulating  outline.  The  neural  lamina  of  the 
first  sacral  about  its  root  is  much  contracted  in  the  antero-posterior  diameter,  and 
chiefly  from  behind  forwards,  so  as  to  leave  a large  tract  of  the  body  exposed  poste- 
riorly, while  the  anterior  notch  is  comparatively  shallow.  The  neural  laminae  of  the 
four  succeeding  vertebrae  are  displaced  slightly  forwards,  so  that  the  anterior  extre- 
mities of  their  bases  rest  upon  and  excavate  the  postero-superior  angles  of  the  bodv 
in  front,  and  are  also,  perhaps,  partly  wedged  into  the  intervertebral  space  ; each  how-, 
ever  impresses  and  is  mainly  attached  to  its  own  centrum  ; and  that  of  the  last  sacral 
is  restored  almost  to  its  normal  position,  projecting  only  slightly  beyond  the  anterior 
aspect  of  the  body,  leaving  a portion  of  its  upper  surface  uncovered  behind,  to  form 


298 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


the  floor  of  the  large  intervertebral  foramen.  The  preceding  foramina  intervertebralia, 
instead  therefore  of  being  situated  more  or  less  over  the  union  of  two  contiguous 
bodies,  are  thrown  forwards  in  the  same  ratio  as  the  neural  laminae,  encroach  on  the 
centrum  in  front,  and  generally  occur  over  the  junction  of  its  posterior  and  two  an- 
terior thirds.  In  the  first  sacral  the  body  has  a subquadrangular  section ; the  lateral 
aspects  are  impressed  by  a fossa  beneath  the  root  of  the  neuropome,  and  meet  the 
inferior  surface  nearly  at  right  angles,  which  are  rounded  off;  the  lower  aspect  is 
but  slightly  convex  transversely  ; sometimes  it  presents  a median  ridge  separating  two 
very  shallow  concavities,  perforated  by  vascular  foramina.  The  anterior  oblique 
processes  project  considerably  beyond  the  margin  of  the  neural  arch,  and  are  nearly 
horizontal,  and  separated  from  each  other  by  a wide  notch.  The  bodies  of  the  three 
succeeding  vertebrae,  as  already  mentioned,  are  narrow,  constricted  in  the  centre, 
compressed  laterally  in  the  lower  moiety,  and  rounded  transversely  below,  with  a 
more  or  less  distinct  longitudinal  mesial  ridge,  sometimes  replaced  by  a groove  in 
the  third.  In  other  cases  they  appear  to  be  flattened  inferiorly,  without  our  being 
able  to  regard  them  as  distinct,  so  that  there  appears  to  be  a considerable  range  of 
variation  attributable  to  age  and  sex,  &c.  Each  lateral  surface  presents  a small  digital 
fossa  (Plate  XXX.  fig.  16)  towards  the  middle  of  its  height  and  nearer  its  posterior 
extremity,  as  if  the  centrum  had  been  pinched  up  between  the  thumb  and  fore-finger. 
Above  the  fossa  the  centrum  expands,  the  anterior  angle  (Plate  XXX.  fig.  14*)  of  the 
expanded  portion  being,  as  it  were,  removed  and  flattened  out  by  the  base  of  the 
neural  lamina,  and  also,  perhaps  chiefly,  by  the  sacral  rib,  which  is  wedged  deeply 
into  the  intervertebral  space  ; the  posterior  angle  (Plate  XXX.  fig.  14§),  like  that  of 
the  first  sacral,  is  removed,  but  to  a much  less  extent  than  the  anterior ; between  them 
is  the  smooth,  semilunar,  oblique  notch  (Plate  XXX.  figs.  14,  15,  16,  ^),  impressing  the 
slightly  elevated  parapet  which  bounds  externally  the  wide,  deeply  concave  floor  of 
the  spinal  canal.  In  the  two  posterior  sacral  vertebrse  the  bases  of  the  neural  laminae 
begin  to  expand  inwards,  so  as  to  cover  the  upper  surface  of  the  centrum,  in  the 
last  sacral  meeting  in  the  centre  and  leaving  only  a small  triangular  tract  in  front 
and  behind  exposed ; thus  the  calibre  of  the  canal  is  diminished.  The  bodies  of  the  two 
last  vertebrae  expand  to  nearly  the  same  diameter  as  the  first,  but  the  lateral  surfaces 
converge  more  or  less  rapidly  to  an  inferior  mesial  convexity,  varying  in  breadth 
and  prominence.  By  the  relative  size  of  the  two  extremities  of  the  spinal  canal  in 
the  sacrum,  we  are  enabled  most  readily  and  certainly  to  determine  its  position.  The 
bases  of  the  strong  sacral  ribs  (Plate  XXVI.  h,  h,  h,  Plate  XXX.  figs.  15,  16  A)  are 
compressed  in  the  antero-posterior  diameter  and  impacted  in  the  intervertebral 
spaces,  descending  nearly  to  the  inferior  surface  of  the  centre,  and  rising  high  upon 
the  neural  laminae,  which  are  also  excavated  to  give  an  additional  surface  of  attach- 
ment. The  neural  laminae  also  send  out  vertical  processes  {plagiajjophyses)  which  are 
superimposed  upon  the  sacral  ribs,  and  early  coalesce  with  them  to  form  the  thick 
partitions,  which  extend  outwards,  gradually  increasing  in  length  to  the  last ; and 


THE  IGUANODON  AND  HYE^OSAURUS. 


299 


enclose  between  them  the  large  circular  sacral  foramina.  The  inferior  angles  of  the  free 
extremities  of  the  five  posterior  ribs  expand  and  coalesce  to  form  a band  completing  the 
sacral  foramina  without  (Plate  XXVI.  //')•  The  thickest  and  strongest  of  these  septa 
is  the  second,  it  is  also  inclined  sliglitly  backwards  ; the  second  or  third  posterior  ones 
have  a tendency  forwards.  The  corresponding  compressed  rib-like  process  of  the 
first  sacral  is  perhaps  chiefly  formed  by  the  transverse  process,  and  does  not  appear 
to  have  reached  the  band  above-mentioned.  The  vertical  septa  extended  as  high  as 
the  base  of  the  spinal  ridge,  and  appear  to  have  had  a convex  upper  edge  and  a con- 
cave lower  one.  Curious  bony  buttresses  (Plate  XXVI.  3*)of  a triangular  form  seem  to 
have  partly  roofed  over  some  of  the  sacral  foramina  ; these  are  most  probably  remains 
of  a lateral  expansion  of  the  side  of  the  spinal  platform,  at  right  angle  hence  to  the 
vertical  portion  of  the  transverse  process.  These  parts  are,  however,  so  much  muti- 
lated that  we  must  have  more  perfect  specimens  for  examination  ere  many  interest- 
ing points  can  be  fully  elucidated.  The  band  above-mentioned  is  curved  longitu- 
dinally in  its  anterior  two-thirds,  with  a concavity  looking  downwards  and  outwards, 
the  posterior  part  of  the  arc  being  twisted  slightly  from  within  outwards  on  its  axis ; 
the  portion  contributed  by  the  two  posterior  ribs  is  convex  externally,  passing  into 
the  concavity  at  a very  obtuse  angle.  The  bands  of  opposite  sides  are  much  more 
closely  approximated  in  front  than  behind,  but  are  most  remote  opposite  the  angle 
just  mentioned. 

This  instructive  specimen  of  the  sacrum  also  points  out  the  true  position  of  the 
Ilium  (Plate  XXVI.  A),  the  form  of  which  is  well  seen  in  the  two  detached  examples  in 
the  Maidstone  Iguanodon*.  The  slender  anteriorly  prolonged  extremity,  which  is  sup- 
posed in  the  Report  on  British  Reptiles  to  be  the  posterior,  is  only  an  exaggerated 
condition  of  the  short  spine  projecting  forwards  from  the  ilium  in  the  smaller  Lacertee. 
From  the  form  and  position  of  the  head  of  the  femur,  I am  inclined  to  think  that  no 
part  of  the  surface  of  the  acetabulum  is  present  in  this  mutilated  specimen  ; it  is  per- 
haps fractured  (A"")  across  the  neck  or  contracted  portion,  beneath  which  it  would 
expand  to  contribute  to  the  formation  of  the  acetabular  fossa. 

The  beautiful  and  interesting  fragment  of  the  sacrum  of  a Dinosaur,  consisting  of  the 
four  posterior  vertebral  bodies  anchylosed  together,  Plate  XXVII.  figs.  2,  3,  presents 
certain  differences  in  the  form  of  the  centrum,  which  are  perhaps  due  to  age  and  sex  ; 
but  I am  inclined  with  Dr.  Mantell  to  regard  it  as  probably  belonging  to  the 
Hylseosaurus,  which  must  have  presented  a nearly  similar  structure  of  the  pelvis. 
The  sacral  fragment  referred  to  the  Hyleeosaurus  by  Professor  Owen,  cannot  at 
present  be  found  to  institute  the  necessary  coiiiparison  with  the  present  specimen. 
The  age  and  size  of  the  individual  appear  to  have  had  no  very  obvious  relation  to  the 
occurrence  of  anchylosis  in  the  sacral  column,  cis  we  meet  with  examples  of  very 
dissimilar  size  both  anchylosed  and  separate.  There  is  the  same  disproportion  be- 
tween the  central  and  extreme  elements  of  this  chain  as  we  have  seen  in  the  sacrum 
* Philosophical  Transactions,  1848,  Plate  VIII.  fig.  28. 


300 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


of  the  Iguanodon,  but  the  bodies  are  relatively  broader  and  flatter,  and  not  so  much 
pinched  up  beneath  the  intervertebral  notches ; but  a reference  to  the  Plate  will  furnish 
a better  idea  of  these  differences  than  can  be  conveyed  in  words. 

Since  the  observations  on  which  the  above  remarks  are  chiefly  founded  were 
made,  Dr.  Mantell  has  informed  me,  that  according  to  the  account  given  by  the 
fisherman  who  collected  the  cervical,  anterior  and  middle  dorsal,  first  sacral,  and 
anterior  caudal  vertebrae — all  of  which  I had  assigned  to  the  Iguanodon — they  were 
found  not  only  in  the  same  limited  area,  but  in  such  collocation  as  to  give  rise  to  the 
conviction  in  the  mind  of  one  who  had  certainly  no  theory  to  support,  that  they  con- 
stituted portions  of  the  same  ‘ backbone,’  and  were  associated  with  bones  of  the 
hinder  extremity  of  the  Iguanodon  of  proportionate  size,  now  in  Dr.  Mantell’s  Col- 
lection, and  partly  described  in  this  memoir.  Although  unwilling  to  lay  any  undue 
stress  on  this  circumstance,  it  will,  we  conceive,  raise  in  the  minds  of  future  ob- 
servers such  presumptive  evidence  in  favour  of  the  opinions  here  advanced,  as  may, 
independently  of  the  mere  intrinsic  value  of  the  argument  from  analogy,  lead  them  to 
view  favourably  our  proposed  restoration  of  thewertebral  column  of  the  Iguanodon. 

The  time  is  perhaps  not  far  distant,  when  the  exertions  of  the  many  collectors  of 
the  Wealden  fossils  will  yield  the  materials  for  continuing  these  interesting  researches, 
and  modifying  or  confirming  our  conclusions.  And,  although,  we  feel  it  is  difl&cult 
to  convey  to  the  minds  of  others  that  conviction  of  their  accordance  with  nature, 
which  has  been  impressed  on  our  own  after  the  repeated  examination  of  a more  ex- 
tensive and  instructive  series  of  specimens  than  has,  perhaps,  fallen  under  the  observa- 
tion of  any  other  palaeontologists,  we  may  be  permitted  meanwhile  to  indulge  the 
hope  that  a step  has  been  taken  in  the  right  direction,  to  reconstruct  the  skeleton  of 
the  marvellous  Reptilian  Herbivore,  whose  earliest  known  remains  were  first  exhumed 
from  the  Wealden  formation  of  Sussex,  during  the  infancy  of  Palaeontology. 

Description  of  the  Plates. 

PLATE  XXVI. 

Sacrum  of  the  Iguanodon;  in  the  Collection  ofW.  D.  Saull,  Esg.,  F.G.S. 

(One-half  linear,  the  natural  size.) 

Figs.  1, 2,  3,  4,  5,  6.  The  six  anchylosed  vertebrae  composing  the  Sacrum  ; 1,  is  the 
first  or  most  anterior  vertebra. 
a'.  Anterior  articulating  facet. 

a”.  Posterior . 

h.  Sacral  ribs. 

h'.  Confluence  of  the  sacral  ribs  at  the  outer  extremity  of  the  left  side. 
h".  Sacral  foramina. 

* Expansion  of  bone  from  the  rib  across  a sacral  foramen. 


/%?/  Tranj-.  WICUDALK  m\ 


Sacrum  of  the  I^uanadou. 

ff  errear  the  nnturat  Ji-xe.) 


TPiet,  >fel. 


Printed  by  J.Basire. 


JDirJud,  m . 


/////,  Tnm.s.  MDCOOXLIX./’^r/^' 


Di/iA.i  i (t  fl'eji,  del. 


Part  of  the  PacriLm  of  the  Jlytoeosaunes-?  nai.sue. 

Frmeed 


J.  Din  del.  lUO. 


yy///,  /h^MrMDCCCXLlX  XXyiJT.^.3^^ 


/ '/'f/i/(\.'  u,'iJ  A'/f,)Vrt . 


J.  de/.  ei  cfi/i. 


THE  IGUANODON  AND  HYLiEOSAURUS. 


301 


A.  The  right  ilium. 

A'.  Anterior  prolongation  of  the  same. 

A".  Posterior  extremity  of  the  ilium,  of  which  several  inches  are  wanting. 
A'".  Crest  or  upper  margin  of  the  same. 

A"".  Remains  of  the  neck  of  the  ilium. 

PLATE  XXVII. 

This  fossil  consists  of  the  four  distal  anchylosed  vertebrae  of  a sacrum  belonging 
either  to  the  Hylaeosaurus  or  Iguanodon  {natural  size).  Collected  by 
Captain  Lambart  Brickenden,  F.G.S. 

Fig.  2.  The  inferior  or  visceral  aspect. 

Fig.  3.  The  side  or  lateral  aspect. 

3,  4.  The  two  middle  slender  vertebrae. 

5,  6.  The  tv/o  larger  and  posterior  vertebrae. 
h.  Sacral  ribs. 

j.  The  spinal  canal. 

k.  Line  of  intervertebral  anchylosis. 

b.  Bases  of  the  neural  laminae. 

PLATE  XXVIII. 

V ertebroe  of  the  Iguanodon. 

Fig.  4.  Cervical  vertebra  from  Brook  Bay : this  specimen  is  somewhat  compressed 
vertically,  so  as  to  appear  wider  and  more  elliptical  transversely  than 
natural. 

V.  Inferior  view. 

4*.  Upper  view. 

4^  Lateral  view. 

The  several  parts  in  this  and  the  other  vertebrae  are  indicated  by  the  following 
signs : — 

a.  The  body  or  centrum. 

d.  The  anterior  articulating  surface  of  the  same. 

a".  The  posterior  — . 

h.  The  neural  arch. 

c.  The  spinous  process. 

d.  Superior  transverse  process. 

e.  Inferior  transverse  process. 

f.  Anterior  oblique  process. 

g.  Posterior  oblique  process. 

h.  Rib  or  costal  process. 

MDCCCXLIX.  2 R 


302 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


i.  Chevron  bone. 
j.  Spinal  canal. 

h.  Line  of  intervertebral  anchylosis. 

1.  Articulating  surface  for  the  head  of  the  rib. 

Fig.  5.  Anterior  dorsal  vertebra  from  the  Isle  of  Wight. 

6“.  Anterior  view. 

5*.  Posterior  aspect. 

5''.  Lateral  view. 

Fig.  6.  Cervical  vertebra,  in  Mr.  Saull’s  Collection,  lateral  view ; the  anterior  con- 
vexity has  been  chiseled  away. 

Fig.  7-  Middle  dorsal  vertebra,  in  British  Museum. 

7“.  Lateral  view. 

7**  Anterior  view. 

PLATE  XXIX. 

Dorsal  Vertehrae  of  the  Iguanodon. 

(one-fourth  linear,  natural  size.) 

Fig.  8.  Middle  dorsal  vertebra.  Isle  of  Wight ; found  with  fig.  4,  Plate  III. 

8“.  Posterior  aspect. 

8*.  Anterior  aspect. 

S'".  Lateral  view. 

Fig.  9.  Posterior  dorsal  vertebra  found  with  the  above. 

Cervical  Vertehrae  of  a very  young  Iguanodon. 

(natural  size.) 

Fig.  9*.  A series  of  three  convexo-concave  vertebrae  from  the  Wealden  of  the  Isle  of 
Wight. 

9“*.  The  upper  or  dorsal  aspect,  showing  the  spinous  and  oblique  processes 
of  the  neural  arches  ; the  vertebrae  are  somewhat  displaced,  and  in- 
jured by  compression. 

9**.  Lateral  view  of  the  same. 

9^^*.  Lateral  view  of  one  of  the  vertebrae  detached. 

This  interesting  series  of  cervicals  (for  the  loan  of  which  I am  indebted  to  J.  S. 
Bowerbank,  Esq.)  was  associated  with  other  portions  of  the  skeleton  of  a very  young 
individual,  consisting  of  a connected  suite  of  fourteen  dorsal  vertebrae  of  the  usual 
type,  several  ribs  with  portions  of  the  dermal  integument,  metatarsal,  phalangeal, 
and  ungueal  bones,  and  several  others  which  are  at  present  too  much  concealed  by 
the  investing  sandstone  to  admit  of  their  identification. 

These  vertebrae  are  especially  instructive,  because  they  establish  the  true  charac- 
ters of  the  cervical  region  of  the  spine  of  the  Iguanodon  in  a very  young  state. 


PhaTmrom)C<^mM..Pla^  Vk\\.p.30Z. 


Tertebroe  of  the  Ig  nano  don. 


.•'/// /ir , k' SCiHil'r  (U’l. 


pruUed  Pj  PPiis/7Y>. 


.0  Dot /ref.  /j/A 


M/V.  7ran.y.  MnCOiKIJX.  Va.p.:VJ,3. 


n^ffil/h,('Of‘<XCO//i  mid,  I e7'h’/j7‘^  of  the  iTJUfftiPTiT}/^. 


C.  Sr/if//‘f  <//»/, 


J-'rU!  fe(0  ii/  J £a.f/>-e 


-■f-PinAe/  £t/t. 


THE  IGUANODON  AND  HYL^OSAURUS. 


,303 


Unfortunately  the  bodies  of  the  vertebrae  have  been  crushed  and  compressed  almost 
flat  laterally,  and  the  natural  form  of  the  inferior  part  of  the  centrum  is  destroyed, 
the  visceral  aspect  presenting  a sharp  ridge,  and  thus  assuming  a different  contour 
to  that  of  the  adult  cervical  figured  in  Plate  XXVIII.  fig.  1,  which  has  been  compressed 
in  an  opposite  direction.  Nevertheless,  the  close  analogy  between  these  vertebrae  is 
sufficiently  obvious  ; the  structure  of  the  neural  arch  (as  seen  in  fig.  9“*)  is  identical ; 
and  the  only  essential  difference  in  the  bodies  of  the  respective  vertebrae,  is  that  the 
anterior  articulating  facet  (a')  is  much  less  prominent  in  the  young  specimen  than  in 
the  adult : but  as  the  posterior  facet  {a")  is  deeply  concave,  it  is  probable  that  in 
the  recent  state  the  anterior  facet  possessed  a cartilaginous  convex  epiphysis,  by  which 
the  ball-and-socket  joint  was  completed:  as  in  the  skeleton  of  the  young  Gavial  the 
facets  of  the  sacro-coccygeal  vertebra  are  flat,  though  very  convex  in  the  adult*^; 
so  in  the  Iguanodon,  the  ball  and  socket  of  the  cervicals  may  not  have  been  fully 
developed  and  ossified  till  the  reptile  arrived  at  maturity. 

Fig.  A.  A concavo-convex  dorsal  vertebra  from  Tilgate  Forest : natural  size. 

I have  introduced  this  figure  to  prove  the  existence  in  the  Country  of 
the  Iguanodon,  of  small  Lizards  having  the  spinal  column  constructed  of 
vertebrae  anteriorly  concave,  and  posteriorly  convex,  as  in  the  living 
Iguanas,  Crocodiles,  &c. : the  very  reverse  of  those  above  referred  to  the 
Iguanodon. 

A,  is  a lateral  view  ; and  A'  the  anterior  aspect,  showing  the  deep  socket  for  the 
reception  of  the  head  of  the  antecedent  vertebra. 

PLATE  XXX. 

Fig.  10.  The  right  Scapula  or  Omoplate  of  the  Iguanodon:  from  Tilgate  Forest 
(one- fourth  natural  size). 

10“.  Inner  aspect. 

10*.  The  external  aspect. 

a.  The  upper  or  spinal  end. 
h.  The  humeral  extremity. 

c.  The  coracoid  facet  or  articulating  surface. 

d.  The  glenoid  facet,  forming  half  the  cavity  for  the  reception  of  the 

head  of  the  humerus. 

Fig.  11.  The  right  Coracoid  of  the  Iguanodon;  drawn  of  a size  to  correspond  with 
the  scapula. 

s.  Scapular  facet  or  surface  to  articulate  with  the  scapula. 
d'.  Glenoid  facet,  forming  with  the  corresponding  part  of  the  scapula,  the 
glenoid  socket. 

e.  Notch  for  the  passage  of  vessels. 

* See  Wonders  of  Geology,  6th  edit.  p.  418. 

2 R 2 


304 


DR.  MANTELL  ON  THE  OSTEOLOGY  OF 


Fig.  12.  Posterior  caudal  vertebra  of  the  Iguanodon. 

12“.  Anterior  aspect. 

12*.  Lateral  view. 

Fig.  13.  Distal  caudal  vertebrae  of  the  same;  one-half  natural  size.  This  specimen 
and  the  preceding  are  from  Tilgate  Forest. 

Fig.  14.  A middle  sacral  vertebra  of  the  Iguanodon  from  Brook  Bay;  one-half  na- 
tural size.  In  the  collection  of  J.  Baber,  Esq.,  of  Knightsbridge. 

14“.  Lateral  view. 

14*.  Upper  or  spinal  aspect. 

Figs.  15,  16,  17.  Represent  portions  of  a chain  of  sacral  and  caudal  vertebrae  of  the 
same  Iguanodon : from  Charlwood  in  Surrey.  In  the  cabinet  of 
P.  Martin,  Jun.,  Esq.,  of  Reigate. 

Fig.  15.  The  two  anterior  sacrals;  foramen  for  the  transit  of  the  sacral  nerves. 
Fig.  16.  An  entire  middle  sacral,  with  portions  of  the  adjoining  vertebrae  anchylosed 
at  each  end. 

Fig.  17.  Four  consecutive  anterior  caudals  with  remains  of  the  chevron  bones  (*). 

PLATE  XXXI. 

Humeri  or  Arm-bones  of  the  Iguanodon. 

Fig.  18.  Inferior  portion  of  the  right  Humerus  of  a young  Iguanodon;  one-third 
natural  size. 

18“.  Front  or  anterior  view. 

18*.  Lateral  view. 

1 8^  Posterior  view. 

18*^.  The  condyloid  articulating  surface  seen  from  below. 

Fig.  19.  Right  Humerus,  one-twelfth  natural  size:  from  the  Isle  of  Wight;  in  the 
possession  of  Mr.  Fowlstone  of  Ryde. 

19®.  Posterior  view. 

19*.  Front  or  anterior  aspect. 

19®.  Articulating  surface  of  the  proximal  extremity  of  the  bone  seen  from 
above. 

1 9*^.  Distal  or  condyloid  articulating  surface  seen  from  below. 

Fig.  20.  Right  Humerus  of  the  Iguanodon,  from  the  Maidstone  specimen  in  the 
British  Museum  ; one-sixth  natural  size : the  posterior  aspect  only  is 
exposed. 

Fig.  21.  Upper  extremity  of  the  Humerus  of  a very  young  Iguanodon  : from  Tilgate 
Forest ; one-third  natural  size. 

21®.  Posterior  aspect. 

21*.  Anterior  view. 

21®.  Articulating  surface  of  the  proximal  extremity  seen  from  above. 


P}a/.  T’rajcsMPXmAPPlaPe 


TTxaP.sixe. 


i r/x//-sixe. 


ena-t.  six,e. 


iz  71X11.6. six/ije. 


inzxP.STYe 


c 


Huxnerc  o6‘  6/xe  J fjxfxxxfor/o?/. . 


Q -Sc?! Off,  (6e6. 


Puited  by  ,7.  Ba.i'irp. . 


.7  D/7t6>/,  /?/// . 


I 


Trml'£dj  hyJ.ljainre. 


Posten^^r  party  ot  thr  / 
/ uatr\ 

t .h  ClirvTrnihoTLes . 


'F/(j7.  7hf//.>’.]VIJ)CCCX]  X7TlcUe'f:!3SLp.305- 


22^ 


\l  of  f//e  /fr/l/Tosay7jr//s. 

U'.J 


’rjp  prccej^ej  cL . dermal  l?(rmj. 


■ / Z)7f/7'f'7,  f7r‘2.  eO  7/07/ . 


1 


/ 


/ 

/, 


* 


THE  IGUANODON  AND  HYL.EOSAURUS. 


305 


The  principal  points  in  the  above  specimens  are  indicated  by  the  follow- 
ing letters. 
a.  The  head. 
h.  Inner  tuberosity. 

c.  Outer  tuberosity. 

d.  Deltoid  crest,  or  ridge  for  the  insertion  of  the  deltoid  muscle. 

e.  Inner  condyle. 

f.  Outer  condyle. 

g.  Olecranal  furrow  or  depression. 

PLATE  XXXII. 

ertehrce  and  Dermal  Bones  of  the  Hylceosaurus. 

Fig.  22.  Posterior  portion  of  the  spinal  column  of  the  Hylaeosaurus,  from  the  Weald 
of  Sussex  ; one-sixth  natural  size. 

The  series  of  nine  verteorce  anterior  to  the  three  terminal  ones  in  this 
specimen,  lies  imbedded  on  the  stone  in  a position  the  reverse  of  that 
of  the  other  portions  of  the  spinal  column ; the  haemal  aspect  of  the 
bodies  of  the  vertebrae,  with  the  corresponding  chevron  bones  (/,  i,  i), 
being  uppermost. 

22“.  Outline  of  the  form  and  arrangement  of  the  chevron  bones  in  the  distal 
part  of  the  column. 

22*,  22"",  22*^.  Illustrate  the  modifications  of  form  in  the  chevron  bones  in 
the  anterior  part  of  the  specimen. 

22^  Distal  chevron  bone. 

22^.  Middle . 

22^.  Anterior . 

Fig.  23.  Dermal  bone  from  the  middle  portion  of  fig.  22  ; one-half  natural  size. 

Fig.  24.  Dermal  tubercle  or  horn  of  the  Iguanodon ; natural  size ; from  Ridgway, 
near  Weymouth. 


I \ ,1 


t ' 


/•'■■ , 


CM 


' ' ' ' tv 


'■;[)  ‘riK  i;  !iv<r'^^u'1(;'<il^l:^■  .^W  *‘ 


„ IT;  / •!t.: 

'M 

■;  --\  '■'';■'■  ; ■■  ’.'  ' ,. 


. 7, 'i ■,r»  (,'.-th)i  .'.!;/ i.  ■>  . '>  y^  t.  - ^s^ 

;£  -Vi ’ft  v^t‘T;ul  {]jttj((i-j*>“fjO  .;:  . ,' 


in 

'j 


I 


t,:  ■>■ 


M;.  'n  itifiit 


iii  -yiiu; 

,l>  ,V,V<, ■ ' i'';)7  'nU' 


'sd 

mm 


■••  ‘ ' '■?  i‘  ■ r,>'n  <■}  ‘}th  '■:1.>  I-,,  .r^-.  t;<J 


■■''■/iC! 


'l^  * I ’ ' 


7vk'-<  IptrM-,;:  j|,',:  -fM 

''i’'!  v.  .t  - -.x?-;  ^:;^|^r^;u^^^«>fwy'^iii,il^^p■  ryit)  h>'V^ 


'•■  f'v'  i- 

• '■  ■ ' , ■/  .«'■■  K'ld'  ''"' 


, ; yj  •'.  '\  ,•  ' ;.: '•TV-i'Jfv'i 4-' v/,>  '.•'■■<.  >•;*.;■'■■  -.y  ryi-^ 

v''^i v"": '■ 


'■  ' 


7^'  '44. ■'<■;.■  ,<  ..  ■ ' .,," 

*■  '^5’i  ■’  1-  i-’’' 

" ■ i‘\.yi  .4  ,. '7  .t'l"'.  r-'y 


.^■■.VVvv:’:- 


),  ‘ ■ ^vri^  ' 1).  '■<•'•' 


■ • ,,  ,..  ;:V' 
> . ,.  •’■■.'..>•  -v-ry, 

4.7  .[■'■'^"A'M.-  i^'>'‘^ 
.,  • \ ; ...'.ii''  i/j'/J 


;> 

,':  - , .i"  yimpf-M 


[ 307  ] 


XVI.  On  the  Reduction  of  the  Thermometrical  Observations  made  at  the  Apartments  of 
the  Royal  Society , from  the  years  1774  to  1781,  and  from  the  years  1787  to  1843. 
By  James  Glaisher,  Esq.,  F.R.S.,  of  the  Royal  Observatory,  Greenwich. 
Communicated  by  John  Lee,  Esq.,  LL.D.,  F.R.S.  8fc. 

Received  February  21, — Read  May  3,  1849. 


The  meteorological  observations  which  have  been  made  at  the  Apartments  of  this 
Society,  extend  over  so  long  a period  of  time,  that  if  the  instruments  used  have  been 
good,  and  the  observations  have  been  faithfully  recorded,  the  results  which  can  be 
deduced  from  them  must  be  of  great  value;  on  the  other  hand,  if  either  of  these 
essentials  has  been  neglected,  any  results  from  them  would  be  valueless. 

To  the  present  time,  so  much  uncertainty  seems  to  have  rested  upon  these  observa- 
tions, and  so  much  suspicion  upon  their  accuracy,  that  they  have  been  little  used, 
and  generally  when  reference  has  been  made  to  them,  it  has  been  accompanied  with 
the  remark  that  the  results  were  not  satisfactory,  and  till  recently  such  was  the 
opinion  which  I entertained  myself. 

In  the  year  1848  I had  the  honour  of  presenting  to  this  Society  the  determination 
of  the  diurnal  variations  of  the  different  meteorological  elements,  and  the  corrections 
to  be  applied  to  monthly  mean  values  of  observations  taken  at  any  time  of  the  day, 
to  deduce  from  them  the  true  values  for  the  month. 

The  accordance  which  I had  found  in  the  diurnal  variations  year  by  year,  led  me  to 
suspect  that  the  corrections  would  apply  to  a great  number  of  years.  To  determine 
this  I had  recourse  to  the  observations  of  this  Society.  Throughout  this  series  two 
thermometers  have  been  used  in  the  ordinary  daily  observations  ; each  was  placed 
2 or  3 inches  from  a wall,  one  faeing  E.N.E.  and  tlie  other  W.S.W.  As  the  sun 
shines  on  the  eastern  part  of  the  building  in  the  morning,  the  thermometer  to  the 
westward  was  made  use  of  for  the  morning  observation  during  that  season  of  the 
year  when  the  sun  rose  high  enough  to  affect  the  other : for  all  other  observations, 
that  to  the  eastward  was  employed.  Of  these  instruments  two  observations  have 
been  taken  daily,  the  one  before  and  the  other  after  noon ; the  actual  times,  how- 
ever, have  been  different  at  different  epochs,  and  at  times  different  in  the  same  month  ; 
these  circumstances  were  favourable  for  my  purpose,  though  undoubtedly  they  have 
been  highly  prejudicial  to  the  character  of  the  journal  in  consequence  of  the  diurnal 
variations  being  then  unknown,  and  the  mean  monthly  values  as  printed  differing 
from  the  true  values  for  the  month  by  different  quantities. 

At  every  variation  of  the  times  of  observation,  and  at  different  epochs  with  the 


308 


MR.  GLAISHER  ON  THE  THERMOMETRICAL  OBSERVATIONS 


same  times,  I determined  two  mean  values,  the  one  from  the  morning  observations,, 
and  the  other  from  the  afternoon  observations,  and  compared  the  difference  between 
them,  with  the  difference  as  exhibited  in  my  tables ; in  nearly  all  cases  the  values 
thus  found  were  nearly  alike ; hence  it  appeared  that  the  corrections  apply  equally 
well  to  all  the  years  since  1774. 

Having  ascertained  this  fact,  I felt  I had  the  means,  to  a certain  extent,  of  deter- 
mining the  quality  of  the  instruments  which  have  been  used,  as,  for  the  most  part, 
different  instruments  were  used  in  the  morning  and  in  the  afternoon  observations, 
and  also  the  correctness  of  the  observations  generally ; and  thus  the  means  of  ascer- 
taining the  value  of  the  results  which  could  be  deduced  from  them. 

I need  not  mention  all  the  tests  to  which  I have  subjected  the  observations,  but 
briefly  state  that  the  results  were,  a conviction  on  my  mind  that  the  instruments  had 
been  uniformly  good,  that  the  observations  had  been  faithfully  recorded  as  read  from 
the  instruments,  and  that  very  great  care  had  been  taken  in  reading  at  the  times 
stated ; the  latter  circumstance  was  most  satisfactorily  proved  from  the  fact  of  the 
results  being  the  same  when  the  times  of  observation  have  been  such  that  the  changes 
were  rapid,  and  consequently  a small  error  in  the  time  of  reading  would  have  entailed 
a considerable  error  in  the  results. 

I found  however  that  during  the  time  the  maximum  and  minimum  thermometers 
were  in  use,  their  readings  were  frequently  in  defect  or  excess  respectively  as  com- 
pared with  those  of  the  other  thermometers  made  during  the  day,  and  this  was  found 
to  be  more  frequently  the  case  in  the  later  than  in  the  earlier  observations.  On  ex- 
amining farther  and  bearing  in  mind  that  a self-registering  thermometer,  whose  read- 
ing is  taken  once  a day  only,  merely  registers  the  extreme  reading  which  has  taken 
place  in  the  preceding  twenty-four  hours,  many  of  the  apparent  discrepancies  vanished, 
yet  still  some  remain  for  which  I cannot  account.  I know  it  has  been  said  that  at 
times  the  sun  has  shone  upon,  or  its  reflected  rays  have  impinged  upon  the  maximum 
thermometer ; but,  if  this  has  been  the  case,  I feel  certain  that  it  was  of  rare  occur- 
rence, and  therefore  it  is  not  sufficient  alone  to  warrant  us  in  rejecting  a long  series 
of  observations : possibly  no  journal  of  the  weather  has  been  kept  for  any  length  of 
time,  where  an  attempt  has  been  made  to  have  the  instruments  properly  exposed, 
that  such  accidents  have  not  happened. 

There  being  thus  three  independent  methods  of  determining  the  mean  temperature 
of  the  air,  viz.  first,  from  the  morning  observations  by  one  thermometer;  secondly,  from 
the  afternoon  observations  by  another  thermometer ; and  thirdly,  from  the  observa- 
tions made  by  the  maximum  and  minimum  thermometers,  I had  every  means  of  ascer- 
taining whether  the  one  or  the  other  of  these  methods  was  bad.  Having  satisfied  myself 
that  the  observations  were  well  worth  any  amount  of  labour  bestowed  upon  them,  I 
became  anxious  to  reduce  them  to  a useful  and  accessible  form ; but  the  amount  of 
work  required  to  reduce  observations  extending  from  the  year  1774  to  1843,  with  the 
exception  of  five  years,  from  1781  to  1786,  during  which  interval  no  observations 


MADE  AT  THE  APARTMENTS  OF  THE  ROYAL  SOCIETY. 


309 


were  made,  was  so  great,  that,  unassisted,  I hesitated  to  begin  the  reductions,  although 
the  results,  as  printed  in  the  Philosophical  Transactions,  are  unfit  for  application  to 
useful  purposes,  there  having  been  a departure  in  the  observations  themselves,  from 
an  absolutely  necessary  condition,  viz.  that  of  taking  the  observations  at  stated  times, 
when  the  diurnal  variations  were  unknown. 

About  two  months  after  this,  William  Farr,  Esq.,  who  is  at  the  head  of  the  Statistical 
Department  in  the  office  of  the  Registrar-General,  wished  me  to  supply  the  meteoro- 
logical particulars  of  as  many  years  as  could  be  given  with  certainty,  to  accompany 
statistical  tables  upon  which  he  is  engaged.  Finding  therefore  that  the  demand  for 
the  results  from  trustworthy  observations,  extending  backwards  many  years,  was  in- 
creasing, with  the  knowledge  that  such  could  be  deduced  from  the  observations  of 
this  Society,  together  with  the  hope  of  connecting  the  Greenwich  series  of  observa- 
tions with  these,  I readily  undertook  to  perform  the  work. 

I have  now  the  honour  of  presenting  to  the  Society  the  results  from  all  the  Ther- 
mometrical  Observations  which  have  been  taken  at  Somerset  ITouse.  I have  chosen 
these  in  preference  to  the  Barometrical,  as  being  at  present  more  important,  and  more 
immediately  useful.  The  prevalence  of  epidemic  complaints  renders  it  desirable  to 
compare  the  simultaneous  meteorological  conditions  with  those,  when  no  particular 
disease  prevailed.  The  cholera  epidemic  now  prevalent  has  caused  me  to  prepare 
this  paper  as  quickly  as  possible. 

I shall  now  proceed  to  explain  the  manner  in  which  the  annexed  Tables  were 
formed. 

Table  I.  was  made  by  applying  the  corrections  to  the  mean  of  the  observations 
made  during  every  month,  according  to  the  times  of  the  day  at  which  they  had  been 
taken,  and  thus  determining,  from  the  observations  taken  during  the  day,  one  mean 
temperature  for  the  month,  which  has  been  used  as  the  true  mean  at  all  times  when 
the  self-registering  thermometers  have  not  been  used  ; at  times  when  they  were  in 
use  a second  mean  has  been  found  by  applying  the  corrections  as  mentioned  in  my 
paper  in  the  Philosophical  Transactions  in  1848.  Thus  two  values  of  the  same  ele- 
ment have  for  the  most  part  been  found  monthly ; the  difference  between  these  re- 
sults in  most  cases  was  a quantity  less  than  a degree.  As  both  determinations  rested 
upon  two  observed  readings  daily,  I considered  them  entitled  to  equal  weight,  and  in 
most  cases  I have  taken  a simple  arithmetical  mean  betvveen  them,  which  I have 
adopted  as  the  true  mean  for  the  month.  From  the  accordance  thus  found  by  these 
two  methods,  I inferred  that  either  could  be  used  with  safety  at  times  when  both  sets 
of  instruments  were  not  in  use. 


2 s 


MDCCCXLIX. 


310 


MR.  GLAISHER  ON  THE  THERMOMETRICAL  OBSERVATIONS 


Table  I. — Showing  the  mean  temperature  of  each  month,  as  deduced  from  the  cor-r 
rected  mean  of  the  two  observations  of  the  thermometer  daily,  and  the  corrected 
mean  as  found  from  the  maximum  and  minimum  self- registering  thermometers, 
made  at  Somerset  House  during  the  years  1774  to  1781,  and  from  1787  to  1843. 


Year. 

January. 

February. 

March. 

April. 

May. 

June. 

July. 

August. 

September. 

October. 

November. 

December. 

o 

o 

o 

o 

0 

o 

o 

1774. 

33-1 

39-4 

43-9 

47-9 

52-2 

610 

62-8 

61-5 

55-8 

501 

40-5 

38-5 

1775. 

42-0 

43-3 

42-8 

50-8 

55-2 

63-5 

640 

62- 1 

59-5 

49-5 

41-5 

40-7 

1776. 

28-6 

41 -4 

44-8 

48-3 

51-7 

59-6 

63-8 

62-0 

55-6 

52-8 

44-0 

41-5 

1777. 

35-5 

37-2 

45-7 

45-1 

53-4 

572 

61-5 

63-7 

59-2 

52-6 

45-0 

37-2 

1778. 

36-4 

370 

41-2 

48-0 

55 '9 

62-2 

68-0 

64-8 

54-5 

47-3 

460 

44-2 

1779. 

36-4 

46-7 

48-1 

51-8 

55-8 

58-9 

65-9 

65-2 

61-8 

53-2 

43-2 

41-6 

1780. 

30-2 

36-7 

50-3 

44-7 

57-2 

600 

64-2 

670 

60-4 

513 

40-8 

38-0 

1781. 

37-8 

41-7 

43-7 

47-2 

54-2 

63-4 

66-3 

64-3 

1787. 

38-3 

40-9 

43-9 

45-5 

52-4 

58-7 

62-4 

62-4 

55-5 

49-9 

40-9 

41-0 

1788. 

39-0 

401 

39-7 

50-6 

57-4 

59-5 

61-6 

61-2 

570 

50-4 

41-9 

304 

1789. 

35  0 

41-3 

35-5 

45-2 

54-3 

55-7 

59-8 

61-5 

55-7 

48- 1 

40-0 

430 

1790. 

40-2 

42-6 

44-3 

420 

53-7 

57-7 

60-1 

61-2 

550 

50-8 

43-3 

40-4 

1791. 

41-4 

402 

43-2 

49-9 

50-5 

58-5 

60-5 

62-7 

57-9 

47-9 

42-6 

36-2 

1792. 

36-5 

38-8 

43-2 

50-0 

50-7 

55-3 

59-6 

63-5 

56-5 

500 

44-5 

41-4 

1793. 

36-9 

411 

40-4 

43-5 

51-8 

56-3 

65-9 

60-3 

53-9 

53-2 

44-2 

42-4 

1794. 

34-9 

461 

45-4 

50-7 

51-7 

58-5 

66-3 

60-7 

54-8 

49-6 

44-6 

38-2 

1795. 

25‘5 

35-5 

39-7 

46-2 

530 

5'f-6 

59-9 

62- 1 

61-9 

54-7 

42-0 

46-2 

1796. 

46-9 

41-0 

40-1 

49-4 

51-2 

57-0 

59-6 

61-2 

60-2 

47-8 

41-6 

31-8 

1797. 

370 

370 

390 

45-8 

52-4 

55-7 

64-3 

60-3 

55-7 

48-3 

42-7 

42-6 

1798. 

39-4 

39-3 

41-8 

50-3 

54-7 

62- 1 

62-2 

62'8 

57-6 

511 

41-3 

351 

1799. 

34-9 

37-8 

38-3 

42'6 

506 

56-5 

60-8 

58-8 

55-4 

48-6 

44-2 

34-2 

1800. 

38-5 

35-5 

38-6 

49-5 

551 

560 

64-2 

65  0 

59-0 

49-2 

43-5 

39-6 

1801. 

411 

39-9 

45-2 

46-5 

54-7 

59-3 

61-5 

63-8 

59-8 

52-2 

41-5 

37-5 

1802. 

34-5 

40-3 

42-3 

49-6 

51-3 

58-5 

57-5 

66’ 1 

58-1 

45-8 

41-8 

392 

1803. 

35  0 

37-7 

43-4 

48-9 

51-2 

571 

64-7 

630 

53-5 

502 

43-2 

44-7 

1804. 

44-8 

38-3 

42-2 

44-8 

57-7 

62-2 

61-2 

61  2 

605 

52  7 

45-4 

370 

1805. 

36- 1 

40-1 

43-1 

464 

50-7 

55-4 

60-1 

630 

60-4 

48-7 

41-2 

40-9 

1806. 

42-2 

42-9 

41-8 

44-1 

56-1 

60-7 

62-2 

62-7 

58-1 

52-5 

48-7 

48-2 

1807. 

38-3 

41-4 

38-1 

46-5 

56'1 

58-6 

64-5 

65-0 

54-2 

54-3 

40-0 

38-0 

1808. 

38-6 

37-7 

38-2 

436 

58-2 

58-9 

66-7 

63-8 

56-4 

47-4 

45-2 

37-4 

1809. 

320 

45-5 

43-7 

42-2 

56-8 

58-4 

60'6 

60-2 

57-2 

50-9 

40-8 

42-4 

1810. 

360 

400 

43-3 

47-5 

50-8 

59-4 

61-9 

61-8 

60-5 

531 

441 

400 

1811. 

34-3 

41-3 

440 

490 

564 

58-0 

61-0 

58-9 

58-3 

56-3 

46-3 

39-8 

1812. 

37'5 

430 

39  5 

42  6 

52-3 

54-9 

58-4 

58'3 

57-0 

501 

41-9 

36-5 

1813. 

360 

43-0 

44-2 

44-9 

53-4 

56-2 

59-9 

59-6 

55-6 

48-6 

415 

38-0 

1814. 

28-5 

35-4 

36-2 

49-2 

49-7 

54-3 

62- 1 

59-9 

560 

48-6 

42-0 

42-5 

1815. 

33-5 

42-6 

46- 1 

47-7 

55-8 

58-9 

60-9 

61-7 

63-4 

52-7 

40-2 

38-4 

1816. 

38-3 

38-0 

40-3 

44-5 

49-9 

540 

55-5 

59-2 

60-0 

52- 1 

40-6 

39-2 

1817. 

40-8 

440 

42-7 

45  0 

490 

600 

58-7 

56-7 

56-6 

46-3 

48-2 

38-5 

1818. 

40-9 

37-2 

420 

46-7 

53'6 

63-8 

67-2 

64-9 

61-8 

55-0 

50-5 

40-2 

1819. 

41-7 

41-4 

45-1 

49-3 

55-3 

57-3 

62-7 

65- 1 

59-2 

48-8 

42-1 

38-4 

1820. 

33-3 

38-3 

42-4 

50-4 

531 

57-0 

60-5 

59-8 

555 

48-3 

42-7 

41-3 

1821. 

391 

37-4 

43-9 

51-5 

50-5 

55-0 

58-7 

630 

60-7 

51'6 

48-9 

45-7 

1822. 

41-4 

44-7 

48-4 

47-8 

56-9 

63-5 

63-5 

62-6 

57-1 

53-3 

49-5 

37-8 

1823. 

33-4 

39-5 

40-9 

439 

55-7 

56-3 

60- 1 

611 

56-5 

48-9 

44-3 

41-3 

1824. 

39-0 

37-6 

40-6 

44-9 

50-6 

55-9 

63-5 

61-3 

58-8 

511 

47-5 

43-2 

1825. 

400 

39-5 

39-6 

49-8 

54-7 

59-8 

66-2 

63- 1 

61-0 

521 

42-5 

420 

1826. 

33-6 

43-6 

44-3 

50- 1 

511 

63-8 

66-6 

64-7 

57-4 

53-7 

41-2 

43-2 

1827. 

35  0 

330 

44-2 

47-9 

53-8 

58-5 

64-5 

603 

58  0 

531 

42-8 

45-5 

1828. 

41-4 

41-6 

44-6 

47-6 

55-4 

60-9 

62-9 

60-3 

58-6 

51-2 

45-6 

45-9 

1829. 

33-3 

39-8 

40- 1 

44-8 

55-6 

59-9 

61-1 

59-0 

54-3 

48-8 

40-6 

36-3 

1830. 

32-3 

35-6 

46-9 

49-4 

55-8 

56-2 

64  0 

59-5 

54-6 

52-2 

45-7 

36-3 

1831. 

36-0 

42-6 

45-0 

49-2 

53-9 

60-3 

65-3 

64-6 

57-5 

56-3 

456 

43-4 

1832. 

38-9 

38-3 

41-6 

48-3 

52-6 

60- 1 

62'2 

62-3 

57-7 

52-5 

45-0 

43-8 

1833. 

361 

43-8 

38-7 

46-3 

60-5 

60-7 

62  1 

58-8 

54-6 

49-6 

44-8 

46-0 

1834. 

46-0 

41-6 

45- 1 

46-1 

530 

62-0 

651 

63-6 

59-4 

51-8 

45-4 

42-4 

1835. 

39-6 

42-6 

42  1 

47-5 

540 

60-9 

65-4 

64-6 

58-2 

49-3 

44-3 

36-3 

1836. 

38-8 

38-3 

44-8 

44-4 

53-9 

59-9 

63-9 

60-2 

54-5 

48-7 

42-8 

410 

1837. 

38'8 

41-7 

36-9 

40-2 

48-9 

590 

623 

61-4 

561 

51-9 

42-4 

42-6 

1838. 

30'5 

34-3 

42  6 

42-7 

51-8 

58-1 

61-5 

60-9 

55-5 

51-3 

42-1 

400 

1839. 

38-8 

40-5 

401 

420 

510 

59-6 

61-2 

60-2 

56-7 

50-2 

460 

41  0 

1840. 

40-6 

39-5 

38-7 

48-9 

54-6 

55-2 

590 

63-4 

55-2 

48-1 

44-7 

34-7 

1841. 

36-1 

36-6 

47-9 

47-4 

57-9 

57-2 

590 

61-3 

58-5 

50-7 

44-5 

420 

1842. 

34-8 

42-2 

45-4 

45-7 

54-3 

64-2 

61-5 

66-6 

57-5 

47-2 

44-2 

45  3 

1843. 

41-3 

37-5 

43-6 

48-6 

52-8 

56-4 

By  taking  the  means  of  the  numbers  in  this  table  in  different  groups  of  years  the 
next  Table  is  formed. 


MADE  AT  THE  APARTMENTS  OF  THE  ROYAL  SOCIETY. 


311 


Table  II. — Showing  the  mean  temperature  of  the  Air  in  each  month  in  successive 

groups  of  years. 


Period. 

January. 

February. 

March. 

April. 

May. 

June. 

July. 

August. 

September. 

October. 

November. 

December. 

0 

o 

From  1774  to  1781  

35-0 

40-4 

451 

48-0 

54-4 

607 

64-4 

63-8 

581 

510 

430 

40-2 

From  1787  to  1796  

37-5 

40-8 

41-5 

47-3 

527 

57-2 

61-6 

617 

56-8 

50-2 

42-5 

39-1 

From  1797  to  1806  

38-4 

38-9 

41-6 

46-9 

53-4 

58-4 

61-9 

627 

57-8 

49'9 

43-3 

39-9 

From  1807  to  1816  

35-4 

40-1 

41-4 

45-8 

52-8 

57-2 

61-2 

60-8 

57-6 

51-4 

42'3 

40-2 

From  1817  to  1826  

38-6 

40-3 

430 

47-9 

531 

59-2 

627 

62-2 

58-5 

50-9 

457 

411 

From  1827  to  1836  

377 

397 

43-3 

47-2 

54-8 

59-9 

63-6 

61-3 

56  7 

51 -4 

44-2 

41-5 

From  1837  to  1843  

377 

38-9 

421 

45- 1 

531 

58-2 

60-9 

62-3 

56-6 

49-9 

44-6 

40-9 

The  mean  temperature  of  January  from  all  the  observations  is . 
The  mean  temperature  of  February  from  all  the  observations  is 
The  mean  temperature  of  March  from  all  the  observations  is  . 
The  mean  temperature  of  April  from  all  the  observations  is 
The  mean  temperature  of  May  from  all  the  observations  is  . . 

The  mean  temperature  of  June  from  all  the  observations  is.  . 
The  mean  temperature  of  July  from  all  the  observations  is  . . 

The  mean  temperature  of  August  from  all  the  observations  is  . 
The  mean  temperature  of  September  from  all  the  observations  is 
The  mean  temperature  of  October  from  all  the  observations  is 
The  mean  temperature  of  November  from  all  the  observations  is 
The  mean  temperature  of  December  from  all  the  observations  is 
The  mean  of  all  the  monthly  results  is 


37-2 

40-1 

42-5 

46-9 

53-5 

587 

62-4 

62-1 

57*5 

507 

44-0 

40-4 

497 


I shall  not  attempt  to  enter  into  the  discussion  of  periods  of  less  or  greater  heat, 
as  such  can  be  very  readily  seen  in  the  following  Table,  which  is  formed  by  taking 
the  difference  between  the  mean  temperature  of  the  month  derived  from  all  the  ob- 
servations, and  the  mean  temperature  of  the  same  month  in  every  year,  as  contained 
in  Table  I. 


2 s 2 


I 


312 


MR.  GLAISHER  ON  THE  THERMOMETRICAL  OBSERVATIONS 


Table  III. — Showing'  the  excess  of  the  monthly  mean  temperature,  in  every  year, 
above  the  mean  temperature  of  the  month,  as  deduced  from  all  the  years. 


Year. 

January. 

February. 

March. 

April. 

May. 

June. 

July. 

August. 

September. 

October. 

November. 

December. 

1774. 

o 

- 41 

-6-7 

+1'4 

o 

+1-0 

O 

-1-3 

+2-3 

+6-4 

o 

-06 

-i-7 

-6-6 

o 

-3-5 

o 

- 1-9 

1775. 

+ 4-8 

+3-2 

+0-3 

+3-9 

+1-7 

+4-8 

+ 1-6 

00 

+2-0 

-1-2 

-2-5 

+ 0-3 

1776. 

- 8-6 

+ 1-3 

+2-3 

+ 1-4 

-1-8 

+0-9 

+ 1-4 

-0-1 

-1-9 

+21 

0-0 

+ M 

1777. 

- 1-7 

-29 

+3-2 

-1-8 

-01 

-1-5 

-0-9 

+ 1-6 

+ 1-7 

+ 1-9 

+ 1-0 

- 3-2 

1778. 

- 0-8 

-31 

-1-3 

+ M 

+2-4 

+3-5 

+5-6 

+2-7 

-30 

-3-4 

+2-0 

+ 3-8 

1779. 

- 0-8 

+6-6 

+5-6 

+4-9 

+2-3 

+0'2 

+3-5 

+3-1 

+4-3 

+2-5 

-0-8 

+ 1-2 

1780. 

1781. 

- 70 
+ 0-6 

-3-4 
+ 1-6 

+7-8 

+1-2 

-2-2 

+0-3 

+3-7 

+0-7 

+ 1-3 
+4-7 

+ 1-8 
+3-9 

+4-9 

+2-2 

+2-9 

+0-6 

-3-2 

- 2-4 

1787. 

+ M 

+0-8 

+ 1-4 

-1-4 

-11 

0-0 

00 

+0-3 

-2-0 

-0-8 

-31 

+ 0-6 

1788. 

+ 1-8 

0-0 

-2-8 

+3-7 

+3-9 

+0-8 

-0-8 

-0-9 

-0-5 

-0-3 

-2-1 

-100 

1789. 

- 2-2 

+1-2 

-70 

-1-7 

+0-8 

-30 

-2-6 

-0-6 

-1-8 

-2-6 

-40 

+ 2-6 

1790. 

+ 30 

+2-5 

+ 1-8 

-4-9 

+0-2 

-10 

-2-3 

-0-9 

-2-5 

+0-1 

-07 

0-0 

1791.- 

+ 4-2 

+01 

+0-7 

+3-0 

-30 

-02 

-1-9 

+0-6 

+0-4 

-2-8 

-1-4 

- 4-2 

1792. 

- 0-7 

-1-3 

+0-7 

+31 

-2-8 

-3-4 

-2-8 

+ 1-4 

-1-0 

-07 

+0-5 

+ 1-0 

1793. 

- 0-3 

+ 1-0 

-21 

-3-4 

-1-7 

-2-4 

+3-5 

-1-8 

-3-6 

+2-5 

+0-2 

+ 2-0 

1794. 

- 2-3 

+60 

+2-9 

+3-8 

-1-8 

-0-2 

+3-9 

-1-4 

-2-7 

-11 

+0-6 

- 2-2 

1795. 

-11-7 

-4-6 

-2-8 

-0-7 

-0-5 

-41 

-2-5 

00 

+4-4 

+4-0 

-2-0 

+ 5-8 

1796. 

+ 9-7 

+0-9 

-2-4 

+2-5 

-2-3 

-1-7 

-2-8 

-0-9 

+2-7 

-2-9 

-2-4 

- 8-6 

1797. 

- 0-2 

-31 

-3-5 

-11 

-M 

-30 

+ 1-9 

-18 

-1-8 

-2-4 

-1-3 

+ 2-2 

1798. 

+ 2'2 

-0-8 

-0-7 

+3-4 

+ 1-2 

+3-4 

-0-2 

+0-7 

+01 

+0-4 

-27 

- 5-3 

1799. 

- 2-3 

-2-3 

-4-2 

-4-3 

-2-9 

-2-2 

-1-6 

-3-3 

-21 

-21 

+0-2 

- 6-2 

1800. 

+ 1-3 

-4-6 

-3-9 

+2-6 

+ 16 

-2-7 

+ 1-8 

+2-9 

+ 1-5 

-1-5 

-0-5 

- 0-8 

1801. 

+ 3-9 

-02 

+2-7 

-0-4 

+ 1-2 

+0-6 

-0-9 

+ 1-7 

+2-3 

+ 1-5 

-2-5 

- 2-9 

1802. 

- 2-7 

+0-2 

-0-2 

+2-7 

-2-2 

-0-2 

-4-9 

+4-0 

+0-6 

-4-9 

-2-2 

- 1-2 

1803. 

- 2-2 

-2-4 

+0-9 

+2-0 

-2-3 

-16 

+2-3 

+0-9 

-3-7 

-0-5 

-0-8 

+ 4-3 

1804. 

+ 7-6 

-1-8 

-0-3 

-2  1 

+ 4-2 

+3-5 

-1-2 

-09 

+3+ 

+2-0 

+ 1-4 

- 3-4 

1805. 

- 11 

00 

+0-6 

-0-5 

-2-8 

-3-3 

-2-3 

+0-9 

+2-9 

-2-0 

-2-8 

+ 0-5 

1806. 

+ 5-0 

+ 2-8 

-0-7 

-2-8 

+2-6 

+2-0 

-0-2 

+0-6 

+0-6 

+ 1-8 

+4-7 

+ 7-8 

1807. 

+ M 

+1-3 

-4-4 

-0-4 

+2-6 

-01 

+2-1 

+2-9 

-3-3 

+3-6 

-40 

- 2-4 

1808. 

+ 1-4 

-2-4 

-4-3 

-3-3 

+4-7 

+0-2 

+4-3 

+ 1-7 

-11 

-3-3 

+ 1-2 

- 3-0 

1809. 

- 5-2 

+5-4 

+ 1-2 

-4-7 

+3-3 

-0-3 

-1-8 

-1-9 

-0-3 

+0-2 

-3-2 

+ 2-0 

1810. 

- 1-2 

-01 

+0-8 

+0-6 

-2-7 

+0-7 

-0-5 

-0-3 

+30 

+2-4 

+0-1 

- 0-4 

1811. 

- 2-9 

+ 1-2 

+ 15 

+2-1 

+2-9 

-0-7 

-1-4 

-3-2 

+0-8 

4-5-6 

+2-3 

- 0-6 

1812. 

+ 0'3 

+2-9 

-30 

-4-3 

-1-2 

-3-8 

-44 

-3-8 

_0-5 

-0-6 

-2-1 

- 3-9 

1813. 

- 1-2 

+2-9 

+ 1-7 

-2-0 

-0-1 

-2-5 

-2-5 

-2-5 

-1-9 

-2  1 

-2-5 

- 2-4 

1814. 

- 8-7 

-4-7 

-6-3 

+2-3 

-3-8 

-4-4 

-0-3 

-2-2 

_l-5 

-2-1 

-2-0 

+ 2-1 

1815. 

- 3-7 

+2-5 

+3-6 

+0-8 

+2-3 

+0-2 

-1-5 

-0-4 

+5-9 

+2-0 

-3-8 

- 2-0 

1816. 

+ I'l 

-21 

-22 

-2-4 

-3-6 

-4-7 

-6-9 

-2-9 

+2-5 

+ 1-4 

-3-4 

- 1-2 

1817. 

+ 3-6 

+3-9 

-0-2 

-1-9 

-4-5 

+ 1-3 

-3-7 

-5-4 

-0-9 

-4-4 

+4-2 

- 1-9 

1818. 

+ 3-7 

-2  9 

-0-5 

-0-2 

+0-1 

+51 

+4-8 

+2-8 

+4-3 

+4-3 

+6-5 

- 0-2 

1819. 

+ 4-5 

+ 1-3 

+2-6 

+2-4 

+ 1-8 

-4-4 

+0-3 

+3-0 

+ 17 

-1-9 

-1-9 

- 2-0 

1820. 

- 3-9 

-1-8 

-0  1 

+3-5 

-0-4 

-1-7 

-1-9 

-2-3 

-20 

-2-4 

-1-3 

+ 0-9 

1821. 

+ 1-9 

-2-7 

+ 1-4 

+4-6 

-30 

-3-7 

-3-7 

+0-9 

+3-2 

+0-9 

+4-9 

+ 5-3 

1822. 

+ 4-2 

+4-6 

+5-9 

+0-9 

+3’4 

+4-8 

+ 1-1 

+0-5 

-0-4 

+2-6 

+5-5 

- 2-6 

1823. 

+ 3-8 

-0-6 

-1-6 

-30 

+2-2 

-2-4 

-2-3 

-10 

-10 

-1-8 

+0-3 

+ 0-9 

1824. 

+ 1-8 

-2-5 

-1-9 

-20 

-2-9 

-2-8 

+ 1-1 

-0-8 

+ 1-3 

+0-4 

+3-5 

+ 2-8 

1825. 

+ 2-8 

-0-6 

-2-9 

+2-9 

+ 1-2 

+ 11 

+3-8 

+ 1-0 

+3-5 

+ 1-4 

-1-5 

+ 1-6 

1826. 

- 3-6 

+3-5 

+ 1-8 

+3-2 

-2-4 

+5-1 

+4-2 

4-2'6 

-01 

+3-0 

-2-8 

+ 2-8 

1827. 

— 2*2 

-7-1 

+ 1-7 

+ 10 

+0-3 

-0-2 

+21 

- 1-8 

+0-5 

+2-4 

-1-2 

+ 5-1 

1828. 

+ 4-2 

+ 1'5 

+2-1 

+0-7 

+ 1-9 

+2-2 

+0-5 

-1-8 

+ 1-1 

+0-5 

+ 1-6 

+ 5-5 

1829. 

- 3-9 

-0-3 

-2-4 

-21 

+2-1 

+ 1-2 

-1-3 

-3-1 

-3-2 

-1-9 

-3-4 

- 4-1 

1830. 

- 4-9 

— 4*5 

+4-4 

+2-5 

+2-3 

-2-5 

+ 1-6 

-2-6 

-2-9 

+ 1-5 

+ 17 

- 4-1 

1831. 

- 1-2 

+2-5 

+2-5 

+ 2-3 

+0'4 

+ 1-6 

+2-9 

+2-5 

00 

+ 5-6 

+1-6 

+ 3-0 

1832. 

+ 1-7 

-1-8 

-09 

+ 1-4 

-0'9 

+ 1-4 

-0-2 

+0-2 

+0-2 

+ 1-8 

+ 1-0 

+ 3-4 

1833. 

- 11 

+3-7 

-3-8 

-0-6 

+7-0 

+2-0 

-0-3 

-3-3 

-2-9 

-11 

+0-8 

+ 5-6 

1834. 

+ 8-8 

+ 1-5 

+2-6 

-0-8 

-0-5 

+3-3 

+2-7 

+ 1-5 

+ 1'9 

+ 1-1 

+ 1-4 

+ 2-0 

1835. 

+ 2-4 

+2-5 

-0-4 

+0-6 

+0-5 

+2-2 

+3-0 

+2-5 

+07 

-1-4 

+0-3 

- 4-1 

1836. 

+ 1-6 

-1-8 

+2-3 

-2-5 

+0-4 

+ 1'2 

+ 1-5 

-1-9 

-30 

-2-0 

-1-2 

+ 0-6 

1837. 

+ 1-6 

+ 1-6 

-5-6 

-6-7 

-4-6 

+0-3 

-0-1 

-0-7 

-1-4 

+ 1-2 

-1-6 

+ 2-2 

1838. 

- 6-7 

-5-8 

+01 

-4-2 

-1-7 

-06 

-0-9 

-1-2 

-20 

+0-6 

-1-9 

- 0-4 

1839. 

+ 1-6 

+0-4 

-2-4 

-4-9 

-2-5 

+0-9 

-1-2 

-1-9 

-0-8 

-0-5 

+2-0 

+ 0-6 

1840. 

+ 3-4 

-0-6 

-3-8 

+2-0 

+M 

-3-5 

-2-6 

+ 1-3 

-2-3 

-2-6 

+0-7 

- 57 

1841. 

- 11 

-35 

+5-4 

+0-5 

+4-4 

-1-5 

-3-4 

-0-8 

+ 10 

00 

+0-5 

+ 1-6 

1842. 

1843. 

- 2-4 
+ 4-1 

+2-1 

-2-6 

+2-9 
+ 11 

-1-2 
+ 1-7 

+0-8 

-0-7 

+5-5 

-2-3 

-0-9 

+4-5 

00 

-3-5 

+0-2 

+ 4-9 

The  sign  — denotes  that  the  ten)perature  of  that  month  was  below  the  average, 
and  the  sign  + denotes  that  it  was  above  the  average. 


MADE  AT  THE  APARTMENTS  OF  THE  ROYAL  SOCIETY. 


313 


In  the  following  Table  the  mean  temperature  has  been  taken  for  the  quarterly 
periods  ending  March  31,  June  30,  September  30  and  December  31 ; and  for  the  year, 
these  numbers  will  be  immediately  comparable  with  those  now  published  in  the 
Registrar-General’s  Quarterly  and  Annual  Reports. 

Table  IV. — Showing  the  mean  temperature  in  quarterly  periods,  for  the  year,  and 

the  same  for  successive  groups  of  years. 


Year. 

January, 

February, 

March. 

Group 
of  years. 

April, 

May, 

June. 

Group 
of  years. 

July, 

August, 

September. 

Group 
of  years. 

October, 

November, 

December. 

Group 
of  years. 

For  the 
year^ 

Group  of 
years. 

1774. 

38*4 

0 

53-7 

0 

60-0 

O 

43-0 

- 

O 

48-9 

o 

1775. 

42*7 

56*5 

61-8 

43-9 

51-2 

1776. 

38-2 

53-2 

60-5 

46-1 

49-5 

1777. 

1778. 

39-5 

38-2 

>40-2 

51-9 

55-4 

>54-4 

61- 5 

62- 3 

162-1 

44- 9 

45- 8 

U4-7 

49- 4 

50- 5 

^50-2 

1779. 

43-4 

55-5 

64-3 

46-0 

51-5 

1780. 

39*1 

58-0 

63-8 

J 

43-4 

__ 

50-1 

— 

1781. 

41-0 

54-2 

1787. 

41-0 

- 

52*2 

60-1 

43-9 

49-3 

1788. 

39-6 

55-8 

59-9 

40-9 

49-1 

1789. 

37-2 

51-7 

69-0 

43-7 

47-9 

1790. 

42-3 

51*1 

58-8 

44-8 

49-3 

1791. 

1792. 

41-6 

39*5 

>39*9 

52'9 

52-0 

>52-3 

60-3 

59-8 

>60-0 

42-2 

45-3 

>43-9 

49-3 

49-2 

>49-1 

1793. 

39*4 

50-5 

60-0 

46-6 

49-2 

1794. 

42-1 

53-6 

60-6 

44-1 

50-1 

1795. 

33-5 

51-2 

6l-3 

47-6 

48-4 

1796. 

42-6 

-- 

52-3 

J 

60-3 

40-4 

-- 

48-9 

— 

1797. 

37-7 

51-3 

60-1 

44-5 

48-4 

1798. 

40-1 

55*7 

60-9 

42-5 

49-8 

1799. 

37-0 

49-9 

58-3 

42-3 

46-9 

1800. 

37-5 

53-5 

62-7 

44-1 

49-5 

1801. 

1802. 

42-1 

39*0 

>39-7 

53-5 

53-1 

>52-9 

61-7 

60-5 

>60-8 

43-7 

42-3 

>44-4 

50-2 

48-7 

>49-4 

1803. 

39-7 

52-4 

60-5 

46-0 

49-4 

1804. 

41*8 

i 54-9 

60-9 

45-0 

50-7 

1805. 

39-7 

50-8 

61-1 

43-6 

48-9 

1806. 

42-3 

J 

53-6 

J 

61-0 

J 

1 

49-8 

51-7 

1807. 

39-2 

53-4 

61-2 

44-1 

49-6 

1808. 

38*2 

5.3-3 

62-3 

43-3 

49-3 

1809. 

40-4 

52-5 

59-3 

44-7 

49-2 

1810. 

39-8 

52-8 

61-4 

45-7 

49-9 

1811. 

1812. 

39- 9 

40- 0 

>39-1 

54-5 

49-9 

>52-2 

59-4 

57-9 

^59-9 

47-5 

42-8 

>■44-3 

50-3 

47-7 

M8-9 

1813. 

41-1 

51-5 

58-3 

42-7 

48-4 

1814. 

33-3 

51-1 

59-3 

44-4 

47-0 

1815. 

40-7 

54-1 

1 

62-0 

43-7 

50-2 

1816. 

38-9 

J 

49-4 

J 

1 

1 

1 

58-2 

43-9 

47-6 

> 

314 


MR.  GLAISHER  ON  THE  THERMOMETRICAL  OBSERVATIONS 


Table  IV.  (Continued.) 


Year. 

January, 

February, 

March. 

Group 
of  years. 

April, 

May, 

June. 

Group 
of  years. 

July, 

August, 

September. 

Group 
of  years. 

October, 

November, 

1 December. 

Group 
of  years. 

For  the 
year. 

Group 
of  years. 

1817. 

42-5 

O 

O 

51-3 

° 

57-3 

° 

44-°3 

- 

° 

48-9 

O 

1818. 

40-0 

54-7 

64-6 

48-5 

51-9 

1819. 

42-7 

54-0 

62-3 

43-1 

50-5 

1820. 

38-0 

53-6 

58-6 

44-1 

48-5 

1821. 

1822. 

40-1 

44-8 

>40-6 

55- 6 

56- 1 

>53-8 

60-8 

61-1 

>61-4 

48-7 

46-9 

>45-9 

50-5 

52-2 

>50-3 

1823. 

37-9 

52-0 

59-2 

44-8 

48-7 

1824. 

39-0 

50*5 

61-2 

47-2 

49'5 

1825. 

39-7 

54-8 

63-4 

45-5 

50-8 

1826. 

40-1 

J 

55-0 

62-9 

J 

46-0 

5M 

1827. 

37-4 

53-4 

60-9 

47-1 

49-7 

1828. 

42-5 

54-6 

60-6 

47-6 

51-3 

1829. 

37-7 

53-4 

58-1 

I 41-9 

47-8 

1830. 

38-3 

53*8 

59-3 

1 44-7 

49-0 

1831. 

1832. 

41-2 

39-6 

>40-2 

54-4 

53-7 

154-2  j 

62-4 
60-7  ■ 

>60-1 

48-4 

47-1 

>45-8 

51-6 

50-3 

^50-1 

1833. 

39-5 

58-5 

54-5 

46-8 

50-0 

1834. 

44-2 

53-7 

62-7 

46-5 

51-8 

1835. 

41-6 

54-1 

62-7 

43-3 

50-4 

1836. 

40-6 

J 

52-7 

/ 

59-5 

44-1 

- 

49-3 

J 

1837. 

39-1 

49-4 

59-9  ■ 

45-6 

48*5 

1838. 

35-8 

50-8 

59-3 

45-3 

47-8 

1839. 

1840. 

.39-8 

39-6 

>39-4 

50-9 

52-9 

^52-2 

59-4 

56-1 

>59-4 

45-7 

42-5 

>45-1 

48-9 

48-6 

>49-2 

1841. 

40-2 

54-2 

59-6 

45-7 

49-8 

i 

1842. 

40-8 

54-4 

1 

61-9 

45-6 

J 

50-7 

J 

1843. 

40-8 

/ 

52-6 

1 1 

The  mean  temperature  from  all  the  observations 

For  the  quarter  ending  March  . 31  was  39‘8, 

„ June.  . 30  was  53*1, 

„ September  30  was  60*5, 

„ December  31  was  44*8, 

and  for  the  year  from  all  the  observations  was  49°'6. 

By  taking  the  difference  between  these  numbers,  and  those  contained  in  the  pre- 
ceding Table,  the  next  Table  is  immediately  formed. 


MADE  AT  THE  APARTMENTS  OF  THE  ROYAL  SOCIETY. 


315 


Table  V. — Showing  the  excess  of  the  quarterly  and  yearly  mean  temperatures,  in 
every  year,  above  their  means  from  all  the  years. 


Year. 

January, 

February, 

March. 

April, 

May, 

June. 

July, 

August, 

September. 

October, 

November, 

December. 

Whole 

year. 

Year. 

January, 

February, 

March. 

April, 

May, 

June. 

July, 

August, 

September. 

October, 

November, 

December. 

Whole 

year. 

0 

0 

0 

0 

0 

0 

0 

1774. 

— 1-4 

-f  0-6 

-0-5 

-1-8 

-0-7 

1811. 

+ 0-1 

+ 1-4 

— 1-1 

+ 2-7 

+0-7 

1775. 

+ 2-9 

+ 3-4 

+ 1-3 

-0-9 

+ 1-6 

1812. 

+ 0-2 

-3-2 

—2-6 

— 2-1 

-1*9 

1776. 

-1-6 

-l-O-l 

0-0 

+ 1-3 

—0-1 

1813. 

+ 1-3 

-1-6 

— 2-2 

— 2-1 

-1-2 

1777. 

-0-3 

-1-2 

+ 1-0 

+ 0-1 

—0-2 

1814. 

— 6*5 

-2-0 

— 1-2 

— 0-4 

— 2-6 

1778. 

-1-6 

-i-2-3 

+ 1-8 

+ 1-0 

+0-9 

1815. 

+0-9 

+ 1-0 

+ 1-5 

— 1-1 

+ 0-6 

1779. 

-I-3-6 

4-2-4 

+ 3-8 

+ 1-8 

+ 1-9 

I8I6. 

-1-0 

-3-7 

— 2-3 

-0-9 

-2-0 

1780. 

-0-7 

+ 0-9 

+ 3-3 

— 1-4 

+ 0-5 

1817. 

+2-7 

-1-8 

— 3-2 

— 0-5 

-0-7 

1781. 

-I-1-2 

+ 1-1 

1818. 

+0-2 

+ 1-6 

+ 4-1 

+ 3-7 

+ 2-3 

1819. 

+2-9 

+ 0-9 

+ 1-8 

-1-7 

+ 0-9 

1787. 

+ 1-2 

-0-9 

-0-4 

-0-9 

-0'3 

1820. 

-1-8 

+ 0-5 

-1-9 

-0-7 

-1-1 

1788. 

•-0-2 

+ 2-7 

-0-6 

-3-9 

— 0-5 

1821. 

+ 0-3 

+ 2-5 

+ 0-3 

+ 3-9 

+ 0-9 

1789. 

-2-6 

— 1-4 

— 1-5 

— 1-1 

-1-7 

1822. 

+ 5-0 

+ 3-0 

+ 0-6 

+ 2-1 

+ 2-6 

1790. 

+ 2-5 

— 2-0 

-1-7 

0-0 

-0-3 

1823. 

-1-9 

-1-1 

— 1-3 

0-0 

-0-9 

1791. 

+ 1-8 

— 0-2 

-0-2 

-2-6 

— 0-3 

1824. 

— 0-8 

— 2-6 

+ 3-7 

+ 2-4 

-0-1 

1792. 

-0-3 

— 1-1 

-0-7 

+ 0-5 

-0-4 

1825. 

-0-1 

+ 1-7 

+ 2-9 

+ 0-7 

+ 1-2 

1793. 

-0-4 

—2-6 

-0-5 

+ 1-8 

— 0-4 

1826. 

+ 0-3 

+ 1-9 

+ 2-4 

+ 1-2 

+ 1-5 

1794. 

-1-2-3 

+ 0-5 

+ 0-1 

-0-7 

+ 0-5 

1827. 

-2-4 

+ 0-3 

+ 0-4 

+ 2-3 

+ 0-1 

1795. 

-6-3 

-1-9 

+ 0-8 

+ 2-8 

-1-2 

1828. 

+ 2-7 

+ 1-5 

+ 0-1 

+ 2-8 

+ 1-7 

1796. 

-f-2-8 

-0-8 

— 0-2 

— 4-4 

-0-7 

1829. 

-2-1 

+ 0-3 

— 2-4 

-2-9 

— 1-8 

1797. 

—2-1 

— 1-8 

— 0-4 

-0-3 

-1-2 

1830. 

— 1-5 

+ 0-7 

— 1-2 

-0-1 

-0-6 

1798. 

-I-0-3 

+ 2-6 

+ 0-4 

— 2-3 

+ 0-2 

1831. 

+ 1-4 

+ 1-3 

+ 1-9 

+ 3-6 

+ 2-0 

1799. 

— 2-8 

-3-2 

— 2-2 

— 2-5 

-2-7 

1832. 

+ 0-2 

+ 0-6 

+ 0-2 

+ 2-3 

+ 0-7 

1800. 

-2-3 

+ 0-4 

+ 2-2 

-0-7 

-0-1 

1833. 

-0-3 

+ 5-4 

-6-0 

+ 2-0 

+ 0-4 

1801. 

-I-2-3 

+ 0-4 

+ 1-2 

— 1-1 

+ 0-6 

1834. 

+ 4-4 

+ 0-6 

+ 2-2 

+ 1-7 

+ 2-2 

1802. 

-0-8 

0-0 

0-0 

— 2-5 

-0-9 

1835. 

+ 1-8 

+ 1-0 

+ 2-2 

-1-5 

+ 0-8 

1803. 

-1-1 

-0-7 

0-0 

+ 1-2 

-0-2 

1836. 

+ 0-8 

-0-4 

— 1-8 

-0-7 

— 0-3 

1804. 

+ 2-0 

+ 1-8 

+ 0-4 

+ 0-2 

+ 1-1 

1837. 

-0-7 

-3-7 

-0-6 

+ 0-8 

— 1-1 

1805. 

-0-1 

-2-3 

+ 0-6 

— 1-2 

-0-7 

1838. 

-4-0 

— 2-3 

-1-2 

+ 0-5 

-1-8 

1806. 

-t-2-5 

+ 0-3 

+ 0-3 

+ 3-0 

+ 2-1 

1839. 

0-0 

— 2-2 

— 1-1 

+ 0-9 

-0-7 

I8O7. 

-0-6 

+ 0-3 

+ 0-7 

-0-7 

0-0 

1840. 

— 0-2 

— 0-2 

-4-4 

— 2-3 

— 1-0 

1808. 

-1-6 

+ 0-2 

+ 1-8 

-1-5 

-0-3 

1841. 

+ 0-4 

+ 1-1 

-0-9 

+ 0-9 

+ 0-2 

I8O9. 

-f  0-6 

-0-6 

-1-2 

-0-1 

-0-4 

1842. 

+ 1-0 

+ 1-3 

+ 1-4 

+ 0-8 

+ 1-1 

1810. 

0-0 

-0-3 

+ 0-9 

+ 0-9 

+ 0-3 

1843. 

+ 1-0 

— 0-5 

The  sign  — denotes  that  the  period  was  below  the  average,  and  the  sign  + denotes 
that  the  period  was  above  the  average. 

The  numbers  in  the  last  column  of  this  table  indicate  the  excess  or  defect  of  the 


temperature  of  that  year  above  or  below  the  average.  The  year  of  lowest  tempera- 
ture was  1799,  and  every  month  in  this  year  was  below  its  average  value  except  No- 
vember (see  Table  III.).  The  year  of  highest  temperature  was  1822,  which  by 
reference  to  Table  III.,  was  warm  throughout,  the  months  of  September  and  December 
being  those  only  whose  temperatures  were  below  their  averages.  The  mean  tempe- 
rature of  the  year,  therefore,  within  this  period  has  varied  from  46°’9  in  1799  to  52°”2 
in  1822.  The  difference  between  these  numbers  is  5°’S.  This  amount  of  difference 
upon  the  whole  year  is  very  large. 

The  quarterly  values  of  temperature,  as  found  in  the  preceding  tables,  do  not  repre- 
sent the  mean  value  for  any  meteorological  period  ; the  latter  values  always  follow  the 
astronomical  divisions  of  the  year.  In  the  following  Table  the  year  is  supposed  to 


316 


MR.  GLAISHER  ON  THE  THERMOMETRICAL  OBSERVATIONS 


begin  in  March,  so  that  every  year  may  consist  of  one  summer  and  one  entire  winter, 
and  not  of  parts  of  two  winters  with  the  summer  intervening,  therefore — 

Spring  includes  the  months  of  March,  April  and  May ; 

Summer  includes  the  months  of  June,  July  and  August ; 

Autumn  includes  the  months  of  September,  October  and  November ; 

Winter  includes  the  months  of  December,  January  and  February ; 
so  that  winter  consists  of  the  last  month  of  one  civil  year,  and  the  first  two  months 
of  the  following  year. 


Table  VI. — Showing  the  mean  temperature  in  Spring,  Summer,  Autumn  and 
Winter,  and  the  same  for  successive  groups  of  years. 


Spring. 

Summer. 

Autumn.  | 

M'inter. 

Year. 

March, 

April, 

May. 

Group 
of  years, 

June, 

July, 

August. 

Group 
of  years. 

September, 

October, 

November. 

Group 
of  years. 

December, 

January, 

Februaiy. 

Group 
of  years. 

1774. 

48-0 

“*v 

0 

61-7 

-1 

0 * 

48-8 

41-3 

0 

1775. 

49-3 

63-2 

50-2 

36-9 

1776. 

48*3 

6l-8 

50-8 

38-1 

1777- 

1778. 

48-1 

48*4 

>49-1 

60-8 

65-0 

>63-0 

52-3 

49-3 

^507 

36-9 

42-4 

^387 

1779. 

51-9 

63-3 

52-7 

36-2 

1780. 

50-7 

63*7 

50-8 

39-2 

1781. 

48*3 

-- 

64-7 

J 

1787. 

47*3 

61-2 

48*7 

40-0 

1788. 

49*2 

60-7 

49-7 

35-6 

1789. 

45-0 

59-0 

47.9 

41-9 

1790. 

46-7 

59*6 

497 

407 

1791. 

1792. 

47-8 

46-3 

>46-9 

60-5 

59-4 

>60'1 

49- 5 

50- 3 

^49-9 

37*2 

39-8 

>38-9 

1793. 

45-2 

60-8 

50-4 

4M 

1794. 

49-2 

61-8 

49-6 

33-1 

1795. 

46-3 

58-8 

52-9 

447 

1796. 

45-9 

J 

59-3 

49-8 

J 

35-3 

J 

1797. 

45-7 

1 

60-1 

48-9 

40-0 

1798. 

48-9 

62-3 

50-0 

38-6 

1799. 

43-8 

58-7 

49-4 

36-1 

1800. 

47-7 

61-7 

50-5 

40-2 

1801. 

1802. 

48-8 

47-7 

>47-3 

61-5 

60-7 

>60-9 

51-1 

48-5 

>50-3 

37-4 

37-3 

>39-5 

1803. 

47-8 

61-6 

49-1 

42-6 

1804. 

48-2 

61-5 

52-7 

377 

1805. 

46-7 

59-5 

50-1 

42*0 

1806. 

47-3 

61-8 

53-1 

J 

42-6 

1807. 

46-0 

62-6 

- 

47-6 

38-1 

1808. 

46-7 

63-1 

49-6 

38-3 

I8O9. 

47*5 

59*7 

49-6 

39-4 

1810. 

47'2 

57-3 

52-6 

38-5 

1811. 

1812. 

49-8 

44-8 

>46’6 

59-3 

57-2 

>59-4 

1 

53-6 

49-6 

>50-4 

40-1 

38-5 

>38-6 

1813. 

44-2 

58-5 

49-2 

33-9 

1814. 

45-0 

58-7 

48-8 

39-5 

1815. 

50-2 

60-5 

52-1 

38-2 

1816. 

44-9 

56*2 

- 

50-9 

41-3 

MADE  AT  THE  APARTMENTS  OF  THE  ROYAL  SOCIETY. 


317 


Table  VI.  (Continued.) 


Spring. 

Summer. 

j Autumn. 

Winter. 

Year. 

March, 

April, 

May. 

Group 
of  years. 

June, 

July, 

August. 

Group 
of  years. 

1 September, 
October, 

, November. 

Group 
of  years. 

December, 

January, 

February. 

Group 
of  years. 

1817- 

44-5 

-> 

0 

58-4 

0 

i 50-3 

O 

38-9 

1818. 

47-4 

65-3 

! 55-7 

4M 

1819. 

49-9 

61-7 

50-0 

36-7 

1820. 

48-6 

59-1 

48-8 

39*3 

1821. 

1822. 

48-6 

51-0 

>47-9 

58-9 

63-2 

>61-4 

53-7 

53-3 

>51*7 

43-9 

36-9 

:>40-4 

1823. 

46-8 

59-2 

49-9 

39-3 

1824. 

45*3 

60-2 

52*5 

40-9 

1825. 

48-0 

63-0 

51-0 

39-7 

1826. 

48-5 

J 

65-0 

J 

50-8 

J 

37-1 

1827. 

48-6 

61-1 

51-6 

42-8 

1828. 

49-2 

61-4 

51*8 

39-6 

1829. 

46-8 

60-0 

47*9 

34-7 

1830. 

50-7 

59-9 

50-8 

38*3 

1831. 

1832. 

49-3 

47-5 

>48-4 

63-4 

61*5 

>61-6 

53-1 

51-7 

>50-8 

40- 2 

41- 2 

>40*1 

1833. 

48-5 

59-8 

49-7 

44*5 

1834. 

48-1 

63-5 

52-2 

41*5 

1835. 

47-9 

63-6 

50-6 

37-8 

1836. 

47-7 

61*3 

- 

48-6 

— 

40-5 

- 

1837. 

42-1 

60-9 

50-1 

35-8 

1 

1838. 

45-7 

60-2 

50-5 

39-8 

1839. 

1840. 

44-4 

47*4 

>46-8 

60*3 

59-4 

>60-7 

50-9 

49-3 

>49-7 

40-3 

35-8 

>38-7 

1841. 

51-1 

59*2 

51-2 

39-6 

1842. 

48-5 

64-1 

J 

46-3 

41*3 

1843. 

48-3 

The  mean  temperature  for  Spring  from  all  the  observations  was  ....  47'6 

The  mean  temperature  for  Summer  from  all  the  observations  was  . . . 6 TO 

The  mean  temperature  for  Autumn  from  all  the  observations  was  . . . 50’5 

The  mean  temperature  for  Winter  from  all  the  observations  was  . . . 39'3 

The  mean  temperature  for  the  Year  from  all  the  observations  was  . . . 49'6 


By  taking  the  difference  between  the  mean  temperature  of  each  period  from  all  the 
observations,  and  the  mean  temperature  for  the  same  period  in  every  year,  the  follow- 
ing Table  was  formed. 


2 T 


MDCCCXLIX. 


318 


MR.  GLAISHER  ON  THERMOJVIETRICAL  OBSERVATIONS. 


Table  VII. — Showing-  the  excess  of  the  mean  temperature  in  Spring,  Summer,. 
Autumn  and  Winter,  in  every  year,  above  the  mean  temperature  for  the  period. 


1 Year. 

Spring. 

Summer. 

Autumn. 

Winter. 

Year. 

Spring. 

Summer. 

Autumn. 

Winter. 

0 

0 

0 

0 

0 

0 

0 

0 

1774. 

+ 0-4 

4-0-7 

-1*7 

-2-0 

1811. 

+ 2-2 

-1-7 

+ 3-1 

+ 0*8 

1775. 

+ 1-7 

4-1-2 

— 0-3 

— 2-4 

1812. 

-2-8 

— 3-8 

-0-9 

— 0-8 

1776. 

+ 0-7 

-1-0-8 

+ 0-3 

— 1-2 

1813. 

— 3-4 

-2-5 

— 1-3 

— 5-4 

1777. 

+ 0-5 

-0-2 

+ 1-8 

— 2-4 

1814. 

—2-6 

-2-3 

-1-7 

+ 0-2 

1778. 

-I-0-8 

-1-4-0 

— 1-3 

+ 3-1 

1815. 

+ 2-6 

-0-5 

+ 1-6 

— 1-1 

1779. 

+ 4-3 

4-2-3 

+ 2-2 

— 3-1 

1816. 

-2-7 

-4-8 

+ 0-4 

+ 2-0 

1780. 

1781. 

+ 3-1 
+ 0-7 

-h2-7 
+ S-7 

+ 0-3 

— 0-1 

1817. 

1818. 
I8I9. 

-3-1 
-0-2 
+ 2-3 

— 2-6 
+ 4-3 
+ 0-7 

-0-2 
+ 5-2 
-0-5 

-0-4 
+ 1-8 
— 2-6 

1787. 

-0*3 

+ 0-2 

— 1-8 

+ 0-7 

1820. 

+ 1-0 

-1-9 

-1-7 

0-0 

1788. 

+ 1-6 

-0-3 

-0-8 

-3-7 

1821. 

+ 1-0 

—2-1 

+ 3-2 

+ 4*6 

1789. 

—2-6 

— 2-0 

— 2-6 

+ 2-6 

1822. 

+ 3-4 

+ 2-2 

+ 2-8 

3.4 

1790. 

+ 0-9 

-1-4 

— 0-8 

+ 1-4 

1823. 

— 0-8 

-1-8 

— 0-6 

0-0 

1791. 

-f-0-2 

— 0-5 

— 1-0 

— 2-1 

1824. 

— 2-3 

-0-8 

+ 2-0 

+ 1-6 

1792. 

-1*3 

-1-6 

— 0-2 

+ 0-5 

1825. 

+ 0-4 

+ 2-0 

+ 1-5 

+ 0-4 

1793. 

— 2-4 

— 0-2 

-0-1 

+ 1-8 

1826. 

+ 0-9 

+ 4-0 

+ 0-3 

-2-2 

1794. 

+ 1-6 

-fO-8 

-0-9 

-6-2 

.1827. 

+ 1-0 

+ 0-1 

+ 1-1 

+ 3-5 

1795. 

— 1-3 

— 2-2 

+ 2-4 

+ 5-4 

1828. 

+ 1-6 

+ 0-4 

+ 1-3 

+ 0-3 

1796. 

-1-7 

-1-7 

-0-7 

-4-0 

1829. 

-0-8 

-I'O 

—2-6 

-4-6 

1797. 

-1-9 

-0-9 

-1-6 

+ 0-7 

1830. 

+ 3-1 

-M 

+ 0-3 

-1-0 

1798. 

+ 1-3 

+ 1-5 

-0-5 

-0-7 

1831. 

+ 1-7 

+ 2-4 

+ 2-6 

+ 0-9 

1799. 

-3*8 

-2-3 

— 1-1 

-3-2 

1832. 

-0-1 

+ 0-5 

+ 1-2 

+ 1-9 

1800. 

+ 0-1 

+ 0-7 

0-0 

+ 0-9 

1833. 

+ 0-9 

— 1-2 

— 0-8 

+ 5-2 

1801. 

-hl'2 

+ 0-5 

+ 0-6 

-1-9 

1834. 

+ 0-5 

+ 2-5 

+ 1-7 

+ 2-2 

1802. 

+ 0*1 

— 0-3 

—2-0 

0-0 

1835. 

+ 0-3 

+ 2-6 

+ 0-1 

-1-5 

1803, 

+ 0-2 

+ 0-6 

— 1-4 

+ 3-3 

1836. 

+ 0-1 

+ 0-3 

-1-9 

+ 1-2 

1804. 

+ 0-6 

+ 0-5 

+ 2-2 

-1-6 

1837. 

— 5-5 

-0-1 

-0-4 

— 3-5 

1805. 

-0-9 

— 1-5 

-0-4 

+ 2-7 

1838. 

-1-9 

— 0-8 

0-0 

+ 0-5 

1806. 

— 0-3 

+ 0-8 

+ 2-6 

+ 3-3 

1839. 

-3-2 

-0-7 

+ 0-4 

+ 1-0 

1807. 

-1-6 

+ 1-6 

-2-9 

-1-2 

1840. 

— 0-2 

-1-6 

— 1-2 

-3-5 

1808. 

-0*9 

+ 2-1 

-0-9 

-1-0 

1841. 

+ 3-5 

-1-8 

+ 0-7 

+ 0-3 

1809. 

1810. 

— 0*1 
-0-4 

— 1-3 
-3-7 

-0-9 
+ 2-1 

+ 0-1 
— 0-8 

1842. 

1843. 

+ 0-9 
+ 0-7 

+ 3-1 

4-2 

+ 2-0 

The  sign  — denotes  that  the  mean  temperature  for  that  period  was  below  the 
average,  and  the  sign  + denotes  that  it  was  above  the  average. 

It  will  be  seen  that  hitherto  the  mean  temperature  at  Somerset  House  has  been 
estimated  a great  deal  too  high ; in  almost  every  case  the  corrections  have  reduced 
the  temperature.  I have  not  in  this  paper  discussed  the  question  whether  the  tem- 
perature, as  now  determined,  is  too  high  for  the  latitude  and  elevation  of  Somerset 
House.  This  discussion  will  be  necessary  when  I attempt  to  connect  the  series  at 
Greenwich  (which  I look  upon  as  merely  a continuation  of  that  taken  at  the  Royal 
Society)  with  these  results.  I have  already  made  some  progress  in  this  investiga- 
tion, and  hope  in  a short  time  to  present  to  the  Society  the  results  of  my  labours, 
and  to  give  similar  results  to  those  in  this  paper  brought  up  to  the  present  time.  At 
some  future  time  I hope  to  be  able  to  reduce  the  barometrical  observations  in  a 
similar  manner,  the  results  from  which  will  be  of  great  value  ; for  although  there  has 
been  neglect  in  stating  at  different  times,  what  corrections  have,  and  what  have  not 
been  applied,  yet  I think  they  admit  of  the  deduction  of  valuable  results. 


[ 319  ] 


XVII.  On  the  Meteorology  of  the  Lake  District  of  Cumberland  and  Westmoreland ; 
including  the  results  of  Experiments  on  the  fall  of  Rain  at  various  heights,  up  to 
3166  feet  above  the  sea  level. 

By  John  Fletcher  Miller,  Esq.,  F.R.A.S. 

Communicated  by  Lieut.-Col.  Sabine,  For.  Sec.  R.S. 

Received  February  19, — Read  April  19,  1849. 

The  form  of  the  instruments,  their  positions,  &c.,  are  fully  described  in  a former 
paper,  read  before  the  Royal  Society  on  the  18th  of  May  1848. 

The  Roman  numerals  attached  to  each  gauge  refer  to  corresponding  numbers  on 
a map  of  the  Lake  District  accompanying  the  said  paper. 

With  one  exception,  elsewhere  referred  to,  no  accident  of  any  importance  has 
occurred  to  interrupt  the  continuity  or  correctness  of  the  rain  tables.  Indeed,  con- 
sidering the  extent  of  the  experiments,  and  the  exposed  position  of  many  of  the  in- 
struments, mishaps  of  any  kind  have  from  the  first  been  exceeding  rare.  The  gauges 
are  all  under  my  own  supervision ; the  registrars  are  all  thoroughly  instructed  in  the 
method  of  reading  off  the  rain,  which  is  regularly  recorded  in  registers  prepared  for 
the  purpose ; and,  being  all  careful  persons,  and  almost  constantly  on  the  spot,  the 
observations  are  seldom  omitted  even  for  a single  day. 

The  records  are  transmitted  to  me  at  the  close  of  each  month,  and  are  entered  in 
collateral  columns  in  a large  folio  journal ; should  there  be  any  apparent  discrepancy 
at  any  station  on  any  particular  day  or  days,  an  explanation  is  requested,  and  the 
original  register  examined,  to  ascertain  whether  the  transmitted  copy  is  correct.  In 
this  way,  errors  have  occasionally,  though  very  rarely,  been  discovered,  and  I do  not 
recollect  that  one  such  has  occurred  during  the  past  year. 


The  Observatory,  Whitehaven, 
February  Q,  1849. 


2 T 2 


i 


Fahlr  I. Synopsis  of  the  Fall  of  Rain  in  the  Lake  Districts  of  Cumberland  and  Westmoreland,  for  the  year  1848. 


320 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


•j([lBp  SUOIJBAJ9SqO  OAiJ 
‘;sBOO  9q?  jv 

S.E.&S.W. 

•a 

i 

t/j 

N.E. 

N.E. 

S.W. 

S.W. 

i 

p; 

CO 

s.w. 

c 

ci 

z 

CO 

S.W. 

1 ^ 

1 ^ 

1 bo 

1 -S 

1 ^ 

> 

u 

•iillBp  nOTJBAa9SqO  9U0 

‘9XlBAiqjB9S  JV 

variable. 

i 

tfi 

variable. 

i 

CA 

CO 

i 

CO 

C 

cS 

> 

CO 

s.  var. 

N.W.&S.W. 

i 

CO 

i 

CO 

i 

CO 

PU 

•iijTBp  SUOllBAJasqO  OA\J 
‘93jBa  2[OoaiOTnj3  jy 

i 

tf) 

c« 

(d 

CO 

xh 

CO 

> 

CO 

CO 

N.w.var. 

S.  & S.E. 

i 

CO 

westerly 

XX. 

•95i'CAvq59U05s 

in. 

7-86 

i 

22-90 

1 

98-8 

CO 

CO 

o 

CO 

9-82 

14-34 

98-01 

X 

X 

14-27 

11-38 

19-05 

130-24 

106-21 

XIX. 

o 

h» 

o 

OJ 

*c3 

•9DBJJnS  9qj  OAOqB 
S9qoui  81  ‘pfOia  ui 

in. 

9-63 

29-98 

11-18 

4-12 

oi 

11-19 

CO 

lO 

13-54 

Ol 

c; 

50 

X 

50 

13-54 

19-81 

lO 

126-80 

XVIII. 

n 

■5 

rt 

CO 

•90Bjins  9qj  9A0qB 
saqout  9 ‘uapiBO  uj 

50 

.S^ 

30  55 

98-11 

4-19 

3-05 

08-11 

50 

13-91 

7-00 

17-32 

14-07 

0 

01 

160-89 

129-24 

143-51 

151-87 

1 XVII. 

•B9S  9qj  9A0qB 

433J  6 095  ‘p^^H  ^l^pSUBl 

in. 

701 

25-67 

9-71 

Ol 

c^: 

CO 

2-11 

9-86 

01 

bi 

11-41 

X 

13-53 

13-13 

50 

l‘>. 

130-38 

lO 

Ci 

bi 

127-40 

136  00 

XVI.  1 

flj 

(x 

0 

1 

•*B9S  9qj 

9AoqB  J99J  o6[  ‘9pis9xqruv 

in. 

4-72 

14-19 

CO 

2-30 

2-03 

lb 

6-18 

7-16 

o 

X 

bi 

9-89 

99-9 

10-06 

CO  : : : 

iC  - • • 

• • • 

*>•**• 

> 

X 

1 

•B9S  9qj  9A0qB  J99J  1 008 

‘5[09q:inoJX  ‘aioh  aqx 

in. 

5*922 

CO 

o 

C5 

CO 

00 

50 

1-927 

01 

X 

X 

50 

080-9 

X 

X 

lO 

Ol 

cb 

9-357 

lO 

c> 

Ci 

12-295 

91-347 

o 

o 

X 

o* 

77-719 

lO 

cp 

50 

»p 

lb 

Ol 

XIV.  j 

•t38S  9t[5 

aAoqB  ^93^  ggi  ‘p'egH 

in. 

606 

19*92 

9-15 

3-24 

1-54 

t>. 

X 

C5 

1066 

10-74 

5-47 

11-88 

11-10 

15-69 

115-32 

96-34 

106-93 

108-55 

1 

41*51 

XIII. 

S 

Head 

of 

Vale. 

in. 

6-35 

14-22 

o 

50 

01 

X 

1-83 

6 34 

8-42 

3 99 

06-6 

*>. 

11-03 

86-78 

74-93 

XII. 

W 

Centre 

of 

Vale. 

in. 

4-92  , 

o 

50 

1-87 

1-01 

CO 

50 

5-98 

7-45 

3-72 

CO 

CO 

50 

70-38 

58-66 

X 

•BOS  9q) 

9A0qB  199^  9oS  ‘q;JuSs9;B9 

175 

24-78 

X 

354 

3-17 

8-31 

13-66 

11-37 

5-43 

Ol 

>b 

12-40 

lo 

CO 

X 

13355 

106-25 

121-90 

124-13 

Ci 

CO 

•BOS  9q5  9A0qB  ?99J  £SZ 
jjooinuinjo  jo  400^ 

in. 

7*30 

CO 

«>. 

50 

CO 

X 

01 

1 52 

10-41 

CO 

C5 

4-63 

r 

7-62 

o 

98-07 

■ 

(M 

Cp 

bj 

X 

X 

50 

Ci  X 

o 

CO 

X 

•B9S  9q:^ 

9AoqB  :)99j  get;  ‘a9;BA\S9Ai07 

GO 

■sS 

12-971 

5-706 

1-627 

1-175 

6-236 

7-431 

»o 

C5 

*>.. 

W 

3-755 

8-134 

6 552 

10  102 

X 

j c5 

1 50 

I 

66296 

79-249 

69-542 

25-650 

VIII. 

•B9S  9qi  9A0qB  ^99^  QgZ 
‘9tBpj9UUa  ‘94lBAiq3J9niO  JO  9^^ 

in. 

7-20 

16-93 

o 

CO 

3-00 

3-40 

50 

50 

X 

lO 

C5 

50 

Ol 

b; 

50 

cp 

o 

9-60 

10-74 

97-73 

CO 

O 

X 

X 

X X 

cb  50 

X t>«. 

50 

A. 

Ol 

> 

•B9S  atn  aAoqx!  laaj  852  ‘qoiAisaji 

in. 

4112 

10-276 

4-736 

1-722 

oi 

50 

O 

5-036 

6-246 

6-280 

2-104 

X 

lO 

CO 

O 

50 

10-972 

o 

50 

50 

58-286 

67-678 

62-202 

X 

07 

> 

•B9S  9qj  9AOqB 

OIS  ‘SIITJH  9Jl«AiqjU9SSBa 

in. 

3*42 

8-11 

3-00 

2-23 

CO 

lO 

3-53 

3-45 

4-72 

2-21 

5-12 

4-77 

Ci 

lb 

50 

O 

44-45 

: 

> 

•mn0UII93lD03 

in. 

3*80  , 

CO 

C5 

3-80 

1-00 

4-36 

4-10 

CO 

bi 

4-44 

4-80 

5-81 

52-37 

42-55 

— CO 

Ci 

bl  50 

lO 

> 

•n9ABq94tqA\ 

q^Tios  S9|iui  99jqj  ‘qsoxa  9qx 

in. 

4*34 

9-82 

X 

CO 

X 

2 23 

5-24 

4-60 

8-07 

Ol 

bi 

8-36 

4-07 

5-12 

60-82 

O 

GO 

55-16 

53-00 

cp 

Ci 

•B9S  9q5  9A0qB  J99J  Si 
‘9Xd995S  qOJTiqa  S^S9lUBf  ‘JS 

in. 

3-303 

6-397 

3-498 

■293 

1-452 

3-043 

2-442 

X 

X 

1-723 

4-632 

2-186 

3-187 

36-344 

30-713 

35-422 

33-489 

14-550 

S 

1 

•BOS  oqj  9A0qB 
jaaj  osf’  ‘9SO|0  punoa 

in. 

3-735 

7-986 

3-930 

C5 

CO 

CO 

1-612 

4-041 

3-862 

o 

»b 

2-122 

50 

50 

lb 

3-412 

4-484 

o 

o 

w 

50 

42-023 

I? 

•BOS  9q3 

OAoqu  ;d9j  o6  H^ih 

in. 

3-745 

7-815 

X 

X 

•495 

1-798 

50 

X 

CO 

3-630 

5-054 

2-266 

Ol 

lb 

3-507 

1 

' 4*805 

47-342 

42-921 

49-134 

49-207 

18-561 

6 

1848. 

January  ... 

1 February . . 

1 March  .... 

1 April 

a 

1 June 

July 

1 August ..... 

1 September 

October  ... 

1 November. 

Decemlier. 

X 

X 

1847. 

1846. 

1845. 
1844,  I 
July  to 
December  J 

The  gauge  at  Grasmere,  which  in  the  Tables  and  Map  accompanying  the  Report  for  1847  was  marked  No.  XVI.,  has  been  discontinued,  and  Ambleside  is 
ted  in  its  place. 


DISTRICT  OF  CUiMBERLAND  AND  WESTMORELAND. 


3*21 


Table  II. 


Wet  Days. 


1848. 

C 

0) 

> 

a 

The  Flosh. 

Cockermouth. 

Bassenthwaite 

Halls. 

Keswick. 

Loweswater 

Lake. 

Crum  mock 

Lake. 

Eskdale. 

Wastdale  Head. 

Troutbeck. 

Laiig'dale  Head. 

<y 

c5 

O) 

cn 

Stonethwaite. 

January  ... 

13 

13 

15 

14 

15 

10 

12 

11 

15 

7 

13 

14 

14 

February... 

23 

23 

25 

25 

23 

25 

23 

22 

24 

23 

23 

25 

23 

March 

23 

22 

25 

19 

26 

26 

23 

24 

26 

26 

24 

24 

24 

April  

16 

12 

16 

13 

16 

13 

12 

14 

18 

13 

13 

16 

16 

May  

6 

7 

6 

4 

10 

8 

6 

6 

8 

10 

7 

11 

11 

June  

19 

19 

20 

17 

20 

18 

19 

19 

22 

18 

20 

19 

21 

Jnly 

18 

18 

19 

15 

17 

18 

17 

17 

21 

16 

18 

19 

18 

August  ... 

19 

23 

23 

18 

23 

23 

24 

23 

25 

24 

24 

25 

22 

September . 

13 

11 

15 

11 

10 

14 

14 

10 

16 

10 

12 

16 

13 

October  ... 

22 

22 

24 

26 

27 

23 

21 

21 

24 

18 

21 

22 

23 

November.. 

20 

20 

22 

18 

24 

21 

18 

21 

23 

18 

19 

22 

21 

December.. 

18 

17 

18 

16 

.8 

18 

18 

17 

21 

18 

18 

19 

18 

1848. 

210 

207 

228 

196 

229 

217 

207 

205 

243 

201 

212 

232 

224 

1847. 

191 

183 

210 

199 

204 

190 

199 

226 

188 

209 

202 

195 

1846. 

200 

208 

234 

213 

198 

216 

234 

194 

213 

219 

1845. 

193 

175 

212 

195 

195 

202 

211 

180 

211 

Table  III. 

Showing-  the  Quantity  of  Rain  received  by  the  Mountain  Gauges  in  thirteen  months, 
between  the  1st  of  December  1847,  and  the  31st  of  December  1848. 


No. 

XXL 

XXII. 

XXIII. 

XXIV. 

XXV. 

XIV. 

XIII. 

XXVI. 

XIX. 

1848. 

Sea  Fell, 
31G6  feet 
above  the  sea. 

Great 
Gabel, 
2925  feet 
above  the 
sea. 

Sparkling 
Tarn, 
1900  feet 
above  the 
sea. 

Stye  Head, 
1290  feet 
above  the 
sea. 

Brant 

about 
500  feet 
above  the 
sea. 

Valley. 

Borrowdale. 

To  the  west, 
Wastdale, 
166  feet 
above  the 
sea. 

To  the 
south-east, 
Eskdale, 
height 
unknown. 

Seatollar 
Common, 
1334  feet 
above  the 
sea. 

The  Valley, 
Seathwaite, 
242  feet 
above  the 
sea. 

December.. 

1848. 

January  ... 
February... 

March 

April  

May  

June  

July 

August  ... 
September.. 
October  ... 
November.. 
December.. 

in. 

*4-42 

8- 58 

10-65 

9- 74 

5- 11 

10-96 

6- 81 

8-46 

in. 

Frozen') 

Frozen 
Frozen  j 
28-00 J 
2-29 
2-60 
9-00 
10-32 
9-79 

5- 39 
9*71 

6- 17 
8-05 

in. 

Frozen J 

Frozen  7 
39-45  j 

8-04 

2- 31 

3- 72 
11-52 
17-40 
13-09 

8-16 

17-06 

11-44 

16-40 

in. 

Frozen. 

Frozen. 

41-31 

9-17 

3-22 

3-10 

9-40 

13- 18 

12- 31 
7-51 

14- 85 
11-34 

13- 33 

in. 

Frozen  "1 

Frozen  | 
32-65  J 
9-36 
5-84 
1-98 
7-80 
8-12 
9-16 
4-76 
11-36 
9-36 
8-80 

in. 

12-15 

6-06 

19-92 

9-15 

3-24 

1-54 

9-87 

10-66 

10- 74 
5-47 

11- 88 
11-10 
15-69 

in. 

8-93  J 

6-35  f 
14-22  J 
6-70 
2-82 
1-83 

6- 34 

7- 21 

8- 42 
3-99 

9- 90 
7-97 

11-03 

in. 

12- 53 

Frozen. 

34-18 

7-10 

2-07 

2-80 

10-00 

15-00 

11- 55 
5-42 

13- 20 

12- 63 

13- 00 

in. 

20-33 

9-63 
29-98 
11-18 
4-12 
2-97 
11-19  1 

17-53 
13-54 
6-92 
16-81 
13-54 
19-81 

Inches... 

64-73  1 

From  May  J 

91-32 

148-59  1 138-72 

109-19 

127-47 

95-71  1 

1 

139-48 

177-55 

* The  fall  of  rain  at  this  station,  during  the  winter  of  1847-48,  was  lost,  in  consequence  of  injury  sustained 
by  the  receiver  from  the  frost. 


322 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


Table  IV. — For  the  Summer  Months. 


No. 

XXL 

XXII. 

XXIII. 

XXIV. 

XXV. 

XIV. 

XIII. 

XXVI. 

XIX. 

Val 

ey. 

Borrowdale. 

Sea  Fell, 

Great 

Sparkling 

Stye  Head, 

Brant  Rigg, 

3166  feet 

Gabel,  2925 

Tarn,  1900 

1290  feet 

about  500 

o eatuliai 

i.  lie  V alley  9 

1848. 

above  the 

feet  above 

feet  above 

above  the 

feet  above 

To  the  west 

To  the 

Common, 

Seathwaite, 

sea. 

the  sea. 

the  sea. 

sea. 

the  sea. 

of  Wast- 
dale 

south-east 
of  Eskdale. 

1334  feet 
above  the 

242  feet 
above  the 

sea. 

sea. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

May  

4-42 

2-60 

3-72 

3-10 

1-98 

1-54 

1-83 

2-80 

2-97 

June  

8*58 

9-00 

11-52 

9-40 

7-80 

9-87 

6-34 

10-00 

11-19 

July  

10-65 

10-32 

17-40 

13-18 

8-12 

10-66 

7-21 

15-00 

17-53 

August  

9-74 

9-79 

13-09 

12-31 

9-16 

10-74 

8-42' 

11-55 

13-54 

September  

5-11 

5-39 

8-16 

7-51 

4-76 

5-47 

3-99 

5-42 

6-92 

October  

10-96 

9-71 

1706 

14-85- 

11-36 

11-88 

9-90 

13-20 

16-81 

Inches 

49-46 

46-81 

70-95 

60-35 

43-18 

50-16 

37-69 

57-97 

68-96 

Table  V. — For  the  Winter  Months. 


1847. 

Sea  Feu. 

Great 

Gabel. 

Sparkling 

Tarn. 

Stye  Head. 

Brant 

Rigg- 

The  Valley. 

Borrowdale. 

To  the  west 
of  Wast- 
dale. 

To  the 
south-east 
of  Eskdale. 

Seatollar 

Common. 

Valley. 

Seathwaite. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

in. 

December  

Frozen" 

Frozen" 

Frozen 

Frozen 

12-53 

20-33 

1848. 

January  

Frozen 

Frozen 

Frozen 

Frozen 

> 

Frozen 

9-63 

February  

Frozen 

> 

39-45 

41-31 

32-65 

38-13 

29-50 

34-18 

29-98 

March 

28-00 

8-04 

9-17 

9-36 

9-15 

6-70 

7-10 

11-18 

April  

2-29 

2-31 

3-22 

5-84 

3-24 

2-82 

2-07 

4-12 

Noyember  

6-81 

6-17 

11-44 

11-34 

9-36 

11-10 

7-97 

12-63 

13-54 

December  

8-46 

8-05 

16-40 

13-33 

8-80 

15-69 

11-03 

13-00 

19-81 

Inches 

44-51 

77-64 

78-37 

66-01 

77-31 

58-02 

81-51 

108-69 

DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


323 


Table  VI. — Temperature  at  Seathwaite  taken  by  Self-registering  Thermometers 

made  by  Watkins  and  Hill. 


1848. 

Absolute. 

Mean  of 
max. 

Mean  of 
min. 

Approxi- 

mate 

mean 

tempera- 

ture. 

Mean 
at  9 A.M. 

On  grass. 

Prevailing  winds. 

Max. 

Min. 

Min. 

Mean. 

Radiation. 
Max.  j Mean. 

January  

February  

March 

April  

May  

June  

July  

August  

September 

October  

November  

December  

O 

50 

49-5 

57-5 

67 

72-5 

75 

79 

62-5 

68 

60-5 

52 

56 

O 

9 

25 

27 

28- 5 

32 

40 

45 

41-5 

38-5 

29- 5 

24 

26 

3^43 

44-50 

46-66 

52-78 

63-52 

63-86 

62-61 

57-99 

57-93 

50-17 

44-59 

43-76 

2?50 

36-67 

34-14 

38-03 

48- 20 
50-75 
53-32 

49- 87 
49-05 
43-66 

36- 35 

37- 21 

32-46 

40-58 

40-40 

45- 40 
55-86 
57-30 
57-96 
53-93 
53-49 

46- 91 
40-47 
40-48 

32-71 

40-24 

39- 67 

45- 35 
55-89 
57-18 
57-19 
53-48 
52-28 

46- 61 

40- 13 
40-43 

^-5 

19 

19-5 

21 

24 

29 

32 

29 

25-5 

18 

12 

11 

24-56 

33-74 

29-44 

32-38 

38- 40 
42-36 
46-27 
40-79 

39- 76 
36-01 
29-63 
28-86 

O 

7 

7 

8-5 

10-5 

15 

15 

14 

15-5 

16 

14-5 

13-5 

18-7 

2-93 

2-93 

4- 81 

5- 65 
9-80 

8- 41 
7-05 

9- 08 
9-28 

7- 96 

6- 72 

8- 38 

Var. 

w. 

w.  and  s.w. 
Var. 

w. 

s.w. 

s.w. 

s.w. 

s.w.  var. 

s.  var. 

N.w.  and  s.w. 

s.w. 

Means  at  1 

Whitehaven  J 

62-4  1 30-5 

62-5  ! 33-0 

52- 15 

53- 62 

42-06 

44-00 

47- 10 

48- 81 

46-76 

20-5 

23-1 

35-18 

37-24 

12-9 

6-91 

6-76 

s.w. 

Var. 

Difference  

Difference  in  "I 
1847 / 

0-1 

0-5 

2- 5 

3- 8 

1-47 

0-96 

1-94 

1-46 

1-71 

1-22 

2-6 

2-06 

0-15 

Remarhs. 

The  fall  of  rain  in  the  Lake  District  during  the  year  1848,  greatly  exceeds  the 
amount  in  any  other  year  since  the  register  was  commenced  in  1844 ; and  the  same 
remark  applies  to  the  number  of  wet  days.  The  total  depth  in  1848,  at  Seathwaite, 
the  wettest  station,  is  160-89  inches,  and  of  this  quantity,  114-32  inches  fell  in  the 
six  months  comprehending  February,  July,  August,  October,  November  and  De- 
cember. 

The  wettest  quarter  of  the  year  was  the  last,  in  which  52-10  inches  were  measured  ; 
the  wettest  month  in  1848  was  February,  which  yielded  30-55  inches,  by  far  the  largest 
quantity  ever  measured  in  any  month  in  this  country;  and  the  two  wettest  days 
were  the  3rd  and  26th  of  December,  when  4-60  and  4-22  inches  respectively,  were 
read  off. 

At  Seathwaite,  there  have  been  forty-eight  days  in  last  year  wherein  the  quantity 
of  rain  fallen  was  between  half  an  inch  and  1 inch  ; thirty-two  days  between  1 and 
2 inches  ; thirteen  days  between  2 and  3 inches  ; five  days  between  3 and  4 inches  ; and 
two  days  between  4 and  5 inches. 

In  a former  paper  which  I had  the  honour  to  lay  before  the  Royal  Society,  I 
endeavoured  to  give  a general  outline  of  the  meteorology  of  the  Lake  District,  as  far 
as  the  facts  then  ascertained  would  permit.  I now  proceed  to  discuss  one  or  two 
points  which  were  intentionally  passed  over  in  that  report. 

The  mountains  flanking  the  Lake  District  valleys,  generally  increase  in  altitude 


324 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


with  great  regularity,  towards  the  head  or  eastern  extremity  of  the  vale ; and  it  is 
here  that  the  greatest  dej3th  of  rain  is  invariably  found.  The  difference  in  the  annual 
quantity  between  places  contiguous  to  each  other  and  in  the  same  valley,  is  often 
remarkably  great.  The  amount  increases  rapidly  as  we  recede  from  the  sea,  and 
towards  the  head  of  the  valley  the  incremental  ratio  is  enormous. 

Loweswater,  Buttermere  and  Gatesgarth,  in  the  same  line  of  valley,  are  about  two 
miles  apart  from  each  other;  yet  in  1848  Loweswater  has  received  76  inches.  Butter- 
mere  98  inches,  and  Gatesgarth  \ 33^  inches  of  water.  Here  in  a space  of  four  miles, 
we  have  a difference  of  57  inches  in  twelve  months,  and  in  some  years  the  propor- 
tional excess  is  still  greater.  The  head  of  Eskdale  receives  fully  one-fourth  more  rain 
than  the  middle  of  the  valley,  and  a like  difference  obtains  between  two  stations  in 
the  Vale  of  Borrowdale  about  a mile  apart,  whilst  the  proportion  between  the  deposit 
at  Ennerdale  Lake  and  a farm-house  three  miles  to  the  westward,  is  as  two  to  one 
nearly. 

At  an  early  stage  of  this  inquiry,  1 was  forcibly  struck  wdth  the  rapid  increment  in 
the  fall  towards  the  head  or  terminal  point  of  all  valleys,  and  I made  some  expe- 
riments in  order  to  ascertain  whether  the  effect  was  appreciable  at  much  shorter 
distances  than  any  of  those  just  referred  to.  For  this  purpose  I caused  a duplicate 
gauge  to  be  made,  in  all  respects  exactly  similar  to  the  one  at  Wastdale  Head,  and 
fixed  it  about  200  yards  higher  up  the  valley.  The  two  gauges  were  read  off  daily 
at  the  same  hour  for  twelve  months,  and  the  following  are  the  results : — 

Wastdale  Head. 


1845. 

No.  1. 

No.  2. 

Difference. 

in. 

in. 

in. 

October  

12-35 

11-89 

0-46 

November  

12-31 

11-90 

0-41 

December  

16-18 

15-78 

0-40 

1846. 

January  

12-97 

12-47 

0-50 

February  

6-60 

6-58 

0-02 

March 

10-35 

10-07 

0-28 

April  

6-59 

6-16 

0-43 

May  

3-65 

3-44 

0-21 

June  

5-33 

4-88 

0-45 

July  

16-82 

16-59 

0-23 

August  

8-96 

8-97 

-0-01 

September  

3-79 

3-64 

0-15 

Inches  

115-90 

112-37 

3-53 

It  will  be  observed  that  the  higher  gauge,  marked  No.  1,  is  always  in  excess,  and 
that  the  difference  in  a single  month  sometimes  amounts  to  half  an  inch,  though  the 
instruments  are  within  two  or  three  fields’  breadth  of  each  other.  Flere  the  effect  of 
a slight  increase  in  proximity  to  the  higher  mountains  is  very  apparent. 

Temperature. — The  mountain  valleys  are  commonly  supposed  to  be  intensely  cold, 
particularly  in  the  winter  season ; but  the  thermometer,  so  far  from  countenancing 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


325 


this  opinion,  shows  that  the  inhabitants  enjoy  a milder  and  more  equable  climate  than 
those  who  reside  in  the  open  country.  The  town  of  Whitehaven,  from  its  proximity 
to  the  sea  on  the  west  coast,  is  well  known  to  have  a much  higher  mean  temperature 
than  is  due  to  its  latitude ; it  is  also  much  less  subject  to  those  great  and  sudden 
fluctuations  of  heat  and  cold  to  which  inland  places  are  liable.  Yet  the  mean 
temperature  at  Seathwaite,  in  the  heart  of  the  lake  country,  is  only  about  1°‘5  lower 
than  with  us.  In  1847  and  1848  the  mean  temperature  of  Seathwaite  was  47°’46  and 
47°’ 10,  whilst  at  Kendal  it  was  46°‘67  and  46°'32  respectively. 

In  winter,  the  mean  of  the  night  temperature  is  several  degrees  higher  than  at 
Cockermouth  in  the  open  plain,  where  the  frost  is  much  more  severe.  The  indica- 
tions of  the  thermometer  are  in  accordance  both  with  the  assertions  of  the  residents 
and  with  my  own  observation  ; for  in  travelling  to  the  lakes,  where  the  roads  over  the 
commons  were  frozen  hard,  I have  often  found  them  quite  soft  and  clammy  on  arriving 
amongst  the  hills. 

These  valleys  not  only  have  a higher  winter  temperature  than  many  localities 
greatly  to  the  south  of  them,  but  they  very  rarely  experience  those  low  extremes 
which  not  unfrequently  occur  in  the  southern  counties  of  England.  The  mean 
temperature  of  the  winter  months  at  Chiswick,  in  Middlesex,  is  nearly  the  same  as 
in  the  Lake  District,  whilst  a much  greater  extreme  of  cold  is  frequently  felt  there 
than  in  the  north.  In  the  neighbourhood  of  the  metropolis  the  thermometer  some- 
times indicates  a degree  of  cold  almost  unknown  in  these  districts.  Thus,  on  the 
night  between  the  IJth  and  12th  of  February  1847,  the  temperature  at  Greenwich 
fell  to  6°,  at  Chiswick  to  4°,  and  at  Uckfield,  Sussex,  to  1°  ; when  at  Seathwaite  the 
minimum  was  24°'5,  and  the  minimum  for  the  month  20°. 

The  lakes,  by  absorbing  heat  in  the  summer  and  giving  it  out  in  the  winter 
months,  added  to  that  radiated  from  the  rocky  mountain  breasts,  and,  above  all,  the 
caloric  evolved  in  a sensible  form  by  the  condensation  of  such  enormous  volumes  of 
vapour,  no  doubt  tend  greatly  to  modify  the  climate  of  these  sequestered  localities. 

Temperature  on  Sea  Fell. — Last  summer  I stationed  a pair  of  Rutherford’s  self- 
registering thermometers  (previously  compared  with  a standard)  on  the  top  of  Sea 
Fell  Pike  ; they  are  suspended  in  a deal  box,  having  the  sides  and  base  riddled  with 
small  circular  holes,  so  that  the  instruments  are  freely  exposed  to  the  air,  and  at  the 
same  time  thoroughly  protected  from  the  effects  of  terrestrial  radiation.  On  the 
summit  of  the  Pike  is  a cairn,  or  large  pile  of  stones  about  8 feet  in  height,  having  a 
stout  pole  in  the  centre,  which  projects  about  2 feet  above  tbe  top  of  the  pile.  To 
this  pole  the  box  containing  the  thermometers  is  firmly  fixed. 

From  the  maximum  thermometer  I have  never  been  able  to  obtain  any  correct 
readings,  as,  from  some  cause,  the  steel  needle  is  always  found  at  the  extreme  end  of 
the  stem,  furthest  from  the  bulb.  I cannot  account  for  this,  unless  indeed  the  fine 
steel  needle  is  affected  by  electrical  currents  at  such  an  extreme  height  in  the  clouds. 
The  readings  of  the  maximum  thermometer  would,  however,  have  probably  been  of 

MDCCCXLIX.  2 u 


326 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


little  value,  as  it  would  be  almost  impossible  to  protect  it  from  the  eifect  of  solar, 
radiation. 

The  following  are  the  readings  of  the  minimum  thermometer  for  each  month  from 
July  to  the  end  of  the  year  1848  : — 

July,  22°;  August,  24°;  September,  18°;  October,  —6°;  November,  —6°;  De- 
cember, — 9°,  or  41°  below  the  freezing-point  of  water*. 

The  lowest  extreme  in  these  months,  in  the  Vale  of  Borrowdale,  at  4 feet  above  the 
ground,  was  as  under : — 

July,  45°;  August,  41°'5  ; September,  38°'5  ; October,  29°'5  ; November,  24°; 
December,  26°. 

The  Mountain  Gauges, — The  results  are  in  strict  accordance  with  those  of  the  two 
previous  years,  and  confirm  the  correctness  of  the  conclusion  drawn  from  them  in  a 
former  paper,  “ that  the  quantity  of  rain  increases  from  the  valley  upwards  to  an 
altitude  of  about  2000  feet,  above  which  it  begins  to  diminish.” 

'riius,  in  thirteen  months, — Inches. 

The  Valley  . . . 160  feet  above  sea,  has  received  127'47 

Stye  Head  . . . 1290  feet  above  sea,  has  received  138’72 

Seatollar  Common  1334  feet  above  sea,  has  received  139'48 

Sparkling  Tarn  . 1900  feet  above  sea,  has  received  148'59 

Great  Gabel  . . 2925  feet  above  sea,  has  received  9T32 

I regret  to  state  that  the  whole  quantity  of  water  collected  in  the  Sea  Fell  gauge 
during  the  winter  of  1847-48  was  lost,  in  consequence  of  injury  caused  by  the  frost. 
In  the  spring  of  last  year  I had  a new  set  of  receivers  constructed  for  these  stations, 
which  are  made  of  very  heavy  sheet  copper,  double-lapped  at  the  seams,  and  with  the 
bottoms  convex  inwards,  to  enable  them  the  better  to  bear  the  expansive  force  of  the 
water  during  its  conversion  into  ice;  so  that  a similar  accident  is  not  likely  to 
occur  again. 

From  the  table  for  the  summer  months,  it  appears  that  between  the  1st  of  May  and 
the  31st  of  October,  the  gauge  at  1290  feet  has  received  20^  percent,  more  rain  than 
the  valley;  at  1334  feet,  15^  per  cent,  more;  at  1900  feet,  41^  per  cent,  more;  at 
2928  feet,  6 per  cent,  less-,  and  at  3166  feet,  about  1 per  cent,  less  than  tlie  valley. 
The  excess  over  the  valley  is  somewhat  greater  at  all  the  stations  than  in  the  two 
previous  years,  and  Sea  Fell,  which  usually  obtains  less  rain  than  Gabel,  has  this 
summer  received  more. 

By  referring  to  the  table  for  the  winter  months,  we  find  that  the  station  at  1290 
feet  has  obtained  0’5  per  cent,  more  rain  than  the  valley;  at  1334  feet,  5^  per  cent. 

* On  the  29th  and  31st  of  January  1849,  the  box  containing  the  thermometers  was  so  thickly  encased  in 
ice,  that  it  could  not  be  opened.  The  minimum  temperature  for  the  month  was  read  off  on  the  12th  of 
February,  being  no  less  than  34°  below  the  zero  point  of  Fahrenheit’s  scale.  This  unheard-of  extreme  of 
cold  undoubtedly  occurred  on  the  night  between  the  2nd  and  3rd  of  January,  when  a naked  thermometer 
on  grass,  at  Whitehaven,  fell  to  -f-4°,  and  one  on  raw  wool  to  — 2°’8. — J.  F.  M. 


DISTRICT  OF  CUMBERLAND  AND  WESTMORELAND. 


327 


more ; at  1900  feet,  1^  per  cent,  more ; and  at  2928  feet,  42^  per  cent,  less  than  the 
valley.  Here  the  gauge  at  1334  feet,  which  on  the  average  of  the  two  preceding 
winters  received  the  same  quantity  as  the  Vale  of  Wastdale,  has  obtained  per 
cent,  more,  whilst  the  proportions  indicated  by  all  the  other  gauges  are  less  than  in 
1846  and  1847. 

It  will  also  be  observed  that  the  stations  at  1290  and  1334  feet,  which  in  summer 
receive  much  less  rain  than  at  1900  feet,  in  the  winter  months  receive  more.  This 
deficiency  is  obviously  owing  to  the  greater  proportion  of  snow  deposited  at  and  lost 
to  the  instrument  at  the  higher  station. 

Now,  as  in  the  winter  months  the  mountain  gauges  give  no  indication  of  a large 
proportion  of  the  fall  of  snovv,  all  of  which  is  secured  to  the  valley  stations  by  their 
being  daily  examined,  in  order  to  show  fairly  the  gradation  from  the  valley  upwards, 
we  must  exclude  those  months,  and  take  in  as  elements  in  the  calculation,  the  sum- 
mer months  only. 

Annexed  are  the  receipts  of  the  mountain  gauges  and  those  of  the  adjacent  valleys. 


during  the  summer  of  1848  : — 

inches. 

Stye  Head,  1290  feet  above  the  sea 60‘35 

Seatollar  Common,  1334  feet  above  the  sea 57‘97 

Sparkling  Tarn,  1900  feet  above  the  sea 70‘95 

Great  Gabel,  2925  feet  above  the  sea 46  81 

Sea  Fell  Pike,  3166  feet  above  the  sea 49'46 

Wastdale,  the  nearest  valley 50’ 16 

Eskdale  Head,  valley  to  the  S.S.E.,  3^  miles  distant  . . 37‘69 

Eskdale,  centre  of  valley  to  the  S.S.E.,  5^  miles  distant  . 32*46 

Ennerdale,  valley  to  the  N.W.,  3f  miles  distant  ....  42*96 

Loweswater,  valley  to  the  N.N.W.,  7i  miles  distant  . . 34*52 

Butterrnere,  valley  to  the  N.N.W.,  4^  miles  distant . . . 44*57 

Gatesgarth,  valley  to  the  N,,  2^  miles  distant .....  57‘66 


It  will  be  perceived  that  the  increase  in  the  warmer  months  up  to  2000  feet,  is 
great  and  rapid ; and  even  at  the  highest  attainable  elevation  in  England,  the  quan- 
tity of  rain  in  those  months  which  are  free  from  snow,  considerably  exceeds  the 
deposit  in  most  of  the  circumjacent  valleys.  Indeed  (Langdale  and  Seathwaite  ex- 
cepted) Gatesgarth  is  the  only  place  which  materially  exceeds  Sea  Fell  and  Gabel  in 
quantity ; but  as  Langdale  Head  is  ten  miles  distant,  and  as  Seathwaite,  besides 
being  several  miles  to  the  northward,  exceeds  enormously  the  wettest  of  the  other 
valleys,  it  is  obvious  that  it  would  not  be  fair  to  institute  a comparison  between  them. 
If  the  whole  of  the  snow  which  falls  at  the  mountain  stations  could  be  secured,  or 
an  exact  equivalent  in  water  be  allowed  for  it,  there  can  be  no  doubt  that  the  annual 
results  would  be  similar  to  those  for  the  summer  months  only  ; but  in  consequence  of 
the  greater  proximity  of  the  clouds  to  the  earth  in  the  winter  months,  the  proportions 
with  respect  to  the  valley  would  probably  be  somewhat  less. 

2 u 2 


MR.  J.  F.  MILLER  ON  THE  METEOROLOGY  OF  THE  LAKE 


Of  late,  I have  always  carried  with  me  a hygrometer  of  known  accuracy  on  visit- 
ing the  Lake  Districts,  and  all  experiments  which  1 have  made  on  the  hygrometrical 
state  of  the  atmosphere  at  considerable  altitudes  above  the  sea.  tend  to  establish  the 
law  which  this  investigation  has  brought  to  light,  by  showing  that  the  degree  of 
humidity  increases  upwards  from  tlie  earth’s  surface,  and  that  the  condition,  or  com- 
bination of  conditions  most  favourable  for  the  condensation  and  precipitation  of 
vapour  in  the  greatest  abundance,  does  obtain  somewhere  about  2000  feet  above  the 
sea  level. 

It  is  probable  that  the  atmosphere  is  generally,  at  or  near  the  point  of  saturation, 
at  and  above  2000  feet;  but  as  the  air  temperature  decreases  with  every  further  in- 
crease of  elevation,  its  capacity  for  vapour  is  proportionately  diminished,  and  con- 
sequently there  will  be  less  to  precipitate  than  at  the  point  where  the  temperature  of 
the  air  and  that  of  the  dew-point  first  begin  to  balance  each  other. 

From  the  nature  of  the  research,  it  is  quite  impossible  to  obtain  regular  and  con- 
nected observations  on  the  hygroscopic  state  of  the  atmosphere  at  such  great  heights, 
but  in  course  of  time  I hope  to  bring  together  a sufficient  number  of  data  to  enable 
us  to  connect  together  some  of  those  links  in  the  great  chain  of  causation  which 
regulates  the  gradation  and  amount  of  precipitation  at  various  altitudes  above  the 
earth’s  surface. 

I am  fully  aware  that  the  physical  law  indicated  by  these  results,  is  at  variance 
with  the  experiments  of  many  careful  observers,  and  with  the  inferences  drawn  from 
them  by  scientific  men  of  the  highest  standing.  But,  with  every  deference  to  the 
opinions  and  deductions  of  these  eminent  authorities,  it  must  be  admitted  that  they 
have  been  arrived  at  from  somewhat  scanty  materials.  So  far  as  my  knowledge  ex- 
tends, no  investigation  of  any  extent  or  continuity  had  been  made  in  this  department 
of  meteorology  previously  to  that  set  on  foot  in  the  Lake  District,  about  three  years 
ago.  The  facts  previously  on  record,  with  few  exceptions,  referred  to  comparatively 
moderate  altitudes,  mostly  under  1000  feet,  and  as  some  of  the  experiments  were 
made  on  the  mountain  breasts,  the  results  would  vary  greatly,  according  to  the  gra- 
dient and  position  of  the  acclivity,  and  as  the  gauges  were  placed  either  on  the 
windward  or  leeward  side  of  the  hill ; regard  must  also  be  paid  to  the  season  of  the 
year,  for  a gauge  which  in  summer  receives  considerably  more  rain  than  the  valley, 
may  in  winter  obtain  less ; and  where  the  instruments  are  read  off*  at  long  intervals, 
there  will  be  no  inconsiderable  loss  from  evaporation.  Moreover,  experience  con- 
vinces me  that  little  dependence  can  be  placed  on  the  results  obtained  from  gauges 
stationed  on  the  side  of  a hill,  with  whatever  care  they  may  have  been  secured.  For 
there  cannot  be  a doubt,  that  a pluviometer  placed  on  the  breast  of  a mountain,  even 
on  the  windward  side,  will  receive  much  less  rain  than  it  would  do  if  stationed  on  a 
hill-top  of  equal  elevation. 

Thus,  the  gauge  at  Brant  Rigg  in  Wastdale,  about  500  feet  above  the  sea,  though 
on  a comparative  flat,  but  with  abruptly  rising  ground  behind  it,  in  the  summer  of 


DISTRICT  OF  CUxMBERLAND  AND  WESTMORELAND. 


329 


last  year  has  not  only  received  less  rain  than  the  valley,  but  a smaller  quantity  by 
6 inches  than  at  3166  feet  on  Sea  Fell  Pike. 

At  a future  time  I hope  to  follow  out  this  inquiry  more  fully  and  systematically, 
by  placing  pluviometers  at  different  heights  on  the  breast  of  Sea  Fell,  with  the  view 
of  ascertaining  the  effect  produced  by  position  on  rising  ground,  over  or  under  that 
due  to  the  respective  elevations. 

It  is  not  pretended  that  the  law  which  appears  to  regulate  the  distribution  of  rain 
in  the  mountain  district  of  Cumberland,  will  equally  apply  to  every  similar  locality ; 
it  will  doubtless  be  variously  modified  according  to  latitude,  position,  and  many  other 
circumstances ; in  some  situations  all  trace  of  the  law  may  disappear,  and  in  others 
it  is  possible  that  it  may  be  reversed. 

As  my  sole  object  in  this  inquiry  is  a search  after  truth,  should  my  inferences  and 
deductions  be  found  to  be  incorrect  by  any  one  who  may  investigate  the  subject  more 
fully  and  successfully  in  another  locality,  I shall  feel  no  hesitation  in  acknowledging 
the  error. 

In  addition  to  the  chief  objects  of  research,  I record  the  particulars  of  all 
extraordinary  phenomena,  such  as  thunder  and  hail-storms,  great  floods,  and  parti- 
cularly whirlwinds  (to  which  the  district  is  very  liable),  with  a distant  prospect  of 
combining  the  whole  in  a separate  paper,  treating  of  the  physical  geography  of  the 
Lake  Country. 


Whitehaven^  February  6,  1849. 


tr'F.  T , ■ " h- . * ' 


' ; 


k’’’  ■ 


< '■ 


m 


•c^r 
•fH*.' 


'V  f, 


'i' ; 


<r.*‘ 


v<.!  ■.f  r'/."M'  '1. 


-,y:ilti»  lib  in^1.:.  ,,%i.,i'-  »«*r  - .. 

,t  , - v- urr  t»vr-^  . . 

.”'1!  ’■  (itiny  ' '■:i' ' Jis'ihi. 

I ■■■^  ■ I'  r ^ Ilf 

•,  ,..  ‘Vv;,: 

|■'‘4:  'X■  :\oi  -i}  f;  'i  '.'^t  •'■:■■  -•  *■■  WS#a5*:  j»<,'  > ‘- 

■•  »•■■''  ,' • ':■  ; *<  V . • . • ' .i.A,  1-1 


"m/ 

--r » 


' '■'"  “*■’•  i'"  ^Wv.h'vi’iuriO  v>  ;\/-'iy'  i - ‘ ■ ’ 

■ , ,,  ’ i’,;  ,';'.ir )!-.v.v  wNn>y  ;•  '•:■■ . 

: -•;  \ ,gstv„4«5^V^ 

'■' ' ' ' ''  ' "i  '.  f .•  ' , ■'■■5^  , ■ . , ' ' -:‘!s 

- ’l-;-vi'  .■:  '’juV-.!  Uk;,i  y '■-'?■ I yi||b»^P'  ' ''■''■\A''  ■■’'■  ''A  ':.  ' 

- f,i;’  ■ , , '.:  t ..Ji,  i>«fc 


i 'j’l'jiii'’’ *■’**-'  ■'■• ' ‘ .'.''•'n 

•• y 1 ::•  ' iU; i; .'» ; *''4  i‘'-'4  :=■’ fS'! 


• ■ ■■  ,.T^  »-.i..  ;„r  i,...-,  'f-'  '<  ■ _,. 


■'iR*^""  . v-_'t 

y H"  ‘'L'^ 

M 


v^<v  ■ ' ■ ' . 

Vy  •jftH'lHl’'  '.  ''■  -’V* >■'  ' ; V 

- ■r  ' y^  «■■'  ■■ 


A . ‘''i' ' ’•ili'KMil' 


[ 331  ] 


XVIII.  Description  of  an  Infusory  Animalcule  allied  to  the  Genus  Notommata  of 
Ehrenberg,  hitherto  undescrihed.  By  John  Dalrymple,  FAi.C  S. 

Communicated  hy  Thomas  Bell,  Sec.  K.S. 

Received  December  3,  1848, — Read  February  15  and  22,  1849. 

The  animalcule  I propose  to  describe  in  the  present  memoir  bears  so  close  a f 

resemblance  to  Notommata  Syrinx  of  Ehrenberg,  that  were  there  not  special  dif- 
ferences in  its  internal  anatomy,  such  as  I believe  could  not  have  been  overlooked  i 

by  that  great  observer,  one  might  almost  believe  it  to  be  the  same  animal. 

The  character  of  the  genus  is  thus  given  by  the  Professor  in  the  great  folio  of  j 

1838: — “Animal  ex  Hydatinaeorum  familia,  ocello  unico  occipitali,  pede  hisulco, 
caudam  furcatam  referente ; et  organo  rotatorio,  simpliciter  ciliato,  instructum.” 

These  characteristics  are  mostly  taken  from  its  external  organs  ; but  we  find,  on 
reference  to  the  description  of  the  animal,  that  it  possesses  an  intestinal  tube  termi- 
nating in  a cloaca  or  anal  orifice,  which  appears  from  the  plates  to  be  situated  at  the  i 

point  where  the  foot  or  forcipated  tail  emerges.  The  grand  structural  difference, 
then,  to  be  remarked  in  the  animalcule  that  forms  the  subject  of  the  following  pages, 
is  that  there  exists  no  intestine,  and  therefore  no  anal  orifice,  nor  any  tail  or  forci-  j 

pated  extremity.  This  want  of  intestine  removes  it  into  a lower  position,  as  regards 
animal  life,  and  I would  therefore  refer  it  to  a subgenus  of  Notommata,  if  it  be  even 
entitled  to  a place  so  high  in  the  scale  of  Infusoria. 

In  shape  it  resembles  a flask  or  bell-flower  (corpore  campanulato)  (Plate  XXXIII. 
fig.  1),  narrower  towards  the  head  and  expanded  below,  of  such  extreme  transparency  j 

as  to  permit  all  the  internal  organs  to  be  clearly  visible,  even  to  the  contents  of  the  jj 

stomach. 

’ I 

It  moves  slowly  and  equably,  describing,  while  feeding,  narrow  circles  in  the 
water,  so  as  seldom  to  be  far  out  of  the  field  of  an  half-inch  object-glass  ; but  when  i 

disturbed  it  will  go  off  in  a direct  line  until  it  again  becomes  quiet,  or  resumes  its  j 

former  slow  circular  motion.  It  is  visible  to  the  unassisted  eye  as  a minute  semi-  ' 

transparent  spot,  and  is  readily  drawn  into  a glass  tube  when  it  is  desired  to  select 
one  for  examination.  Its  average  length  is  rather  less  than  half  a line,  and  at  its  ! 

I broadest  part  about  the  fifth  of  a line  in  breadth.  ['j 

1 In  order  to  convey  a correct  idea  of  its  anatomy,  it  will  be  desirable  to  describe,  {i 

I first,  its  general  appearance  and  the  grouping  of  the  organs,  and  subsequently  to  j| 

j take  the  latter  under  the  heads  of  the  assimilative  and  reproductive  functions. 

It  has  already  been  said  that  in  shape  this  animalcule  resembles  a bell-flower,  or 
I Iti 


332 


MR.  j.  i)alrymple;’s  description  of  an  infusory 


flask,  pellucid  in  the  highest  degree,  possessing  no  colour  except  what  is  due  to  a 
small  pink  eye  and  to  the  stomach,  which  varies  in  hue  according  to  the  food,  but 
generally  of  a yellowish  brown  hue.  When  seen  laterally,  or  in  profile  (if  one  may 
so  say),  the  lower  part  is  not  equally  convex,  for  it  slopes  off  from  one  side,  so  that 
the  most  inferior  part  of  the  outer  case  is  somewhat  oblique,  and  one  side  somewhat 
longer  than  the  other.  It  is  towards  the  inferior  part  of  this  longer  side  that  an  open- 
ing (Plate  XXXIII.  fig.  1 S),  valvularly  closed,  is  observed  in  profile,  which,  when  seen 
in  front,  is  represented  by  a semilunar  slit  (Plate  XXXIII.  fig.  2 H),  whose  concavity  is 
turned  downwards ; this  is  the  vaginal  aperture,  whence  the  embryo,  when  mature, 
or  the  ova,  are  expelled.  Each  leaf  of  this  valve  is  provided  with  special  muscles 
for  opening  it,  while  it  appears  to  be  kept  closed  partly  by  its  own  elasticity,  and 
partly  by  the  pressure  of  the  fluid  contained  in  the  body  of  the  animalcule.  Upon 
tlie  hyaline  tegument  of  the  body  may  be  seen,  faintly  indicated,  transverse  or  cir- 
cular bands  or  rings  (Plate  XXXIII.  fig.  1 R)  that  mark  the  points  where  folds  are 
developed  upon  muscular  contractions  of  the  animal,  and  it  is  on  the  inner  side  of 
this  tegumentary  covering,  at  the  place  where  the  rings  are  seen,  that  the  long, 
ribbon-shaped  muscles  are  symmetrically  attached  (PlatC'XXXIII.  fig.  1 M). 

The  principal  movements  of  progression  are  effected  by  means  of  the  ciliary  or 
rotatory  apparatus,  at  the  head  or  superior  extremity  of  the  body,  and  which  seem 
to  be  independent  of  the  more  special  rotatory  mechanism,  whereby  two  currents  are 
produced  in  the  water,  that  draw  within  their  influence  the  smaller  animals  that 
serve  as  food : on  reaching  the  point  where  the  two  opposite  moving  vortices  meet, 
the  food  is  immediately  directed  backwards  in  a straight  line  intermediate  between 
the  two,  and  so  enters  the  oral  orifice  of  the  animal  (Plate  XXXIII.  fig.  1 B).  There 
seems  however  to  be  a distinct  power  of  selection,  for  the  slightest  lateral  movement 
of  the  head  of  the  animal  enables  it  to  avoid  objects  too  large  for  admission,  or  which 
it  wishes  to  reject. 

The  cilia,  by  which  all  these  motions  are  effected,  appear  to  be  placed  upon  raised 
eminences  or  processes,  rising  at  regular  intervals  from  the  upper  circlet  or  coronet  of 
the  animal  (Plate  XXXIII.  fig.  1 A);  and  when  the  power  is  feeble  from  exhaustion,  the 
lashing  movements  of  the  cilia  are  very  visible.  Immediately  below  the  oral  orifice 
is  a considerable  dilatation,  closed  above  by  the  union  of  three  portions  of  firm  inte- 
gument, forming  as  it  were  a labial  apparatus,  or  at  least  a mechanism  for  closing  the 
mouth,  which  resembles  very  closely  the  visor  which  conceals  the  powerful  jaws  of  the 
larvae  of  the  Libellulse.  Within  the  mouth  are  situated  a powerful  pair  of  forcipated 
jaws  (Plate  XXXIII.  fig.  1 E)  which  seize  the  prey,  and  if  large  comminute  and  break  it 
down.  Eacl)  ramus  of  the  jaw  is  jointed  (Plate  XXXIII.  fig.  3)  on  a short  arm,  which 
is  again  moveable  upon  a central  axis  prolonged  posteriorly;  and  each  short  arm  has  a 
curved  and  strong  process,  to  which  the  very  powerful  and  somewhat  complicated 
muscles  are  attached.  The  forcipated  extremities  of  the  jaws  are  bifid,  and  may  be 
fairly  designated  teeth,  one  being  sharp  and  hooked,  the  other  flat  or  chisel-edged. 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


333 


for  the  purpose  of  comminution.  A third  sharp  and  curved  tooth  is  observed  on  the 
centre  of  the  long  arm  of  the  jaw.  I have  thought  also  to  have  observed  a second 
much  more  slender  and  pointed  pair  of  jaws  (Plate  XXXIII.  fig.  3 H),  but  this  requires 
confirmation.  When  a small  animalcule  is  seized,  a Gonium  for  instance,  on  which  it 
feeds  greedily,  it  is  placed  as  it  were  on  a firm  cushion  in  front  of,  and  somewhat 
below,  the  jaws,  and  is  thus  prevented  from  escaping  beyond  the  action  of  the  teeth. 
Opposite  the  jaws  appears  the  red  eye,  of  which  a further  description  will  be  given 
presently. 

Below  the  mandibular  apparatus  the  tissues  expand  into  a sort  of  membranous 
pharyngeal  cavity  (Plate  XXXIII.  fig.  1 F),  terminating  below  in  a funnel-like  apex, 
leading  to  the  oesophagus  (Plate  XXXIII.  fig.  1 G).  The  pharynx  is  very  contractile, 
and  furnished  accordingly  with  a muscular  tissue. 

The  oesophagus  is  narrow,  and,  while  not  in  the  act  of  giving  passage  to  the  food, 
is  closely  contracted  ; when,  however,  a morsel  is  about  to  be  transferred  from  the 
pharynx  to  the  stomach,  the  latter  organ  is  brought  up  by  special  muscles  to  within  a 
short  distance  of  the  former,  and  the  transfer  quickly  takes  place  down  the  now  dilated 
oesophagus ; and  if  the  prey  be  of  considerable  size,  it  is  even  forced  downwards  by 
the  strong  action  of  the  united  jaws. 

Immediately  before  the  junction  of  the  oesophagus  with  the  stomach,  two  kidney- 
shaped glands  (Plate  XXXIII.  fig.  1 H)  are  seen  attached,  one  before  and  one  behind  this 
tube.  The  glands  seem  composed  of  nucleated  cells,  imbedded  in  a granular  stroma ; 
and  in  the  concavity  of  the  kidney-shaped  organ  may  be  seen  a definitely-shaped 
granular  mass  leading  to  the  duct,  conveying  the  secretion  to  the  stomach,  which  it 
enters  just  above,  or  by  the  side  of  the  insertion  of  the  oesophagus.  These  glands  are 
evidently  salivary  or  pancreatic,  and  at  least  are  subservient  to  the  process  of  digestion. 

The  stomach  (Plate  XXXIII.  fig.  1 I)  itself  is  a comparatively  large  and  sacculated 
cavity,  of  an  ovoid  shape,  the  sacculi  giving  it  somewhat  the  aspect  of  a bunch  of  grapes 
where  the  berries  are  closely  compacted  together.  Each  little  pouch  or  sacculus  has 
in  its  centre  a large  clear  nucleus ; and  on  comparing  it  with  the  stomach  of  Notom- 
mata  claviculata  (Ehren.),  in  which  hepatic  caeca  are  appended  to  each  sacculus, 
there  is  reason  to  think  these  nucleated  cells  also  subserve  the  function  of  a liver. 
This  belief  is  further  countenanced  by  the  fact  of  the  stomach,  when  employed  in  the 
digestion  of  the  food,  assuming  a yellowish  brown  colour,  and  at  least  the  whole  pro- 
cess of  assimilation  is  performed  in  this  cavity  alone.  There  is  no  other  orifice  to 
the  stomach  except  the  cardiac  or  oesophageal  one ; hence  there  is  no  intestine,  and 
the  siliceous  shells  of  its  prey,  and  other  rejectamenta,  are  brought  back  to  the  pha- 
rynx and  rejected  by  the  oral  orifice.  In  this  process  also  we  see  the  forcipated 
jaws  frequently  assisting  to  eject  the  larger  portions  of  the  digested  food.  I have 
frequently  seen  this  act  performed,  and  the  empty  shells  of  Brachioni  and  Closteria 
returned  and  forced  out  again  by  the  action  of  the  jaws.  There  are  apparently  long 
ribbon-shaped  muscles  (Plate  XXXIII.fig.G)  that  pass  from  the  pharynx  along  the  oeso- 

2 x 


MDCCCXLIX. 


334 


MR.  J.  DiiLRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 


phagus  and  embrace  on  many  sides  the  stomach  to  its  very  fundus,  where  they  meet, 
and  interlace.  These  muscles  not  only  approximate  the  stomach  to  the  pharynx, 
but  compress  it  also,  enabling  it  to  discharge  the  debris  of  the  food.  Two  Or  three 
fine  filamentous  muscles  are  attached  to  the  fundus  and  fixed  to  the  lowest  part  of 
the  tegumentary  case  of  the  animal,  serving  to  retract  the  stomach  again  when  it 
has  discharged  its  contents.  The  principal  food  appears  to  be  species  of  Gonium,  and 
other  small  infusoria;  but  also  at  times  it  will  swallow  hard  and  thorny  Brachioni, 
and  even  the  young  of  its  own  species.  The  total  absence  of  all  intestinal  canal 
separates  this  animal  from  Notom mata,  which  has  a distinct  gut  and  cloaca,  as  is 
well  observed  in  the  N.  claviculata ; and  if  development  of  digestive  apparatus  be 
taken  as  a distinctive  character,  it  removes  this  form  to  a lower  grade  than  any  roti- 
ferous  animal  I am  yet  acquainted  with. 

As  it  is  clear  that  the  growth  and  nutrition  of  the  animal  must  proceed  from  the 
digestion  of  appropriate  food,  and  as  there  is  no  true  vascular  system,  it  follows  that 
the  assimilated  fluid  must  permeate  the  parietes  of  the  stomach  and  enter  the 
general  or  peritoneal  cavity  of  the  animal,  which,  however  transparent  the  whole  of 
the  body  appears  to  be,  must  be  filled  with  this  colourless  nutrient  fluid  or  blood. 

In  this  animal,  as  well  as  in  the  Notommata  figured  by  Ehrenberg,  there  is  a 
peculiar  organ,  which  in  the  explanation  of  figure  2 of  plate  49,  he  designates  “kie 
men”  or  gills,  and  as  “ kiernengefasse,”  “gill-vessels  thicker  than  the  gill,  for  which 
reason  the  tremulously  moving’  gill  cannot  be  a heart.” 

This  peculiar  organ  consists  in  a double  series  of  transparent  filaments  (Plate 
XXXIII.  fig.  1 K)  (for  there  is  no  proof  of  their  being  tubes  or  vessels)  arranged  from 
above  downwards  in  a curved  or  semicircular  form,  symmetrical  when  viewed  in  front ; 
or  when  seen  in  profile  (the  most  common  position  of  the  animal  under  the  microscope) 
as  two  series  of  filaments  whose  convexity  is  turned  towards  the  exterior  of  the  body. 
These  filaments  above  and  below  are  interlaced,  loop-like,  while  another  fine  filament 
(Plate  XXXIII.  fig.lL)  passes  in  a straight  line,  like  the  chord  of  an  arc,  uniting  the  two 
looped  extremities.  To  this  delicate  filament  are  attached  little  tags,  or  appendices, 
whose  free  extremities  are  directed  towards  the  interior  of  the  animal,  and  which  are 
observed  to  be  affected  by  a tremulous,  apparently  spiral  motion,  like  the  twisting  of 
a screw.  This  is  undoubtedly  due  to  cilia  arranged  round  these  minute  appendices. 

I’he  tags  (Plate  XXXIII.  fig.  7 B)  above  described  are  from  eight,  twelve,  or  even 
twenty  in  number,  varying  in  different  specimens,  though  always  present  in  greater  or 
less  numbers.  There  seems  to  be  much  obscurity  in  Ehrenberg’s  description,  and  he 
does  not  appear  to  be  quite  decided  as  to  their  proper  function  ; for  though  the  desig- 
nation of  kiemen  or  gills  would  infer  that  he  supposed  them  subservient  to  the 
purpose  of  respiration,  other  observers  have  suspected  them  to  belong  to  a cardiac 
system.  Now  it  does  not  appear  consistent  with  the  class  of  animals  to  which  these 
infusoria  belong,  to  expect  tubular  vessels  or  a heart,  but  nevertheless  I believe  the 
organs  in  question  to  be  a peculiar  circulating  system. 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


335 


I have  said  that  the  body  of  the  animal  is  filled  with  fluid,  most  probably  analo- 
gous to  blood,  while  the  ciliated  tags,  or  appendices,  in  perpetual  motion,  must 
produce  currents  in  this  fluid,  and  probably  in  an  uniform  and  determinate  direction. 
In  this  way  the  nutrient  plasma  will  be  brought  regularly  in  contact  with  all  parts  of 
the  interior  of  the  body,  and  the  process  of  nutrition  go  on  as  in  insects,  without  the 
intervention  of  tubular  vessels,  the  dorsal  heart  in  them  serving  only  to  give  direction 
and  circulation  to  the  blood.  I am  the  more  impressed  with  this  belief,  since  these 
filamentous  organs  are  in  close  approximation  with  a large  contractile  sac,  presently 
to  be  described,  which  probably  performs  a respiratory  function. 

As,  however,  this  is  a much-disputed  part  of  the  organization  of  the  family  of  Hy- 
datinese,  I shall  here  quote  Ehrenberg’s  own  observations  upon  Hydatina  Senta, 
which  he  takes  as  the  type  of  the  whole  family.  # 

“ It  happened  to  me  in  1832  to  obtain  a clear  view  of  the  vibratory  corpuscles 
which  CoRTi  in  1794  saw,  and  doubtingly  considered  to  be  four  hearts.  I found 
here  eight  of  these  bodies,  four  on  each  side  in  two  rows  affixed  to  the  sexual  glands. 
In  other  Rotifera  I saw  many  more  of  the  same  kind  ; and  in  Notommata  Syrinx  and 
claviculata,  a larger  vessel  was  attached  to  the  free  and  separated  glands.  These 
vibrating  corpuscles  are  small  and  pear-shaped,  free  at  one  extremity  and  attached  at 
the  other,  on  all  sides  like  little  shaking  purses,  which  either  have  on  them  a longer 
spiral  coil,  or  within  them  four  small  separate  vibrating  folds,  which  are  not  under 
the  volition  of  the  animal.  One  only  sees  them  clearly  when  the  animal  is  flattened 
by  the  superimposition  of  a very  thin  light  plate  of  glass,  not  crushing  them.  In 
Hydatina  these  vibrating  valves  or  folds  appear  to  be  placed  within  the  little  purses. 
In  Notommata  collaris  I have  lately  seen  something  prominent  on  their  edges,  and 
must  therefore  believe  these  folds  to  be  placed  on  the  outside.  Besides,  there  appears 
in  the  neck  of  Hydatina  to  be  present  an  opening  in  direct  and  important  connexion 
with  these  organs,  that  in  many  other  Rotifera  projects  as  a spur-shaped  horn.  Close 
round  this  opening  are  placed  the  nerve-loops  of  the  neck,  and  a nerve-ring  appears 
to  encircle  it  as  a ganglion. 

The  animalcule  appears  to  take  in,  and  expel  alternately,  clear  water  through 
this  opening  in  the  neck,  and  thus  each  vibrating  organ  throughout  may  be  an  internal 
gill  producing  respiration,  although  a circulation  of  the  nutrient  fluid  (safte),  partly 
on  account  of  the  extremely  small  diameters  of  the  vessels,  and  partly  from  the 
transparency  and  minuteness  of  the  blood-corpuscles,  remains  as  yet  undiscovered, 
though  probably  not  deficient.  Many  of  the  older,  as  well  as  more  recent  observers, 
who  speak  of  a heart  in  Rotifera,  mistook  the  pharynx  for  this  organ.  Corti  took 
the  moving  jaws  and  gills  for  it ; moreover,  while  no  true  heart  has  been  discovered 
hitherto,  it  is  impossible  that  it  should  hereafter  be  found  to  exist,  especially  as  no 
congenerous  animalcules  have  one,  although  by  the  tremulous  motions  of  the  vascular 
partitions  {gefdsswande)  the  circulation  of  the  blood  is  carried  on.” — Ehrenberg, 
page  415,  fol.  edit.  1838. 


2x2 


336 


MR.  J.  DALRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 


Besides  this  development  of  his  views,  it  will  be  found  that  the  great  naturalist,  in 
the  explanation  of  the  plate  illustrating  the  anatomy  of  Hydatina  Senta,  believed  the 
cords  to  whieh  the  gills  or  vibratory  corpuscles  are  attaehed  to  be  male  organs, 
‘‘testiculi”  {mannliche  driisen)  ; a position  most  unlikely  for  the  location  of  respira- 
tory organs,  w’ere  they  even  probably  such.  As  it  will  be  proved  that  in  the  ani- 
malcule I am  describing  no  such  male  organ  exists  under  this  form,  and  that  another 
apparatus  appears  to  subserve  the  office  of  respiration,  it  is  far  more  probable  that 
they  are  part  of  the  mechanism  of  circulation,  and,  as  such,  secondary  to  the  function 
of  respiration. 

It  has  been  previously  stated  that  a valvular  opening  exists  in  the  inferior  part  of 
the  animal  that  gives  exit  to  the  matured  embryo  or  to  ova,  and  may  therefore,  from 
its  obvious  and  demonstrable  purpose,  be  denominated  the  vaginal  aperture.  This 
communicates  with  a membranous,  highly  extensible  and  very  contractile  ovisac 
(Plate  XXXIII.  fig.  1 P),  in  which  the  foetus  is  matured,  and  by  the  contractions  of 
which  it  is  finally  expelled  from  the  mother. 

Just  above  the  ovisac,  and  communicating  with  the  vaginal  canal,  is  a considerable 
transparent  sac  (Plate  XXXIII.  fig.  1 N),  which,  when  distended,  presents  a spherical 
shape.  It  is  exceedingly  delicate,  and  may  be  seen  to  contract  by  the  action  of  slender 
muscular  fibres  with  great  rapidity,  in  which  act  it  is  thrown  into  numerous  regular 
folds  or  pouches,  and  in  that  condition  appears  not  very  dissimilar  to  the  large  cellular 
lungs  of  Batrachia.  These  contractions  and  subsequent  dilatations  go  on  with  some 
approach  to  regularity,  and  I have  counted  from  six  to  eight  in  a minute  ; but  when  the 
animal  is  disturbed,  or  attempting  to  escape  from  the  pressure  of  the  “ live  cage,”  or  in 
the  act  of  expelling  an  embryo,  the  contractions  and  dilatations  of  the  sac  are  greatly 
and  irregularly  increased,  sometimes  to  twenty  in  the  minute.  It  is  on  the  outside 
and  over  this  sac  that  the  principal  ciliated  tags  of  the  circulatory  organ  are  placed. 
The  explanation  which  I venture  to  give  is,  that  this  sac  draws  in  the  water  in  which 
the  animal  lives,  and  expels  it  again  by  the  vaginal  orifice,  and  it  is  by  bringing  the 
blood  by  means  of  the  ciliary  movements  of  the  little  bodies  just  described  into  in- 
termediate contact  with  the  air  of  the  water,  the  fine  membrane  of  the  contractile  sac 
alone  intervening,  that  aeration  or  respiration  is  performed.  An  analogous  contrac- 
tile sac  may  be  seen  in  Rotifer  vulgaris,  situated  near  the  cloacal  orifice. 

At  first  sight  this  pulmonary  sac  (Plate  XXXIII.  fig.  7 C)  appears  to  be  an  appendage 
to  the  ovisac  (Plate  XXXIII.  fig.7  D),but  frequent  observation  of  the  female  in  all  stages 
of  gestation  convince  me  that  it  has  no  relation  to  the  generative  function.  The  same 
sac  is  described  by  Ehrenberg,  in  the  explanation  to  the  figure  of  Notommata  Myr- 
meleo,  as  a contractile  male  vesicle  with  evident  vascular  ramification.  The  position 
and  the  description  of  a contractile  bladder  show  that  the  learned  Professor  is  speak- 
ing of  the  same  organ  I have  described,  but  it  will  be  clearly  shown  by  and  by  that 
it  has  no  concern  with  sex,  while  the  vascular  ramifications  are  neither  more  nor  less 
than  the  muscular  fibrillee  by  which  the  contractions  are  effected. 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


337 


Every  animal,  however  low  in  the  scale  of  beings,  is  nourished  by  some  process  of 
converting  either  animal  or  vegetable  products  into  themselves ; but  when  we  observe 
such  elaborate  organs  of  alimentation  in  Notommata,  such  as  those  of  prehension, 
mastication,  deglutition  and  digestion,  we  may  infer  at  least  the  existence  of  some 
apparatus  that  may  suflSce  to  circulate  and  aerate  the  elaborated  fluid  or  blood.  A 
process  of  respiration  is  equally  important  to  these  beings  as  food  and  digestion,  for 
it  is  well  known  that  the  higher  forms  of  infusory  animals  will  not  exist  in  water 
either  deprived  of  air  or  in  which  the  air  has  been  consumed  by  long  inhabitation. 
The  contractions  of  the  vesicle  I have  described  resemble  very  closely  the  expirations 
of  a vesicular  lung,  and  in  some  forms  of  Rotifera  it  appears  almost  wholly  to  vanish 
when  contracted,  and  by  expansion  again  to  become  suddenly  apparent. 

With  regard  to  the  nervous  system,  traces  of  such  an  apparatus  may  be  distinctly 
recognised  in  the  optic  lobe  or  mass  of  ganglionic  matter,  on  the  centre  of  which  is 
placed  the  pink  pigmentous  matter  constituting  the  organ  of  vision  (Plate  XXXIII. 
fig.  1 C) ; from  this  nervous  mass  a fine  filament  may  be  observed  passing  obliquely 
down  the  body  of  the  animal,  attached  at  about  the  centre  of  the  outer  tegumentary 
case,  Plate  XXXIII.  fig.  1 T.  At  this  point  exist  two  small  tubercles,  around  which  are 
set  three  or  four  short  hairs,  cilia,  or  setse.  The  filament  connecting  these  tubercles 
with  the  optic  lobe,  is  enlarged  at  its  lower  part  by  the  addition  of  two  or  three 
small  ganglionic  globules  (Plate  XXXIII.  fig.  7 E),  and  appears  to  send  off*  delicate 
filaments  to  the  stomach,  salivary  glands,  ovaries  and  ovisac.  It  may  be  a question 
also  v/hether  the  curved  and  looped  fibres  connected  with  the  circulatory  organ  may 
not  have  ganglionic  corpuscles  intermingled  with  them. 

The  muscular  system  is  best  explained  by  reference  to  the  drawing,  Plate  XXXIII. 
fig.  8.  It  is  merely  necessary  to  remark  here,  that  besides  the  long  ribbon-shaped 
muscles  that  serve  to  contract  and  to  retract  the  head  and  body,  there  are  numerous 
muscular  filaments  having  their  fixed  points  in  the  integumentary  case,  and  inserted 
into  the  various  internal  organs  upon  which  they  act ; thus,  there  are  delicate  muscles 
attached  to  the  fundus  of  the  stomach  to  retract  it  into  its  situation  after  it  has  been 
drawn  up  to  the  pharynx  either  to  receive  or  reject  its  food. 

Other  muscles  are  fixed  to  the  ovaries ; and  a very  intricate  set  of  reticular  fibres 
are  expanded  over  both  the  respiratory  sac  and  ovisac,  producing  in  the  one  case  the 
strong  expiratory  contractions  of  this  vesicle,  and  in  the  other  the  expulsatory  action 
attending  the  birth  of  the  embryo. 

The  broad  ribbon-shaped  muscles  have  faint  indications  of  cross  markings,  as  seen 
in  the  voluntary  muscles  of  higher  animals,  and  in  young  specimens  have  frequently 
still  remaining  the  nuclei  of  the  cells  imbedded  in  the  fibre,  whence  this  tissue  has 
been  originally  developed. 

The  other  more  conspicuous  organs  visible  within  the  transparent  body  of  this 
animalcule  are  those  appropriated  to  the  reproduction  of  the  species,  and  are  very 
perfect  in  their  kind. 


338 


MR.  J.  DALRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 


It  may  be  stated,  in  limine,  that  it  is  now  certain  that  these  animals  are  divided 
into  female  and  male,  the  latter  being  one  of  the  most  curious  organisms  I am  ac- 
quainted with. 

As  however  the  general  description  has  hitherto  been  taken  from  the  female,  I shall 
describe  the  reproductive  organs  in  them  first. 

There  is  an  ovary,  ovisac,  expulsory  mechanism,  vaginal  canal  and  vulva. 

The  ovary  (Plate  XXXIII.  fig.  1 O)  consists  of  an  elongated  mass,  curved  into  the 
general  form  of  a horseshoe,  either  extremity  being  rounded  and  slightly  enlarged.  In 
texture  it  appears  gelatinous,  with  numerous  interspersed  granules,  forming  a stroma, 
in  which  are  imbedded  many  nucleated  cells  (Plate  XXXIII.  fig.  1)  that  afterwards 
become  ova.  The  ovary  is  larger  in  proportion  as  the  animal  is  young,  and  visibly 
shrinks  and  becomes  almost  atrophied  as  it  is  advanced  in  age  and  has  produced 
many  embryos.  This  ovary,  like  the  stomach,  is  very  moveable  in  the  general  cavity 
of  the  body,  but  in  the  newly-born  female,  before  many  movements  have  taken  place, 
and  especially  before  the  stomach  has  been  distended  with  food,  its  position  is  such 
that  the  two  horns  are  pointed  upwards,  and  the  digestive  sac  is  placed  within  the 
concavity  of  the  horseshoe  (Plate  XXXIII.  fig.  2 0 0):  thus  the  ovary  is  symmetrically 
placed,  and  appears  like  a double  organ  united  by  a broad  bridge  in  the  centre.  To 
either  horn  are  attached  slender  muscles  or  tegumentary  fibres  that  retain  it  in  its 
general  position,  although  either  producing  or  permitting  free  movements ; for  when 
the  ovisac  becomes  distended  with  one  or  more  embryos,  which  always  occupy  the 
lower  part  of  the  animal,  it,  as  well  as  the  stomach,  is  pushed  out  of  its  ordinary  or 
original  position. 

To  the  lower  part  of  the  ovary  appears,  connected  by  slight  muscular  or  ligament- 
ous fasciculi,  the  extremity  of  the  ovisac,  which,  if  unoccupied  by  an  embryo,  is  closely 
contracted,  and  appears  like  a wavy,  extremely  delicate  membrane.  The  female  is 
both  oviparous  and  ovo-viviparous,  the  latter  condition  being  the  one  most  frequently 
observed ; and  in  fine  hot  weather  it  is  not  unusual  to  find  females  with  four  or  five 
young  in  various  stages  of  development,  from  the  early  ovum  to  the  mature  embryo, 
ready  for  expulsion. 

The  extreme  transparency  of  the  animal  permits  the  ready  observation  of  all  stages 
of  development.  We  can  trace  the  germinal  vesicle,  surrounded  by  a gelatinous  and 
granular  mass  or  yelk,  and  enveloped  in  a delicate  chorion,  still  attached  to  the  ovary. 
The  germinal  vesicle  is  generally  very  distinct  and  excentric  (Plate  XXXIV.  fig.  2),  the 
whole  egg  being  an  ovoid  figure.  The  ovum  is  then  enveloped  by  the  open  end  of  the 
ovisac,  and  the  base  of  attachment  to  the  ovary  being  gradually  narrowed  to  a small 
peduncle,  it  finally  escapes  free  into  the  membranous  ovisac,  where  the  further  develop- 
ment is  carried  on.  We  then  shortly  observe  the  ovum  to  increase  in  size,  the  distinct 
and  dark  granulesappearing  to  become  surrounded  with  cell -walls,  and  the  gelatinous 
mass  is  converted  into  a large  number  of  distinct  nucleated  cells,  Plate  XXXIV.  fig.  3. 
I cannot  say  I have  traced  the  division  of  the  original  cell  into  two,  four,  eight,  &c.  in 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


339 


arithmetical  progression,  though  this  is  not  improbable,  since  in  an  early  ovum  I have 
once  observed  the  separation  into  two  distinct  portions,  in  each  of  which  there  wero 
several  large  granules  or  oil-globules,  Plate  XXXIV.  fig.  5". 

Each  granular  point,  however,  seems  subsequently  to  become  the  nucleus  of  a cell, 
round  which  the  wall  is  developed.  After  a short  time  the  numerous  cells  assume  a 
more  definite  arrangement  (Plate  XXXIV.  fig.  4),  and  are  grouped  together  in  masses, 
at  which  time,  from  the  slight  irregularities  in  their  contour,  the  fine  chorion  is  seen 
around  them,  forming  an  envelope  for  the  whole. 

By  and  by  the  groups  of  cells  become  more  distinct  masses,  and  a larger  collection 
of  them  at  one  end  of  the  ovum  (Plate  XXXIV.  fig.  5)  indicates  the  future  position  of 
the  head ; while  smaller  subdivisions  are  symmetrically  arranged  around  another 
group,  which  finally  becomes  the  stomach. 

Soon  after  this  period,  the  cells,  or  groups  of  them,  evidently  become  developed 
into  tissues,  and  the  embryo  begins  to  assume  a definite  shape,  and  the  outline  of  the 
tegumentary  covering  is  visible.  Presently  a slight  ciliary  movement  is  observed  at 
one  end,  indicating  the  head  of  the  animal,  and  the  chorion  shortly  after  bursting, 
the  embryo  becomes  free,  although  closely  surrounded  by  the  delicate  contractile 
membrane  of  the  ovisac. 

Having  arrived  at  this  epoch  (Plate  XXXIV.  fig.  10  A),  the  perfection  of  the  organs 
rapidly  takes  place,  and  we  begin  to  recognise  the  stomach,  salivary  glands,  ovary,  and 
the  ribbon-shaped  muscles  of  voluntary  motion ; in  these  latter  the  original  nucleus 
of  the  cell,  which  has  elongated  and  been  developed  into  muscular  tissue,  is  still 
plainly  visible,  imbedded,  as  it  were,  in  the  fibre.  The  embryo  has  now  voluntary 
motion,  for  while  rapid  ciliary  movements  are  constantly  going  on  around  the  head, 
the  animal  frequently  contracts  and  extends  its  body,  rolls  over,  or  changes  its  posi- 
tion in  the  ovisac.  The  jaws  may  now  be  seen,  and  are  not  unfrequently  moved  as 
if  exercising  or  trying  their  power.  The  red  eye  has  previously  been  visible,  and 
now  and  then  the  head  of  the  animal  is  so  placed  that  we  are  enabled  to  look  down 
upon  it,  and  observe  the  symmetrical  position  of  the  jaws  with  the  eye  placed  oppo- 
site to  the  entrance  of  the  mouth  and  pharynx,  a position  it  is  difficult  to  meet  with 
for  any  continued  period  in  the  adult,  from  its  instability  and  frequent  movements 
under  the  glass. 

The  embryo  may  now  be  said  to  be  ready  to  quit  the  parent,  but  some  time  pre- 
vious to  its  exit  it  is  seen  exercising  various  and  energetic  movements,  attempting  as 
it  were  to  escape ; but  until  the  valvular  opening  of  the  vagina  is  opened  or  retracted 
by  special  muscles,  the  forward  movements  of  the  foetus  only  press  the  valve  closer 
down,  and  shuts  it  more  firmly  against  the  side. 

At  length,  after  one  or  two  partial  openings  of  the  valve,  the  muscles  withdraw  it 
completely,  and  the  ovisac  contracting  energetically  at  the  same  moment,  the  embryo 
is  suddenly  and  forcibly  expelled  into  the  surrounding  water.  No  sooner  however 
does  it  escape  than  it  begins  to  swim  about  with  the  peculiar  semicircular  movements 


340 


MR.  J.  DALRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 


of  the  parent,  and  a few  moments  after  is  actively  engaged  in  searching  for  its 
food. 

Such  is  the  most  common  form  of  reproduction  ; but  towards  the  latter  end  of  the 
season,  the  females  are  found  with  a totally  different  form  of  ovum  within  them, 
Plate  XXXIV.  fig.  9.  This  ovum  is  spherical  and  dark,  the  outer  covering  appearing 
to  consist  of  an  aggregation  of  cells  whose  rounded  form  may  best  be  seen  at  the 
circumference,  where  they  appear  clear  and  semi-transparent.  Beneath  this  external 
layer  is  a second  stratum  of  cells  containing  pigmentary  molecules,  that  obscure  the 
view  of  the  yelk  within,  although  there  may  be  faintly  seen  four  or  five  larger  cells, 
with  so  highly  a refracting  outline  as  to  give  them  much  the  appearance  at  least  of 
oil-globules,  Plate  XXXIV.  fig.  6.  As  the  ovum  becomes  a little  further  advanced  the 
peripheral  cells  are  expanded,  slightly  club-shaped  and  striated,  giving  the  whole 
ovum  the  aspect  of  a dark  spherical  body  regularly  covered  with  fine  strise  (Plate 
XXXIV.  fig.  7),  radiating  from  a centre : from  the  want  of  general  transparency  no 
distinct  germinal  vesicle  can  be  seen. 

1 have  not  had  sufficient  opportunities  to  trace  the  further  development  of  these 
ova,  but  Mr.  Brightwell  of  Norwich,  an  excellent  and  most  accurate  observer,  has 
watched  them  for  some  months  after  their  expulsion  from  the  parent,  without  ob- 
serving any  further  change.  These  ova  are  however  so  totally  distinct  in  their  phy- 
siological relations  to  the  production  of  the  embryo  from  the  germinal  vesicle  of  the 
ovum  lying  naked  in  the  ovisac,  that  I think  it  probable  they  are  destined  to  remain 
through  the  winter  undeveloped,  until  the  following  year,  as  it  will  be  seen  that  the 
period  of  the  summer,  during  which  this  animalcule  is  found,  is  unusually  short,  as 
compared  with  the  date  of  existence  of  congenerous  species. 

A third  appearance  (or  description  of  ovum)  is  met  with  in  the  ovisac  of  the 
parent  female.  We  observe  an  embryo  developed  gradually  from  a germinal  vesicle, 
until  it  begins  to  assume  a definite  shape  and  independent  movement,  when  we  are 
at  once  struck  with  the  great  difference  of  its  form,  size  and  organization.  This  is 
the  male,  and  as  it  is  in  itself  most  curious,  and  as  I believe  up  to  this  time  quite 
new  and  unique,  it  will  require  special  Klescription. 

This  male  (Plate  XXXIV.  fig.  1 1)  is  about  three-fifths  the  size  of  the  female,  generally 
resembling  it  in  shape,  but  more  flattened  at  the  lower  part  or  fundus,  and  more 
prolonged  at  the  side  corresponding  to  the  vaginal  opening  in  the  female,  and  which 
in  the  male  presents  a similar  valvular  opening  though  comparatively  smaller  in  ex- 
tent, Plate  XXXIV.  fig.  1 2 E.  Within  this  valve  is  observed  a short  canal  leading  to  a 
large  spherical  bag  (Plate  XXXIV.  fig.  12  G),  which  may  be  distinctly  seen  filled  with 
molecular  bodies  in  constant  tremulous  movement.  From  this  sac,  which  I shall 
denominate  the  sperm-bag,  a short  but  thick  rounded  body  (Plate  XXXIV.  fig.  12  F) 
projects  into  the  canal  before  mentioned  as  leading  to  the  lateral  opening,  and  around 
the  extremity  of  this  projecting  process,  and  even  within  it  to  a short  distance,  is  a 
visible  ciliary  motion  indicating  a canal  (Plate  XXXIV.  fig.  14  C) : on  the  neck  of  the 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


341 


sperm-bag  is  a fasciculus  of  muscular  fibres  (Plate  XXXIV.  fig.  14  B)  which  are  inserted 
along  the  commencement  of  this  evident  'penis,  and  over  the  latter  organ  the  mem- 
branous sheath  is  reflected.  Muscular  bands  arising  from  the  tegumentary  parietes 
of  the  animal,  in  the  vicinity  of  the  valvular  opening,  go  to  be  inserted  into  the  root 
of  the  penis  (Plate  XXXIV.  fig.  14  A A),  and  may  be  frequently  observed  drawing  it 
up  to  the  opening,  and  even  extending  it  beyond  the  body  of  the  animal.  Muscles 
also  for  the  purpose  of  opening  the  valve  (Plate  XXXIV.  fig.  14  EE),  very  similar  to 
those  for  the  same  purpose  in  the  female,  and  the  bands  which  bring  the  penis  forward, 
clearly  show  it  to  be  an  extrusory  organ,  and  form  a complete  male  apparatus. 

The  sperm-bag  evidently  contains  active  spermatozoa  (Plate  XXXIV.fig.  13), having 
an  oval  flattened  body  (of  a high  refracting  power),  and  a caudal  appendage,  that, 
while  in  the  sac,  is  in  constant  vibratile  movement ; they  are  somewhat  larger  than, 
and  of  the  same  general  form  as,  human  spermatozoa. 

I myself  have  never  observed  any  action  beyond  the  extrusion  of  the  penis,  but 
my  friend  Mr.  Brightwell  has  observed  in  seven  different  instances  the  direct  copula- 
tion of  the  two  sexes.  The  following  quotation  from  his  notice  of  the  fact  in  the 
Annals  of  Natural  History  for  September  1848,  clearly  demonstrates  this  important 
circumstance. 

“ Observations  as  to  the  Union  between  the  Sexes. 

“June  15th. — Placed  a male  and  six  females  in  a small  glass  trough  by  themselves, 
and  two  males  and  about  thirty  females  in  a large  trough. 

“June  16th,  between  7 and  8 a.m. — On  examining  the  small  trough  observed  that 
the  male  on  approaching  one  of  the  females  attached  himself  to  its  side  by  the  sper- 
matozoid  projection,  and  remained  so  attached  from  twenty  to  thirty  seconds.  The 
same  male  acted  precisely  in  the  same  manner  with  four  other  females.  These  five 
connexions  took  place  in  about  fifteen  minutes. 

“At  5 p.M. — Saw  one  of  the  males  in  the  larger  trough  attach  himself  to  a young 
one  of  the  other  sex  for  about  twenty  seconds,  and  afterwards  to  a full-grown  female 
for  a somewhat  longer  time.  Saw  this  last  connexion  in  a clear  light  most  distinctly. 
The  end  of  the  sperm-tube  was  attached  to  the  side  of  the  female,  and  the  rest  of  the 
body  of  the  male  was  quite  free.  Saw  the  same  male  soon  after  fix  itself  by  its  head 
to  the  glass  and  remain  so  for  thirty  seconds,  and  during  this  time  it  continued 
puffing  out  and  drawing  in  the  sides  of  its  body  as  if  to  give  them  their  utmost  dila- 
tation. 

“June  20th,  5 p.m. — Placed  a young  female  and  a male  in  a trough  by  themselves 
and  watched  them  very  frequently  till  eleven  at  night,  and  though  they  came  very 
near  each  other  no  conjunction  took  place. 

“June  21st,  8 a.m. — Found  the  female  dead  and  the  male  alive.  Put  three  other 
females  to  this  male,  and  in  a few  minutes  saw  the  male  as  soon  as  he  approached 
one  of  the  females  attach  his  sperm-tube  to  its  side  and  remain  so  attached  fifty 

2 Y 


MDCCCXLIX. 


342 


MR.  J.  DALRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 


seconds.  Soon  afterwards  he  attached  himself  to  another  very  young  female  and, 
remained  so  attached  seventy  seconds.  Could  discern  this  latter  connexion  of  the 
end  of  the  sperm-tube  with  the  side  of  the  female  very  distinctly. 

“ 4 p.M. — Saw  in  the  trough,  by  the  aid  of  the  microscope  with  a one-inch  achromatic 
object-glass,  a conjunction  of  a male  with  a female.  On  approaching  the  female  the 
male  attached  himself  by  the  sperm-tube  to  her  side,  and  remained  so  attached 
nearly  a minute.  Saw  this  most  clearly,  but  owing  to  the  movement  of  the  animals 
in  the  water  it  is  almost  impossible  to  see  more  than  that  there  is  a distinct  adhesion. 

“ Most  of  the  above  observations  were  made  with  a single  lens  only,  of  two  inches 
focus,  and  the  others  with  the  microscope.” 

So  acute  an  observer  as  Mr.  Brightwell  could  not  possibly  have  been  mistaken 
in  the  fact  so  repeatedly  observed,  and  it  leaves  us  therefore  in  no  doubt  as  to  the 
dioecious  character  of  this  singular  family ; but  there  is  another  circumstance  con- 
nected with  the  anatomy  of  the  male,  so  curious  as  possibly  to  be  unique.  The  male 
I have  said  possesses  the  same  general  figure  as  the  female,  it  has  also  the  contractile 
vesicle,  which  I have  ventured  to  name  the  respiratory  sac  (Plate  XXXIV.  fig.  12 
D C),  as  well  as  the  fibres  furnished  with  the  vibratory  or  ciliated  tags,  subservient 
to  the  office  of  a circulation.  It  has  also  the  ordinary  rotiferous  apparatus  at  the 
head,  through  the  agency  of  which  its  various  movements  of  locomotion  are  performed ; 
the  pink  eye  (Plate  XXXIV.  fig.  12  B)  is  distinct.  It  has  however  no  mandibles, 
no  pharynx,  oesophagus,  pancreatic  glands  or  stomach  ; there  appear  to  be  no  organs 
of  prehension,  deglutition,  digestion  or  assimilation.  At  the  lower  part  of  the 
animal,  on  the  other  side  of,  and  opposite  to  the  valvular  opening,  are  three  small 
oval  bodies  (Plate  XXXIV.  fig.  12  H),  massed  together,  having  no  communications  by 
tube  or  otherwise,  but  fixed  in  their  place  by  short  ligaments,  that  may  be  rudiments 
of  a stomach. 

They  are  not  testes,  for  they  have  no  communications  with  the  sperm-bag,  and  they 
do  not  exist  in  the  female.  I have  therefore  provisionally  regarded  them  as  the 
rudiments  of  a digestive  apparatus. 

The  difference  of  sex  in  these  two  forms  is  plainly  evidenced  by  the  fact,  not  only 
of  the  difference  of  structure,  the  presence  of  active  spermatozoa  in  the  male,  but  by 
the  observed  fact  of  the  intromission  of  the  male  organ  into  the  vaginal  canal  of 
the  female.  That  the  male  animal  is  produced  by  the  female  and  developed  within 
the  ovisac  in  the  same  manner  as  the  female  embryo,  is  also  proved  by  many  observa- 
tions ; and  one  of  the  drawings  of  the  male  has  been  made  from  a specimen  stiU  in 
the  interior  of  the  parent,  and  even  at  that  period  having  its  sperm-bag  filled  with 
active  spermatozoa. 

Thus  this  animal  is  not  androgynous,  and  a careful  reconsideration  of  the  whole 
family  of  Hydatina  is  desirable  to  determine  whether  this  law  prevails  in  this  exten- 
sive group  of  infusory  animalcules.  Had  the  male  not  been  traced  ah  ovo,  or  had  it 
been  met  with  apart  from  female  specimens  in  the  water,  it  had  been  taken  for  a 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


343 


wholly  distinct  species,  and  I can  easily  imagine  the  males  of  other  species  may  so 
far  differ  in  size  and  apparent  organization,  as  to  have  been  mistaken  for  distinct 
races,  and  their  physiological  position  overlooked. 

The  absence  of  all  organs  for  the  sustentation  of  life  by  food  leads  to  the  belief 
that  it  is  created  for  a single  purpose,  and  that  its  duration  or  term  of  existence  is 
very  short.  In  this  respect  it  somewhat  resembles  the  drone  or  male  bee,  whose 
utility  seems  confined  to  the  impregnation  of  the  perfect  female  or  queen.  The  short 
existence  of  this  male  is  further  proved  by  the  fact  that  it  is  impossible  to  keep  these 
animals  alive  for  any  extended  space,  and  the  observer  who  has  not  frequent  access  to 
the  natural  pools  in  which  they  exist,  is  dependent  for  subjects  of  experiment  on 
their  occasional  production  by  the  females  in  the  water  wherein  they  are  confined. 

That  a single  impregnation  is  sufficient  for  the  production  of  many  young,  is  proved 
by  the  female  continuing  to  breed  in  water  in  which  no  male  can  be  discovered ; but 
young  females  so  produced  will  not  go  on  to  develope  others  unless  a male  be  born 
amongst  them. 

In  what  light  then  are  we  to  look  upon  an  animal  wanting  those  organs,  that  in  the 
most  elementary  beings  appear  to  constitute  the  almost  entire  structure  having  a single 
function  to  discharge,  that  of  continuing  the  species,  which  once  effected,  it  perishes  ? 
Such  indeed  appears  to  be  the  case,  and  is  another  of  those  marvellous  instances  of 
endless  variety  in  the  accomplishment  of  a particular  object  by  the  Creator,  in  which 
His  works  abound. 

A few  words  are  necessary  as  to  the  habitat  of  this  curious  animal.  It  was  first 
discovered  by  Mr.  Brightwell  in  1841,  in  a pit  immediately  without  the  city  of  Nor- 
wich. For  a long  time  it  was  met  with  in  no  other  locality,  although  constant  search 
was  made  for  it  in  localities  likely  to  abound  in  Infusoria.  Even  in  this  particular 
pond  in  some  summers  no  specimens  have  been  detected,  while  in  others  it  has 
swarmed  in  June,  July  and  August.  It  has  however  this  year  been  discovered  by 
Mr.  King  of  Norwich  in  a pool  on  Mousehold  Heath,  within  a short  distance  of  the 
same  city.  I have  for  many  years  been  accustomed  to  search  the  pits  and  ditches  in 
the  neighbourhood  of  London,  and  although  almost  every  genus  described  by  Ehren- 
BERG  has  furnished  some  species,  and  abundance  of  Notornmata,  especially  at  Hil- 
lingdon near  Uxbridge,  there  have  been  seen  no  specimens  of  this  curious  animal 
until  by  chance  I detected  it  in  August  of  the  present  year  in  a pond  in  Warwick- 
shire, not  far  from  Leamington.  As  however  infusorial  animalcules  have  a very  wide 
range,  it  is  to  be  hoped  it  will  hereafter  be  more  extensively  met  with  than  hitherto, 
and  more  especially  as  from  its  exquisite  transparency  and  the  perfection  of  its  ova- 
rjes  and  ovisacs,  as  well  as  from  the  discovery  of  a separate  male,  the  process  of 
development  can  be  so  easily  watched  and  traced  from  its  earliest  commencement. 
As  far  as  has  been  hitherto  observed,  the  development  of  the  ovum,  through  all  the 
phases  of  germinal  vesicle,  granular  nuclei,  nucleated  cell,  and  the  conversion  of  cell 
into  tissue,  appears  to  follow  the  same  type  as  has  been  so  well  described  by  Burdach, 

2 Y 2 


344 


MR.  J.  DiiLRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 


Von  Baer,  Von  Siebold,  Bischoff,  Barry  and  a host  of  others.  The  rapidity  of  the 
processes,  as  well  as  the  great  clearness  with  which  the  changes  can  be  seen,  are  very 
favourable  for  observation  ; while  the  viviparous  nature  of  the  animal  assimilates  the 
conditions  more  to  that  of  higher  organizations,  than  where  development  takes  place 
in  a true  egg  expelled  from  the  body  of  the  mother,  and  dependent  upon  its  own  vis 
insita  alone. 


Explanation  of  the  Plates. 

PLATE  XXXIII. 

Fig.  1.  Exhibits  the  animalcule,  of  which  the  preceding  pages  are  a description,  seen 
in  the  position  most  generally  observed,  viz.  in  profile. 

A.  The  ciliated  coronet  that  surrounds  the  head. 

B.  The  mouth  or  anterior  aperture. 

C.  The  pink  eye. 

D.  The  ganglionic  mass  on  which  the  eye  is  placed. 

E.  The  jaws  or  mandibles. 

F.  The  pharyngeal  cavity. 

G.  The  oesophagus. 

H.  Salivary  or  pancreatic  glands. 

I.  The  stomach. 

K.  The  circulatory  apparatus. 

L.  The  ciliated  tags  appended  thereto. 

M.  Muscles. 

N.  Contractile  or  pulmonary  sac. 

O.  Ovary. 

P.  Ovisac  surrounding. 

Q.  An  embryo. 

R.  Circular  bands  on  the  integument, 

S.  Vaginal  or  posterior  orifice. 

T.  Lateral  aperture,  ciliated  or  setaceous. 

Fig.  2.  Represents  the  animalcule  seen  frontwise  or  on  the  abdominal  aspect ; organs 
symmetrically  placed. 

A.  The  axis  of  the  jaws. 

B B.  Muscles  moving  the  rami  of  the  jaws.  , 

C.  The  pharynx. 

D.  The  oesophagus. 

E.  Salivary  glands. 

F.  Circulatory  apparatus,  with 


mi  Trarnmz^fmi  PokWAWp-lU. 


-$ 


t 

I 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


345 


G G.  Ciliated  or  vibratile  tags. 

H.  Semilunar  slit  of  the  vaginal  orifice. 

I.  Internal  valve  of  vagina. 

K.  Ovisac. 

L.  Contractile  vesicle. 

O O.  Ovary. 

Fig.  3.  The  forcipated  jaws. 

A.  The  axis. 

B.  The  short  ramus. 

C C.  Processes  for  the  attachment  of  muscles. 

E.  Joint. 

F.  Long  ramus  of  the  jaws. 

G.  Lateral  tooth  or  hook. 

H.  External  or  second  slender  forceps. 

I.  Sharp  or  hooked  extremity  of  jaw. 

K.  Flat  or  chisel-shaped  tooth. 

Fig.  4.  Represents  the  oral  apparatus  seen  by  looking  directly  down  upon  the  head. 

The  forcipated  jaws  are  symmetrically  placed,  surrounded  by  powerful 
masses  of  muscles,  and  situated  above  the  pharyngeal  cavity.  The 
pink  eye  is  seen  in  front  of  the  jaws  and  somewhat  to  one  side,  over- 
looking the  entrance  into  the  pharynx. 

Fig.  5.  A salivary  gland,  highly  magnified,  650  diameters. 

The  gland  shows  the  secreting  cells  with  their  central  nuclei  dispersed  in 
a granular  stroma  while  around  what  appears  to  be  a duct,  entering 
the  oesophagus  immediately  above  the  stomach  ; the  cells  appear  to  give 
place  to  a delicate  granular  structure,  which  may  indicate  the  resolu- 
tion of  the  cells  into  the  secreted  matter. 

Fig.  6.  Represents  the  multilocular  stomach,  with  the  oesophagus  and  salivary  or 

pancreatic  glands  attached. 

Each  loculus  of  the  stomach  has  a clear  nucleus  on  its  centre,  and  while 
the  whole  cavity  is  a digestive  sac,  it  is  not  improbable  the  loculi  and 
their  nuclei  represent  rudimentary  hepatic  caeca. 

Within  the  stomach  are  seen  a Closterium  and  a Gonium  on  which  the 
animalcule  has  fed. 

Muscular  fibres  may  be  seen  passing  over  the  stomach  sunk  in  the  de- 
pressions between  the  sacculi  of  the  organ  ; and  attached  to  the  fundus 
are  slender  muscles,  which  are  also  fixed  to  the  lowest  part  of  the  tegu- 
mentary case  of  the  animalcule,  and  serve  to  retract  the  stomach  after 
displacement  and  regurgitation  of  the  digested  food. 

Fig.  7-  Shows  a female  animalcule,  for  the  purpose  of  representing  more  distinctly 

the  circulatory  organs  (A),  with  their  attached  ciliated  or  vibratile  tags  (B), 


346  MR.  J.  DALRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY 

and  the  contractile  vesicle  or  respiratory  bag  (C).  Both  it  and  the  ovisac 
(D)  appear  to  communicate  with  the  valvular  opening  or  vagina  (E),  but 
whether  by  a separate  or  common  passage  is  as  yet  doubtful.  The  ovisac 
is  partially  contracted  and  thrown  into  folds,  and  attached  by  muscular  or 
ligamentous  bands  to  the  yoke-shaped  ovary  (F).  The  stomach  (G)  is  dis- 
placed to  one  side. 

Fig.  8.  Represents  the  muscular  system  and  what  appears  to  be  a rudimentary  ner- 
vous system. 

The  muscular  bands  which  retract  the  body  of  the  animalcule  are  seen 
rising  by  broad  origins  from  the  firm  coronet  of  the  animalcule,  and 
pass  down  the  interior  of  the  body,  free  and  unattached,  to  be  inserted 
by  digitated  processes  into  those  circular  tegumentary  rings  which 
have  been  described  as  vessels  by  Ehrenberg. 

Over  the  stomach,  which  is  here  represented  empty  and  somewhat  flat- 
tened, muscular  bands  may  be  seen  extending  from  the  oesophagus  to 
its  very  fundus.  Two  delicate  muscular  bands  are  fixed  to  the  interior 
or  bottom  of  the  tegumentary  case,  and  inserted  into  the  fundus  of  the 
stomach,  and  are  retractors  of  this  organ. 

A.  Shows  the  pink  eye  situated  in  a mass  of  nervous  or  ganglionic  matter, 
from  which  proceeds  a delicate  chord,  having  at  B two  ganglionic  cor- 
puscles and  terminating  at  the  two  setaceous  tubercles  at  the  side  of  the 
animalcule  at  E.  At  C,  delicate  nervous  chords  go  off*  to  be  distributed 
to  the  stomach,  pancreatic  or  salivary  glands  and  ovaries ; and  at  D, 
another  ganglion  appears  to  give  off  fibrillee  too  doubtful  to  be  here  in- 
dicated. 

PLATE  XXXIV. 

Fig'  1.  A portion  (one  horn)  of  an  ovary,  magnified  700  diameters,  showing  the  gra- 
nular stroma,  and  the  vesicles  and  their  included  nuclei  and  bright  nucleoli. 

Fig.  2.  An  ovum,  as  yet  attached  to  the  ovary,  exhibiting  the  granular  yelk,  and  the 
excentric  germinal  vesicle,  with  a bright  nucleus. 

Fig.  3.  The  resolution  of  the  yelk  into  several  cells,  each  having  a nucleus. 

Fig.  4.  A further  development  of  nucleated  cells,  beginning  to  be  massed  together  in 
groups. 

Fig.  5.  Symmetrical  arrangement  of  the  groups  of  cells,  the  uppermost  group  indi- 
cating the  future  position  of  the  head. 

Fig  5".  A condition  of  the  ovum  seen  once  only,  in  which  the  yelk  appears  divided 
into  two  masses,  without  regular  nucleated  cells  : a few  oil-globules  are  seen 
irregularly  distributed.  Whether  this  be  a fertile  ovum  is  doubtful,  but 
further  changes  were  not  observed,  the  parent  animalcule  dying. 


4 


Thllraiu.  mZ{yi\:^ThMmi p.  Ug 


II 


f3a.riT.- 


ANIMALCULE  ALLIED  TO  NOTOMMATA. 


347 


Figs.  6,  7j  8,  8"  and  9,  represent  the  ova  in  shelly  cases,  supposed  to  be  ova  that  per- 
sist unhatched  during  the  winter,  or  at  least  which  are  not  developed  within 
the  body  of  the  parent  female. 

Fig.  6.  The  early  stage  of  the  ovum,  through  the  coriaceous  coat  of  which  are  seen 
numerous  oil-globules  in  the  yelk ; the  ovum  is,  however,  too  opake  to  per- 
mit the  germinal  vesicle  to  be  seen. 

Fig.  7.  Further  advancement  of  the  ovum,  in  which  a peculiar  striated  appearance  of 
the  flattened  cells,  which  constitute  the  outer  covering,  may  be  observed. 

Fig.  8.  A similar  ovum,  and  fig.  8",  a portion  of  these  flattened  cells,  more  highly 
magnified,  to  show  to  what  is  due  the  peculiar  striated  appearance. 

Fig.  9.  An  ovum  ready  to  be  expelled,  in  which  the  dark  pigment  has  been  added, 
which  obscures  all  appearance  of  cells  except  at  the  margin. 

Fig.  10.  Represents  the  impregnated  female  and  the  development  of  the  ova,  those 
destined  to  evolve  living  embryos. 

In  this  figure  the  ovisac  contains  four  ova  in  different  stages  of  maturity, 
viz.  one  (A)  situated  at  the  most  inferior  part  of  the  animalcule,  already 
nearly  developed,  in  which  the  various  internal  organs  are  seen  almost 
perfected ; cell  nuclei  are  still  visible  in  the  two  long  muscles  of  the 
body,  and  as  the  embryo  is  seen  frontwise,  the  organs  are  observed 
symmetrically  placed. 

Immediately  above  this  embryo  is  a second  (B)  obliquely  situated,  with 
the  head  downwards,  and  partially  obscured  by  an  ovum  (C)  lying  over 
it,  which  has  proceeded  only  as  far  as  the  conversion  of  the  granular 
yelk  into  nucleated  cells  ; while  above  this  is  a fourth  (D)  still  attached 
to  the  ovary,  in  which  the  germinal  vesicle  is  very  obvious  and  excen- 
trically  placed. 

Fig.  1 1 . Represents  the  male  animalcule  in  which  the  various  organs  are  distinctly 
expressed.  This  specimen  was  found  swimming  free  in  water,  taken  from 
a pond  in  Warwickshire  in  August  1848.  The  spermatozoa  are  distinctly 
seen  in  the  sperm-bag. 

Fig.  12.  A male  animalcule  drawn  from  a specimen  still  in  the  ovisac  of  the  female. 

A.  The  ciliated  coronet. 

B.  The  pink  eye. 

C.  The  circulatory  organs  with  their  ciliated  tags. 

D.  Contractile  or  pulmonary  sac. 

E.  The  lateral  opening,  through  which 

F.  The  penis,  or  male  extrusory  organ,  is  projected. 

G.  The  sperm-bag  filled  with  spermatozoa. 

H.  The  glandiform  bodies,  or  rudimentary  structures,  uses  at  present  un- 
ascertained. 

Pig  13.  Spermatozoa  from  the  sperm-bag,  obtained  by  compression. 


348  MR.  J.  DALRYMPLE’S  DESCRIPTION  OF  AN  INFUSORY  ANIMALCULE. 

Fig-.  14.  Exhibits  the  organs  of  generation. 

A A.  Muscles  which  extrude  the  penis. 

B.  Fasciculus  of  muscular  fibres,  which  arising  from  the  neck  of  the  sperm- 
bag  are  inserted  on  the  body  of  the  penis  and  expel  the  spermatozoa. 
“ Ejaculatores  seminis.” 

C.  Preputial  sheath,  within  which  is  seen  a ciliary  movement. 

D.  Epithelium  lining  the  sperm-bag,  seen  by  gently  expressing  the  sperma- 
tozoa. 

E.  Muscles  which  open  the  external  valve  or  lateral  opening  through  which 
the  penis  passes. 


[ 349  ] 


XIX.  On  the  Motion  of  Gases. — Part  II. 

By  Thomas  Graham,  Esq.,  F.R.S.,  F.C.S.,  Professor  of  Chemistry  in  University 
College,  London ; Hon.  Fellow  of  the  Royal  Society  of  Edinburgh ; Corresponding 
Member  of  the  Institute  of  France,  of  the  Royal  Academies  of  Sciences  of  Berlin 
and  Munich,  of  the  National  Institute  of  LFashington,  S^c. 


Received  June  21, — Read  June  21,  1849. 


All  experiments  on  the  velocity  with  which  different  gases  rush  into  a vacuum, 
or  pass  under  pressure  through  an  aperture  in  a thin  plate,  are  in  strict  accordance 
with  the  physical  law  that  the  times  of  passage  for  equal  volumes  are  proportional  to 
the  square  roots  of  the  densities  of  the  various  gases.  Besides  being  the  law  of 
“ Effusion,”  this  is  also  the  law  of  the  Diffusion  of  one  gas  into  an  atmosphere  of 
another  gas.  The  result  in  both  cases  is  simply  and  exclusively  a consequence  of 
specific  gravity. 

The  velocity  with  which  gases  of  different  nature  pass  through  a tube  is  necessarily 
much  influenced  by  the  law  of  their  effusion,  when  the  tube  is  short  and  approaches 
in  character  to  an  aperture  in  a thin  plate.  But  if  the  length  of  the  tube  is  progres- 
sively increased,  its  diameter  or  the  aperture  remaining  constant,  then  while  the  re- 
sistance increases  and  the  passage  for  all  gases  becomes  greatly  slower,  the  velocities 
of  the  different  gases  are  found  rapidly  to  diverge  from  those  of  their  effusion.  The 
velocities  of  different  gases  appear  at  last  however  to  attain  a particular  ratio  with  a 
certain  length  of  tube  and  resistance ; and  preserve  the  same  relation  to  each  other 
for  greater  lengths  and  resistances.  After  attaining  this  constant  ratio,  the  passage 
of  all  the  gases  becomes  slower,  exactly  in  proportion  to  the  increased  length  of  the 
tube,  that  is,  in  proportion  to  the  resistance.  The  different  gases  are  now  equally 
affected  by  the  resistance,  and  their  relative  velocities  are  therefore  undisturbed  and 
remain  constant.  The  effect  of  the  law  of  effusion  upon  the  velocities  is  no  longer 
sensible,  and  appears  to  be  eliminated. 

As  the  rates  of  passage  of  different  gases  through  a tube  appear  to  depend  upon  a 
new  and  peculiar  property  of  gases,  I have  spoken  of  it  as  the  Transpiration  or  Trans- 
pirability  of  gases.  The  rates  of  transpiration  appear  not  to  be  affected  by  the  ma- 
terial of  the  tube,  as  they  are  found  the  same  for  capillary  tubes  of  glass  and  of 
copper  and  for  a porous  mass  of  stucco.  I may  add  that  such  experiments  exhibit  a 
constancy  and  possess  a neatness  and  precision  which  is  very  extraordinary.  The 
experiments  of  M.  Poiseuille  indicate  an  equally  remarkable  constancy  and  pre- 

MDCCCXLIX.  2 z 


350 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


cision  of  result  in  the  passage  of  Liquids  through  capillary  tubes^  which  has  been 
fully  confirmed  by  M.  Regnault*. 

The  experiments  of  my  former  paper  afford  good  grounds  for  assuming  the  ex- 
istence of  a relation  in  the  transpirability  of  different  gases,  of  an  equally  simple 
nature  as  that  which  is  recognised  among  the  specific  gravities  of  gases,  or  even  as 
the  still  more  simple  ratios  of  their  combining  volumes.  Compared  with  solids  and 
liquids,  matter  in  the  form  of  gas  is  susceptible  of  small  variation  in  physical  pro- 
perties, and  exhibits  only  a few  grand  features.  These  differences  of  property  which 
are  preserved  amidst  the  prevailing  uniformity  of  gases,  may  well  be  supposed  to  be 
among  the  most  deep-seated  and  fundamental  in  their  nature  with  which  matter  is 
endowed.  It  was  under  such  impressions  that  I have  devoted  an  amount  of  time 
and  attention  to  the  determination  of  this  class  of  numerical  constants,  which  might 
otherwise  appear  disproportionate  to  their  value  and  the  importance  of  the  subject. 
As  the  results,  too,  were  entirely  novel,  and  wholly  unprovided  for  in  the  received 
view  of  the  gaseous  constitution,  of  which  indeed  they  prove  the  incompleteness,  it 
was  the  more  necessary  to  verify  every  fact  with  the  greatest  care. 

Perhaps  the  most  general  and  simple  result  which  I can  offer  is,  that  the  transpira- 
tion velocity  of  hydrogen  is  exactly  double  that  of  nitrogen.  These  gases  it  will  be 
remembered  have  a less  simple  relation  in  density,  namely  1 to  14.  This  was  the 
conclusion  respecting  the  transpiration  of  these  gases  in  my  former  paper,  and  I have 
obtained  since  much  new  evidence  in  its  favour.  The  transpirability  of  carbonic 
oxide,  like  the  specific  gravity  of  that  gas,  appears  also  to  be  identical  with  tliat  of 
nitrogen. 

The  result  which  I would  place  next  in  point  of  accuracy  and  importance  is,  that  the 
transpiration  velocity  of  oxygen  is  related  to  that  of  nitrogen  in  the  inverse  ratio  of 
the  densities  of  these  gases,  that  is  as  14  to  16.  In  equal  times  it  is  not  equal  volumes 
but  equal  weights  of  these  two  gases  that  are  transpired;  the  more  heavy  gas  being 
more  slowly  transpired  in  proportion  to  its  greater  density.  Mixtures  of  oxygen  and 
nitrogen  have  the  mean  velocity  of  these  two  gases,  and  hence  the  time  of  air  is  also 
found  to  be  proportional  to  its  density  when  compared  with  the  time  of  oxygen. 

The  relation  between  nitrogen  and  oxygen  is,  I believe,  equally  precise  as  that  be- 
tween nitrogen  and  hydrogen.  The  densities  calculated  from  the  atomic  weights  of 
oxygen  and  nitrogen,  namely,  16  and  14,  being  1 for  oxygen,  O'OOlO  for  air  and 
0*8750  for  nitrogen  ; the  observed  times  of  transpiration  of  equal  volumes  of  the  same 
gases  are  for  oxygen  1,  air  0*8970  to  0*9010,  and  for  nitrogen  from  0*8680  to  0*8708. 

These  slight  deviations  I look  upon  as  of  the  same  character  as  those  which  accu- 
rate determinations  of  the  densities  of  the  same  gases  indicate  from  their  calculated 
or  theoretical  density ; the  observed  densities  of  air  and  nitrogen  being  0*9038  and 

* Rapport  sur  un  Memoire  de  M.  le  Docteur  Poiseuille,  ayant  pour  titre,  “ Recherches  experimentales  sur 
le  mouvement  des  liquides  dans  les  tubes  des  trbs-petits  diametres.”  Annales  de  Chimie  et  de  Physique* 
s^rie,  t.  vii.  p.  50. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


351 


s 


0-8785  referred  to  oxygen  as  unity  (Regnault),  instead  of  0-9010  and  0-8750;  or 
the  observed  difference  in  density  is  sensibly  less  than  it  should  be  by  theory.  The 
departure  from  the  law  in  the  transpiration  of  the  same  gases  is  certainly  somewhat 
wider,  and  it  is  in  the  opposite  direction ; the  difference  in  the  observed  times  of  trans- 
piration being  greater  instead  of  less  than  the  calculated  times. 

The  points  respecting  transpiration  which  still  most  demand  consideration  are  the 
following : — 

1.  Determination  of  the  resistance  and  of  the  dimensions  of  the  capillary  at  which 
the  transpiration  of  gases  becomes  normal ; and  the  properties  of  serviceable  capillary 
tubes. 

2.  New  determinations  of  the  transpiration  of  various  gases  and  vapours. 

3.  Influence  of  change  of  density  and  elasticity,  produced  by  change  of  pressure, 
upon  transpiration. 

4.  Influence  of  temperature  upon  transpiration. 

I.  CAPILLARY  TUBES  FOR  TRANSPIRATION. 

The  transpiration  of  some  gases  appears  to  become  sooner  normal  than  others,  that 
is,  in  capillary  tubes  which  are  less  elongated  or  less  contracted  than  is  necessary  for 
other  gases.  This  was  first  observed  on  breaking  down  and  using  portions  of  the  glass 
capillary  tube,  H of  my  former  paper,  which  was  comparatively  wide,  being  about 
0-0222  inch,  or  ^th  of  an  inch  in  diameter,  with  the  great  original  length  of  22  feet ; 
when  it  allowed  1 cubic  inch  of  air  to  pass  under  the  pressure  of  one  atmosphere 
into  a vacuum  in  15-64  seconds,  or  it  discharged  3-84  cubic  inches  of  air  per  minute. 

The  following  table  exhibits  the  times  of  transpiration  of  equal  volumes  of  several 
gases  by  this  capillary  reduced  in  length  to  a little  under  20  feet.  The  table  con- 
tains two  series  of  experiments.  The  first  is  the  transpiration  time  of  a constant 
volume  of  the  gases  drawn  from  a globular  vessel  standing  over  water,  into  a sustained 
vacuum.  This  vessel  was  terminated  above  and  below  by  glass  tubes,  forming  hollow 
axes  to  the  globe.  The  measure  transpired  was  the  capacity  of  the  vessel  between  a 
mark  on  the  lower  and  a mark  on  the  upper  tube,  and  amounted  to  56-5  cubic  inches. 
The  second  series,  which  consists  of  carbonic  acid  gas,  with  air  for  comparison,  is  the 
transpiration  of  these  gases  into  a nine-pint  jar  or  receiver  upon  the  plate  of  an  air- 
pump,  beginning  the  experiment  with  an  exhaustion  of  28-5  inches  by  the  attached 
barometer,  and  terminating  at  23-5  inches.  It  was  necessary  to  measure  the  volume 
of  carbonic  acid  in  this  manner  after  transpiration  and  not  before  it,  to  avoid  the 
error  which  the  solution  of  a portion  of  this  gas  in  water  might  introduce.  The  gases 
all  passed  through  a drying  tube  containing  asbestos  moistened  with  oil  of  vitriol, 
before  reaching  the  capillary. 


2 z 2 


352 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


Table  I. — Transpiration  by  Capillary  H 237*875  inches  in  length,  and  inch 

in  diameter. 


Gas  transpired. 

Experi- 
ment I. 

Experi- 
ment II. 

Mean. 

Air=l. 

Oxygen  =1. 

Observations. 

Oxygen  

Air 

Hydrogen  

Protocarb.  hydrogen  (CH^). 
Carbonic  oxide  

1146 

1032 

509 

631 

994 

1147 

1032 

510 

630 

995 

1146*5 

1032* 

509*5 

630*5 

994*5 

1*0000 

1*0000 

0*9001 

0*4443 

0*5499 

0*8674 

Bar.  29*696.  Temp.  67°  Fahr. 

Air  

Carbonic  acid 

798 

668 

799 

668 

798*5 

668* 

0*8366 

0*7529 

Bar.  29*602.  Temp.  69°  Fahr. 

I produce  these  results  principally  to  show  how  small  the  variation  is  in  carefully 
made  experiments,  not  amounting  to  more  than  1 second  in  times  which  exceed  1000 
seconds  for  two  of  the  gases,  as  well  as  to  afford  standard  numbers  to  compare  with 
those  obtained  for  reduced  lengths  of  the  same  tube. 


Table  II. — Transpiration  times  of  equal  volumes  by  Capillary  H of  different 

lengths. 


Length  of  capillary. 

Oxygen. 

Air. 

Carbonic 

oxide. 

Carbonic 

acid. 

Protocarburetted 

hydrogen. 

Hydrogen. 

237*875  inches=  1*0000 

1 

0*9001 

0*8674 

0*7529 

0*5499 

0*4443 

0*8539 

1 

0*8983 

0*4422 

0*6521 

1 

0*9009 

0*8681 

0*7585 

0*5506 

0*4434 

0*4513 

1 

0*9013 

0*8743 

0*7900 

0*5636 

0*4424 

0*3195 

1 

0*9131 

0*8793 

0*8501 

0*5826 

0*4041 

0*2149 

1 

0*9149 

0*8799 

0*8849 

0*6049 

0*3842 

0*1234 

1 

0*9131 

0*8790 

0*8802 

0*5860 

0*3924 

18*125  inches  = 0*0762 

1 

0*9138 

0*8879 

1*0395 

0*5948 

0*3879 

The  absolute  times  of  transpiration  varied  with  air  from  1032  seconds  for  the 
greatest  to  116  seconds  for  the  shortest  length  of  the  capillary. 

It  will  be  remarked  that  the  transpiration  times  of  air  and  hydrogen  are  preserved 
with  the  greatest  uniformity,  while  the  length  of  the  capillary  is  reduced  from  1 to 
0*4513,  air  varying  only  from  0*9001  to  0*9013,  and  hydrogen  from  0*4443  to  0*4424. 
The  variation  of  the  rate  of  carbonic  oxide  is  more  sensible  although  still  small, 
namely,  from  0*8674  to  0*8743.  Protocarburetted  hydrogen,  however,  rises  for  the 
same  change  in  the  tube  from  0*5499  to  0*5636,  and  carbonic  acid  still  more  con- 
siderably, namely,  from  0*7529  to  0*7900.  The  resistance  of  the  tube  is  insufficient 
for  shorter  lengths,  the  influence  of  effusion  becoming  manifest,  and  most  conspicu- 
ously so  in  carbonic  acid.  The  times  of  effusion  of  equal  volumes,  to  which  the  gases 
are  now  converging,  although  with  unequal  degrees  of  rapidity,  are,  for  oxygen  1, 
air  0*9507,  carbonic  oxide  0*9356,  carbonic  acid  1*1760,  protocarburetted  hydrogen 
0*7071,  and  hydrogen  0*2502. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


353 


An  important  conclusion  to  be  drawn  from  these  results  is,  that  the  transpiration 
of  all  gases  does  not  become  normal  for  the  same  length  of  tube  or  amount  of  resist- 
ance, but  that  a greater  length  of  the  tube  and  consequent  resistance  is  more  neces- 
sary for  some  than  for  others.  Carbonic  acid  in  particular,  of  which  the  effusion 
rate  differs  so  widely  from  its  transpiration  rate,  appears  to  require  a considerably 
greater  resistance  than  the  other  gases  transpired  to  bring  it  to  a uniform  rate. 
Indeed  the  results  respecting  that  gas  suggest  the  inquiry  whether  the  resistance  is 
sufficient  with  the  present  capillary  in  its  greatest  length,  and  whether  the  true  trans- 
piration time  for  this  gas  may  not  be  less  than  0*75,  the  number  provisionally 
adopted.  Let  us  therefore  observe  the  effect  of  greatly  increased  resistances  upon 
the  transpiration  of  this  and  other  gases. 

A thermometer  tube  of  the  finest  flat  bore  was  selected,  K,  of  which  52^  inches 
contained  only  13‘5  grains  of  mercury.  The  bore  was  not  quite  uniform,  0’6  grain 
of  mercury  occupying  2 inches  of  the  cavity  at  each  end  of  the  tube  and  2'3  inches 
near  the  middle.  Under  the  pressure  of  1 atmosphere,  1 cubic  inch  of  air  passed 
into  a vacuum  by  this  capillary  in  15  r3  seconds,  or  the  discharge  of  air  was  not  more 
than  O' 4 cubic  inch  per  minute.  The  resistance  was  therefore  ten  times  greater  than 
in  the  capillary  H when  of  its  greatest  length  of  22  feet. 

Air  and  other  gases  were  transpired  through  K into  a two-pint  jar  placed  upon  the 
plate  of  an  air-pump,  or  into  a space  amounting  to  71 ‘08  cubic  inches,  till  the  attached 
barometer  of  the  air-pump  fell  from  28‘5  to  25‘5  inches. 

(1.)  The  time  required  by  air  in  three  experiments  was  1075,  1073  and  1074 
seconds;  and  for  oxygen  in  two  experiments  1192  and  1192  seconds;  the  tempera- 
ture being  56°Fahr.  and  the  height  of  the  barometer  30T62  inches.  This  gives 
0'9010  as  the  transpiration  time  of  air,  referred  as  usual  to  the  time  of  oxygen  as  1, 
the  result  accidentally  coinciding  with  the  theoretical  number  for  air. 

(2.)  The  time  required  by  hydrogen  in  two  experiments  was  552  and  550  seconds, 
the  time  of  air  being  1081,  1079,  1082  and  1080  seconds;  thermometer  57°  and 
barometer  29*918  inches.  Dividing  the  mean  number  for  hydrogen  551  by  the  mean 
number  for  air  1080*5,  we  obtain  0*5099  as  the  time  of  hydrogen,  that  of  air  being  1. 
To  reduce  the  time  of  hydrogen  to  that  of  oxygen  as  1,  we  have  to  multiply  0*5099 
by  0*9010,  which  gives  0*4593  as  the  transpiration  time  of  hydrogen.  This  is  a con- 
siderable departure  from  the  theoretical  number  0*4375  ; but  it  was  found  to  be  due 
to  a small  addition  of  air  to  the  gas,  which  it  obtained  from  the  water  over  which  it 
stood  in  the  pneumatic  trough,  and  necessarily  much  longer  than  usual,  from  the 
slow  manner  in  which  it  was  removed  by  transpiration  through  the  present  capillary. 
In  a series  of  experiments  made  with  hydrogen  containing  1,2,4,25,  50  and  75  parts 
of  oxygen  in  100  of  the  mixture,  this  capillary  was  found  to  give  the  transpiration 
times  0*4901,  0*5055,  0*5335,  0*7750,  0*9061  and  0*9718.  Half  a per  cent,  of  air 
would  therefore  more  than  account  for  the  increased  time  observed  with  the  first 
hydrogen.  In  experiments,  also,  made  with  other  equally  fine  capillaries,  when  the 


354 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


hydrogen  was  preserved  in  a state  of  great  purity  by  transmitting  it  by  a bent  tube 
from  the  generating  retort  to  the  upper  part  of  the  pneumatic  receiver,  and  in  large 
volumes,  so  that  the  gas  never  passed  through  water,  and  was  retained  only  a very 
short  time  in  contact  with  the  surface  of  that  liquid,  the  transpiration  time  then  fell, 
as  will  afterwards  appear,  quite  as  low  as  the  theoretical  number. 

(3.)  The  transpiration  of  carbonic  oxide  took  place  in  1051  and  1051  seconds, 
against  1090  and  1089  seconds  for  air;  thermometer  58°  Fahr.,  barometer  29'866.  This 
gives  for  carbonic  oxide  the  transpiration  times  0‘9646,  air  = 1 ; and  0‘8690,  oxygen  = 1 . 
I'he  transpiration  time  of  the  same  gas  by  the  former  capillary  H wasO‘8674 ; while 
the  number  corresponding  with  the  theoretical  density  of  the  gas  is  0'8750. 

The  capillary  K was  now  shortened  to  39*375  inches,  and  the  following  experiments 
were  made  with  it. 

(1.)  Carbonic  acid  was  transpired  in  661  and  659  seconds,  thermometer  58°,  and 
barometer  30*024.  The  time  of  oxygen  was  900  and  903  seconds.  The  means  give 
0*7321  as  the  transpiration  time  of  carbnnic  acid,  a number  considerably  less  than 
0*75,  and  confirming  my  suspicion  that  the  latter  number  was  too  high,  and  that  the 
resistance  of  H was  not  sufficiently  great  to  eliminate  the  whole  influence  of  effusion 
in  this  gas.  It  may  be  remarked,  in  passing,  that  the  new  number  for  carbonic  acid 
approaches  0*7272,  which  is  equal  to  or  is  the  reciprocal  of  the  density  of  carbonic 
acid  gas.  Such  a relation  suggests  the  idea  that  carbonic  acid  possesses  the  time  of 
oxygen,  (of  which  gas,  carbonic  acid  contains  its  own  volume,)  diminished  by  the 
carbon  present,  which  gives  an  additional  momentum  corresponding  to  its  weight  to 
the  compound  gas,  and  acts  thus  entirely  in  increasing  its  velocity. 

In  another  series  of  experiments  the  numbers  were  659  and  659  for  carbonic  acid, 
against  900  and  902  for  oxygen;  thermometer  58°,  and  barometer  30*052.  This 
gives  0*7303  as  the  transpiration  time  of  carbonic  acid. 

(2.)  Without  entering  into  a detail  of  the  experiments,  I may  add,  that  the  capillary 
K of  its  present  length  gave  0*9034  as  the  transpiration  time  of  air  and  0 4500  as  the 
transpiration  time  of  hydrogen  ; the  time  of  the  latter  gas  being  undoubtedly  elevated 
by  a minute  impurity,  as  in  the  former  case. 

The  length  of  capillary  K was  now  reduced  to  26*25  inches,  and  in  order  to  in- 
crease the  transpiration  time,  which  fell  to  about  567  seconds  for  air,  the  range  of  the 
attached  barometer  observed  was  increased  from  3 to  5 inches,  the  observations  being 
made  at  28*5  and  23*5  inches  of  the  barometer  attached  to  the  air-pump. 

(1.)  The  times  for  air  were  946  and  945  seconds  ; the  time  for  oxygen  1053  seconds, 
giving  0*8979  as  the  transpiration  time  of  air;  thermometer  57°  and  barometer 
.30*096. 

(2.)  The  times  for  carbonic  acid  were  773  and  773  seconds,  the  times  for  air  ob- 
served immediately  before  being  942  and  943  seconds ; thermometer  57°  and  baro- 
meter 29*982.  This  gives  0*8202  as  the  transpiration  time  for  carbonic  acid  referred 
to  air,  and  0*7361  referred  to  oxygen. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


355 


The  length  of  the  capillary  K being  now  reduced  to  13*12.5  inches,  air  was  found 
to  enter  so  as  to  depress  the  attached  barometer  from  28*5  to  25*5  inches  in  284 
seconds,  and  from  28*5  to  23*5  inches  in  472  seconds ; thermometer  56°  and  baro- 
meter 29*758  inches.  To  obtain  longer  times,  the  two-pint  jar,  used  as  the  aspirator- 
jar,  was  replaced  by  the  six-pint  jar,  which  last  gives  an  available  vacuous  space 
estimated  at  201*78  cubic  inches.  The  fall  of  the  attached  barometer  continued  to 
be  observed  from  28*5  to  23*5  inches. 

(1.)  The  times  of  air  were  1348  and  1353  seconds;  the  times  of  oxygen  1498  and 
1499  seconds  ; thermometer  58°  and  barometer  29*628.  The  means  give  0*9013  as 
the  transpiration  time  of  air. 

Observing  only  through  the  smaller  range  of  the  attached  barometer,  namely,  from 
28*5  to  25*5  inches,  the  following  results  were  obtained : — 

(1.)  The  time  of  air  was  809,809  seconds. 

(2.)  The  time  of  carbonic  oxide  was  780  and  779  seconds. 

(3.)  The  time  of  hydrogen  was  399,  400  and  398  seconds. 

(4.)  The  time  of  carbonic  acid  was  658  and  657  seconds. 

The  experiments  were  made  successively  in  the  order  in  which  they  are  stated, 
with  the  thermometer  at  59°  and  the  barometer  from  29*450  to  29*422.  The  results 
may  be  given  as  follows  : — 


Table  III. — Transpiration  times. 


Air=l. 

Oxygen  = 1. 

Carbonic  oxide  

0-9635 

0-4932 

0-8127 

0-8671 

0-4438 

0-7314 

Hydrogen  

Carbonic  acid 

The  transpiration  times  of  the  second  column  are  obtained  by  multiplying  the 
times  of  the  first  column  by  0*9,  a number  which  represents  the  time  of  air  with  suf- 
ficient accuracy,  the  time  of  oxygen  being  1.  It  will  be  observed  that  the  number 
for  carbonic  oxide  remains  wonderfully  constant  for  all  lengths  of  K ; that  the  num- 
ber for  hydrogen  0*4438  now  approaches  more  nearly  to  0*4375,  probably  as  nearly 
as  a slight  impurity  of  the  gas,  resulting  from  its  short  contact  with  water,  would 
admit ; and  that  the  number  for  carbonic  acid  0*7314,  is  still  low,  and  does  not  differ 
much  from  0*7272. 

In  a second  series  of  experiments,  which  need  not  be  detailed,  numbers  corre- 
sponding closely  with  the  preceding  were  obtained ; namely,  0*9003  for  air,  0*8656 
for  carbonic  oxide,  and  0*7336  for  carbonic  acid. 

The  capillary  K was  reduced  to  8*75  inches,  or  to  one-sixth  of  its  original  length, 
the  six-pint  jar  being  retained  as  the  aspirator-jar,  and  the  fall  of  the  attached  baro- 
meter observed  from  28*5  to  23*5  inches. 

(1.)  The  times  of  air  were  933  and  933  seconds;  of  oxygen  1036,  1036  and  1037 


356 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


seconds  ; of  carbonic  oxide  897,  897  seconds ; thermometer  from  59°  to  60°,  and 
barometer  from  29*1  to  29' 134  inches.  These  experiments  give  the  following  transpi- 


ration times : — 

Oxygen 1 

Air 0*9003 

Carbonic  oxide 0*8656 


(2.)  The  times  of  air  were  920  and  920  seconds ; of  hydrogen  450  and  451  seconds  ; 
of  carbonic  acid  763,  762  seconds ; thermometer  58°,  barometer  29*346.  The  result- 
ing transpiration  times  for  hydrogen  and  carbonic  acid  are  0*4886  and  0*8288,  the 
time  of  air  being  1 ; or  multiplying  by  0*9  so  as  to  have  oxygen  1 — 


Hydrogen 0*4398 

Carbonic  acid 0*7459 


(3.)  Experiments  on  the  same  gases  were  repeated  at  a temperature  lower  by  10° 
Fahr.  The  times  of  air  were  902  and  902  seconds  ; of  hydrogen  442  and  444  seconds, 
and  of  carbonic  acid  742  and  742  seconds  ; thermometer  48°  Fahr,,  barometer  29*334. 
These  numbers  give  the  transpiration  times  1,  0*4911,  and  0*8226  for  air,  hydrogen 
and  carbonic  acid  respectively;  or,  with  oxygen  as  1, — 


Hydrogen 0*4419 

Carbonic  acid 0*7403 


Another  series  of  experiments  gave  for  carbonic  acid  the  transpiration  time  0*7432 
at  43°,  and  with  barometer  29*620.  It  will  be  observed  that  the  time  for  carbonic 
acid  now  begins  to  rise,  as  if  the  capillary  were  too  short  and  the  resistance  insuffi- 
cient to  neutralize  entirely  the  effect  of  effusion  in  that  gas.  The  times  however  of 
air,  hydrogen  and  carbonic  oxide  continue  normal. 

Experiments  were  made  with  the  same  capillary  reduced  to  6*4375  inches,  or  to 
one-eighth  of  its  original  length,  which  are  still  pretty  normal.  The  times  for  air 
were  670  and  670  seconds ; for  oxygen  746  and  745  seconds ; for  hydrogen  322  and 
322  seconds;  for  carbonic  acid  563  and  562  seconds,  with  thermometer  from  61°  to 
62°,  and  barometer  from  29*832  to  29*826.  These  give  the  transpiration  ratios, — 


Oxygen 1 

Air 0*8987 

Hydrogen 0*4319 

Carbonic  acid 0*7545 


For  shorter  lengths  of  the  capillary  K,  the  deviation  from  the  transpiration  rates 
becomes  very  notable.  I shall  supply  the  results  of  such  experiments,  as  they  illus- 
trate the  progress  of  the  deviation  from  the  transpiration  rates  in  a short  and  narrow 
capillary,  while  the  results  of  Table  II.  page  352,  show  the  progress  of  this  deviation 
in  a long  and  comparatively  wide  capillary. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


357 


Table  IV. — Transpiration  times  of  equal  volumes,  by  Capillary  K of  reduced 

lengths. 


Length  of  capillary. 

Oxygen. 

Air. 

Hydrogen. 

Carbonic  acid. 

4"3125  inches. 

1 

0-8985 

0-4250 

0-7770 

3*25 

1 

0-9035 

0-4176 

0-8059 

2-1875 

1 

0-9121 

0-3969 

0-8446 

1-125 

1 

0-9199 

0-3876 

0-9379 

The  absolute  times  for  air,  with  the  tubes  of  these  four  different  lengths,  were  473, 
370,  270  and  178  seconds;  the  temperature  varying  from  61°  to  63°,  and  the  baro- 
meter from  29‘562  to  29‘782  inches.  These  times,  it  will  be  observed,  do  not  become 
shorter,  exactly  as  the  length  of  the  tube  is  diminished,  but  less  rapidly  in  a very 
sensible  degree.  This  is  owing  to  the  interference  of  effusion. 

When  K was  4*3 125  inches  in  length  it  allowed  1 cubic  inch  of  air  to  pass  into  a 
vacuum,  under  the  pressure  of  1 atmosphere,  in  14  seconds;  or  it  discharged  4’3 
cubic  inches  of  air  per  minute.  The  discharge  by  the  capillary  H of  its  greatest 
length,  237’875  inches,  was  3*84  cubic  inches  per  minute.  These  two  tubes  therefore 
offer  a nearly  equal  resistance  to  the  passage  of  air  under  pressure.  On  comparing 
the  first  lines  of  Tables  II.  and  IV.,  however,  it  will  be  perceived  that  the  transpira- 
tion rates  of  hydrogen  and  carbonic  acid  are  sensibly  more  normal  for  the  long  than 
for  the  short  tube,  although  the  difference  is  not  great.  Still  it  appears  that  con- 
tracting the  diameter  of  a tube  does  not  produce  an  equally  available  resistance  as 
increasing  its  length.  In  other  respects  the  progress  of  the  deviation  from  the  normal 
transpiration  rates  of  the  same  gas,  and  of  different  gases  compared  together,  in  pro- 
portion as  the  resistance  diminishes,  appears  to  follow  the  same  law  in  the  short  as 
in  the  long  tube. 

While  discussing  the  properties  of  capillaries  of  different  dimensions,  I may  allude 
to  results  obtained  by  another  capillary  M,  of  the  same  extreme  length,  52’5  inches, 
and  of  nearly  the  same  resistance  as  K,  but  of  which  the  bore  was  cylindrical  and  not 
flat  like  that  of  K.  The  bore  of  M was  not  highly  uniform,  0'75  grain  of  mercury 
occupying  a length  of  the  cavity  which  varied  from  3'3  inches  at  one  end  to  2*3  inches 
at  the  other  end  of  the  tube.  It  was  employed  with  the  two-pint  aspirator-jar,  and 
the  fall  of  the  attaclied  barometer  was  observed  through  the  usual  range  from  28'5  to 
23’5  inches. 

(1.)  This  capillary  gave  the  transpiration  time  of  air  0'8997,  a highly  normal 
result. 

(2.)  The  times  for  air  in  two  experiments  being  1133  and  1132  seconds,  the  times 
of  carbonic  acid  were  913  and  911  seconds ; thermometer  68°  and  barometer  29  672. 

Transpiration  time  of  carbonic  acid . 07247 

In  a second  series  of  experiments  made  upon  the  same  gases,  the  times  of  air  being 
1104  and  1103  seconds,  the  times  of  carbonic  acid  were  892  and  892  seconds  ; and 

3 A 


MDCCCXLIX. 


358 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


of  hydrogen  534  and  534  seconds ; thermometer  58°‘5,  barometer  30'068.  These 
observations  give  the  transpiration  time  0’7275  for  carbonic  acid  and  0*4355  for 
hydrogen. 

(3.)  The  times  of  air  being  1109  and  1109  seconds,  the  times  of  carbonic  oxide 
were  1070  and  1070  seconds ; thermometer  67°*5,  barometer  29*808. 

Transpiration  time  of  carbonic  oxide 0*8683 

(4.)  The  times  of  air  being  1098  and  1099  seconds,  the  times  of  nitrogen  were 
1064  and  1062  seconds  ; thermometer  64°  to  65°,  barometer  29*904. 

Transpiration  time  of  nitrogen 0*8708 

(5.)  The  times  of  air  being  1084  and  1084  seconds,  the  times  of  hydrogen  were 
529  and  529  seconds ; thermometer  69°,  barometer  30*242  inches. 

Transpiration  time  of  hydrogen 0*4392 

In  the  present  experiments  with  hydrogen,  the  precautions  formerly  referred  to  for 
excluding  as  much  as  possible  the  access  of  a sensible  trace  of  air  from  the  water  of  the 
pneumatic  trough  were  put  in  practice.  The  times  obtained  for  this  and  all  the  other 
gases,  with  the  present  capillary,  will  be  observed  to  be  in  the  highest  degree  normal. 

(6.)  The  times  of  air  being  1095  and  1096  seconds,  those  of  olefiant  gas  were  641, 
641  and  641  seconds;  thermometer  69°,  barometer  30*102. 

Transpiration  time  of  olefiant  gas 0*5265 

The  time  formerly  obtained  for  the  same  gas  by  the  capillary  H of  small  resistance 
was  0*5186.  This  new  capillary  M was  afterwards  very  fully  employed  in  determining 
the  times  of  various  other  gases  and  vapours,  and  in  examining  the  influence  of 
pressure  and  temperature.  It  is  therefore  desirable  to  have  the  preceding  results 
which  this  capillary  gives  with  the  more  familiar  gases. 

(7.)  The  times  of  air  being  1120  and  1120  seconds,  those  of  protocarburetted  hy- 
drogen (the  gas  of  the  acetates)  were  684,  686  and  685  seconds  ; thermometer  61°*5, 
barometer  29*844. 

Transpiration  time  of  protocarburetted  hydrogen  . . . 0*5504 

The  time  0*5515  was  formerly  obtained  for  this  gas  by  capillary  E,  which  was  a 
long  tube  of  small  resistance,  very  like  capillary  IT. 

(8.)  The  times  of  air  being  1110  and  1111  seconds,  those  of  binoxide  of  nitrogen 
(NO2)  were  I070,  1070  and  IO7O  seconds;  thermometer  60°*5,  barometer  29*948  to 
29*782  inches. 

Transpiration  time  of  binoxide  of  nitrogen 0*8672 

This  result  is  in  accordance  with  the  conclusion  drawn  from  my  former  experi- 
ments upon  the  same  gas,  made  with  capillary  E,  namely,  that  the  time  of  nitric 
oxide  gas  coincides  with  that  of  nitrogen  and  carbonic  oxide. 

(9.)  Observations  were  made  with  the  same  capillary  M a little  reduced  in  length, 
namely,  to  50*5  inches,  and  with  a smaller  aspirator-jar ; the  range  observed  of  the 
attached  barometer  being  still  from  28*5  to  23*5  inches. 

It  now  gave  for  the  transpiration  time  of  air  0*8984. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


359 


The  times  for  air  being  460  and  459  seconds,  those  of  carbonic  acid  were  381  and 
381  seconds,  and  those  of  protoxide  of  nitrogen  (NO)  380  and  380  seconds;  ther- 
mometer 56°,  barometer  29  674. 

Transpiration  time  of  carbonic  acid 0’7448 

Transpiration  time  of  nitrous  oxide 0’7429 

results  which  illustrate  the  identity  in  transpiration  rate  of  these  two  gases,  which 
have  also  the  same  specific  gravity,  and  appear  to  correspond  remarkably  in  several 
other  physical  properties. 

The  difference  of  resistance  to  the  passage  of  a gas  offered  by  the  various  capillary 
tubes  already  used  is  certainly  considerable ; the  resistance  for  equal  lengths  of  tube 
being  in  round  numbers  fifty  times  greater  in  the  new  capillaries  K and  M,  than  in 
the  old  capillaries  E and  H.  But  large  as  is  this  range,  in  which  a remarkable  uni- 
formity of  transpiration  rate  of  the  gases  has  been  observed,  it  may  still  be  much 
extended.  The  capillaries  of  extreme  resistance  to  which  I shall  now  refer,  have 
great  advantages  over  the  others  already  described,  and  form  the  instruments  which 
I would  recommend  for  the  further  study  of  the  laws  of  transpiration. 

A thermometer  tube  of  the  finest  cylindrical  bore  being  selected,  a portion  of  about 
8 inches  is  taken,  and  being  progressively  heated  and  softened  at  the  lamp,  is  crushed 
up  into  a length  of  1 inch  or  less,  which  can  be  done  without  obliterating  the  cavity. 
The  cylindrical  mass  is  then,  while  still  soft,  drawn  out  into  a tube  of  ten  or  twelve 
times  its  original  length.  A thin  and  extremely  fine  capillary  tube  is  thus  obtained, 
which  is  much  more  regular  in  bore  than  might  be  expected  from  the  description  of 
its  preparation.  It  is  convenient  to  divide  the  rod,  which  is  less  in  diameter  than  a 
fine  straw,  into  lengths  of  4^  inches,  and  to  seal  immediately  the  open  extremities  of 
each  piece.  A transpiration  capillary  was  formed  of  a bundle  of  thirty  of  these  little 
rods,  which  were  placed  together  within  a short  glass  tube,  as  a case,  of  about  3^  inches 
in  length  and  half  an  inch  in  diameter;  so  that  the  ends  of  the  rods  projected  at  both 
ends  of  the  tube.  The  rods  were  fixed  within  the  tube  by  stucco,  which  was  dried  and 
afterwards,  while  warm,  soaked  in  melted  bees’-wax.  These  arrangements  being  en- 
tirely completed,  and  the  bundle  proved  to  be  impervious  to  air,  the  ends  of  the  rods 
were  now  broken  off,  and  the  tubes  thus  opened.  The  transpiration  instrument  P 
consisted  of  a bundle  of  thirty  such  capillary  tubes,  each  about  4 inches  in  length. 
Each  end  of  the  solid  cylinder  was  connected  with  a block-tin  tube  of  the  same  dia- 
meter by  means  of  a thick  vulcanized  caoutchouc  adopter.  One  of  these  tin  tubes 
was  connected  with  the  aspirator-jar,  or  left  open  to  the  air,  and  the  other  connected 
with  the  receiver  containing  the  gas  to  be  transpired. 

The  mode  of  conducting  the  experiment  was  further  changed.  Instead  of  drawing 
the  gas  through  the  capillaries  into  an  exhausted  receiver  or  vacuum,  the  gas  was 
compressed  in  a stout  metallic  receiver  or  condenser,  provided  with  a mercurial 
pressure  gauge,  by  which  the  elasticity  of  the  gas  within  could  be  observed*.  This 

* Phil.  Trans.  1846,  Plate  XXXIII.  fig.  3. 

3 A 2 


360 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


gauge  tube  was  a barometer  about  70  inches  in  length,  with  a vacuum  above  the 
mercury.  The  gas  was  allowed  to  escape  from  the  condenser  through  the  capillaries 
into  the  open  atmosphere,  or  into  a space  containing  air,  of  which  the  tension  was 
preserved  uniform,  and  which  formed  an  artificial  constant  atmosphere,  the  time 
being  noted  which  the  mercury  in  the  gauge  tube  of  the  condenser  took  to  fall 
through  a fixed  range  of  2,  4 or  10  inches,  according  to  the  degree  of  compression. 
The  available  capacity  of  the  condenser  was  about  72  cubic  inches. 

The  resistance  of  the  fine  capillary  tube  of  the  present  bundle  was  not  less  than 
400  times  greater  than  the  resistance  of  the  finest  tubes  hitherto  used,  namely  K and 
M,  the  comparison  being  made  between  equal  lengths  of  the  different  tubes. 

Experiments  with  eompound  Capillary  P. 

(1.)  Dry  oxygen  was  thrown  by  a syringe  into  the  condenser  till  the  pressure  in- 
dicated by  the  pressure  gauge  exceeded,  by  more  than  20  inches,  the  pressure  of  the 
external  atmosphere.  The  gas  was  then  allowed  to  escape  from  the  condenser 
through  the  capillaries  into  the  atmosphere,  and  the  times  noted  which  the  mercury 
of  the  pressure  gauge  took  to  fall  from  20  to  15,  10,  8,  6,  4 and  2 inches. 


Table  V. — Transpiration  of  Oxygen. 


Pressure  by  gauge  barometer. 

Experiment  I. 

Experiment  II. 

Experiment  III. 

inches. 

// 

// 

// 

20 

0 

0 

0 

15 

241 

240 

241 

10 

352 

353 

352 

8 

202 

202 

200 

6 

266 

266 

265 

4 

379 

382 

378 

2 

653 

650 

647 

From  20  to  2 inches  

2093 

2093 

2083 

(2.)  A similar  series  of  experiments  was  made  on  the  transpiration  of  compressed 
air,  of  which  the  results  are  as  follows : — 


Table  VI. — Transpiration  of  Air. 


Pressure  by  gauge  barometer. 

Experiment  I. 

Experiment  11. 

inches. 

// 

// 

20 

0 

0 

15 

217 

217 

10 

316 

316 

8 

181 

181 

6 

239 

238 

4 

400 

400 

2 

524 

524 

From  20  to  2 inches  

1877 

1876 

Both  these  last  series  and  the  series  which  follows  on  carbonic  acid  were  made 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


361 


with  the  thermometer  at  66°,  and  barometer  from  30' 144  to  30' 112  inches.  Means 
were  taken  to  preserve  the  temperature  constant  during  this  and  similar  experiments, 
by  immersing  the  condenser,  and  also  the  capillary,  in  vessels  of  water  of  which  the 
temperature  was  watched  by  an  assistant  and  preserved  uniform. 

The  average  times  of  falling  from  a pressure  of  20  to  10  inches  are  for  oxygen  and 
air,  593  and  533  seconds  respectively;  numbers  which  are  in  the  proportion  of  1 to 
0’8988.  The  average  times  from  10  to  6 inches  are  467  and  419'5  seconds;  that  is, 
as  1 to  0'8983 : from  6 to  2 inches,  1030  inches  and  924  seconds;  that  is,  as  1 to 
0-8971.  The  average  whole  time  of  escape,  or  during  the  fall  from  20  to  2 inches, 
is  2088  seconds  for  oxygen  and  1876-5  seconds  for  air,  numbers  which  are  in  the 
proportion  of  1 to  0-8987. 

The  transpiration  time  of  air  is  therefore  highly  uniform  under  different  pressures, 
and  approaches  closely  to  its  theoretical  density  or  time  0-9010. 

(3.)  The  parallel  experiments  on  compressed  carbonic  acid  gas  escaping  into  air 
are  contained  in  the  following  Table  : — 


Table  VII. — Transpiration  of  Carbonic  Acid. 


Pressure  by  gauge  barometer. 

Experiment  I. 

Experiment  11. 

inches. 

// 

// 

20 

0 

0 

15 

178 

178 

10 

260 

260 

8 

148 

148 

6 

195 

195 

4 

278 

279 

2 

475 

474 

From  20  to  3 inches  

1534 

1534 

Comparing  these  times  with  the  times  of  oxygen,  we  obtain  the  following  results: — 
Transpiration  times  of  Carbonic  Acid. 


From  20  to  10  inches  pressure 0-7384 

From  10  to  6 inches  pressure 0-7345 

From  6 to  2 inches  pressure 0-7311 

From  20  to  2 inches  (average) 0-7346 


The  times  for  carbonic  acid  have  not  the  nearly  perfect  uniformity  of  those  of  air, 
for  different  pressures,  but  still  their  relation  is  close,  particularly  in  the  lower  part 
of  the  scale  where  times  are  long  and  can  be  best  observed.  The  time  from  4 to  2 
inches  is  474-5  seconds  with  carbonic  acid  and  650  seconds  with  oxygen,  which  give 
as  the  transpiration  time  of  carbonic  acid  0-7300. 

It  will  be  observed  how  nearly  the  times  for  this  gas  approach  0-7272,  the  reci- 
procal of  its  density. 

In  a second  series  of  experiments  made  upon  carbonic  acid,  at  the  same  time  as 


362 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


those  which  follow  upon  hydrogen,  the  transpiration  times  which  were  obtained  foi 
the  three  portions  of  the  scale  already  described  were  0*7344,  0*7388  and  0*7294, 
which  approach  the  speculative  number  for  carbonic  acid  quite  as  closely  as  the 
experiments  previously  detailed. 

(4.)  The  hydrogen  was  prepared  (as  was  always  the  case)  from  zinc  which  con- 
tained no  arsenic,  and  was  passed  through  a wash  bottle  containing  oxide  of  lead 
dissolved  in  caustic  soda,  and  dried  by  passing  over  asbestos  moistened  with  oil  of 
vitriol.  The  thermometer  was  67°  and  the  barometer  29*506  inches. 


Table  VIII. — Transpiration  of  Air  and  Hydrogen. 


Pressure  by  gauge  barometer. 

Air. 

Hydrogen. 

Experiment  I. 

Experiment  II. 

Experiment  I. 

Experiment  II. 

inches. 

//■ 

// 

20 

0 

0 

0 

0 

15 

221 

221 

107 

107 

10 

328 

328 

158 

159 

8 

188 

185 

92 

91 

6 

251 

251 

121 

121 

4 

422 

423 

176 

178 

2 

579 

580 

310 

308 

From  20  to  2 inches 

1989 

1988 

964 

964 

The  results  calculated  from  the  means  of  these  experiments  are  as  follows,  the 
transpiration  time  of  air  being  taken  as  0*9 : — 


Transpiration  times  of  Hydrogen. 


Air  =1. 

Oxygen  =1. 

From  20  to  10  inches  ... 
From  10  to  6 inches  ... 
From  6 to  2 inches  ... 
From  20  to  2 inches  ... 

0-4845 

0-4866 

0-4859 

0-4867 

0-4352 

0-4371 

0-4364 

0-4371 

The  experimental  times  for  hydrogen  vary  only  in  the  smallest  degree  at  different 
pressures,  and  almost  coincide  with  the  theoretical  time  for  this  gas,  0*4375,  which 
is  one-half  of  the  time  of  nitrogen  and  7-16ths  of  that  of  oxygen.  This  result  is  so 
important  that  I shall  make  no  apology  for  presenting  another  series  of  experiments 
in  which  hydrogen  was  compared  directly  with  oxygen. 

The  temperature  during  the  following  experiments  was  67°,  and  the  barometer 
29*420  to  29*458  inches. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


363 


Table  IX. — Transpiration  of  Hydrogen  and  Oxygen. 


Pressure  by  gauge  barometer. 

Hydrogen. 

Oxygen. 

Experiment  I. 

Experiment  II. 

Experiment  I. 

Experiment  II. 

inches. 

// 

// 

20 

0 

0 

0 

0 

15 

107 

107 

242 

246 

10 

158 

158 

263 

260 

8 

91 

90  . 

208 

208 

6 

120 

120 

274 

274 

4 

174 

175 

396 

398 

2 

298 

299 

687 

687 

From  20  to  2 inches 

948 

949 

2170 

2173 

By  dividing  the  means  of  the  hydrogen  numbers  by  the  means  of  the  oxygen  num- 
bers, as  usual,  we  obtain  the  following  results : — 


Transpiration  times  of  Hydrogen. 

From  20  to  10  inches 0‘4380 

From  10  to  6 inches 0*4367 

From  6 to  2 inches 0*4363 

From  20  to  2 inches 0*4370 

These  results  are  therefore  in  entire  concordance  with  the  preceding  series,  and 
with  0*4375  as  the  transpiration  time  of  hydrogen  gas. 

(5.)  A series  of  experiments  were  made  on  the  transpiration  of  carbonic  oxide  in 
conjunction  with  those  last  related. 


Table  X. — Transpiration  of  Carbonic  Oxide. 


Pressure  by  gauge  barometer 
above  1 atmosphere. 

Experiment  I. 

Experiment  II. 

inches. 

// 

it 

20 

0 

0 

15 

213 

213 

10 

315 

315 

8 

181 

181 

6 

241 

241 

4 

346 

346 

From  20  to  4 inches 

1296 

1296 

The  experiments  on  this  gas  are  only  given  from  20  to  4 inches,  some  error  of 
observation  having  occurred  in  taking  the  times  at  2 inches.  Comparing  them  with 
the  last  experiments  on  oxygen,  we  obtain  the  following  results : — 


364 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


Transpiration  time  of  Carbonic  Oxide. 


From  20  to  10  inches 0'8727 

From  10  to  6 inches 0’8755 

From  6 to  4 inches 0*87 15 

From  20  to  4 inches 0‘8737 


The  transpiration  time  of  carbonic  oxide  thus  appears  to  be  uniform  at  different 
pressures,  and  to  correspond  very  closely  with  its  theoretical  density,  0‘8750.  The 
transpiration  times  of  this  gas  and  of  nitrogen  no  doubt  correspond  with  each  other 
as  closely  as  their  densities,  and  are  both  double  the  time  of  hydrogen. 

It  thus  appears  that  the  results  obtained  by  means  of  the  sheaf  of  capillaries  of 
extreme  resistance  are  the  most  uniform  of  all,  and  that  they  afford  a confirmation  of 
the  conclusions  drawn  from  the  results  of  former  capillaries  of  greatly  less  resistance, 
which  it  is  difficult  to  withstand.  These  conclusions  are,  that  the  times  of  passage 
through  capillary  tubes,  of  equal  volumes  of  different  gases  under  the  same  pressure, 
approximate  to,  and  have  their  limit  in,  the  following  numbers  : — 


Transpiration  times. 

Oxygen 1‘ 

Air 0‘9010 

Nitrogen  and  carbonic  oxide  . . . 0’8750 

Hydrogen 0'4375 

Carbonic  acid 0‘7272 


The  times  of  oxygen,  nitrogen,  carbonic  oxide  and  air,  are  directly  as  their  densi- 
ties, or  equal  weights  of  these  gases  pass  in  equal  times.  Hydrogen  passes  in  half  the 
time  of  nitrogen,  or  twice  as  rapidly  for  equal  volumes.  The  result  for  carbonic  acid 
appears  at  first  anomalous.  It  is,  that  the  transpiration  time  of  this  gas  is  inversely 
proportional  to  its  density,  when  compared  with  oxygen.  It  is  to  be  remembered, 
however,  that  carbonic  acid  is  a compound  gas,  containing  an  equal  volume  of  oxygen. 
The  second  constituent  carbon  which  increases  the  weight  of  the  gas,  appears  to  give 
additional  velocity  to  the  oxygen  in  the  same  manner  and  to  the  same  extent  as 
increased  density  from  pressure,  or  from  cold  (as  I believe  I shall  be  able  to  show), 
increases  the  transpiration  velocity  of  pure  oxygen  itself.  A result  of  this  kind  shows 
at  once  the  important  chemical  bearing  of  gaseous  transpirability,  and  that  it  emulates 
a place  in  science  with  the  doetrines  of  gaseous  densities  and  combining  volumes. 

The  circumstance  that  the  transpiration  time  of  hydrogen  is  one-half  of  that  of  nitro- 
gen, indieates  that  the  relations  of  transpirability  are  even  more  simple  in  their  ex- 
pression than  the  relations  of  density  among  gases.  In  support  of  the  same  assertion 
may  be  addueed  the  additional  fact,  that  binoxide  of  nitrogen,  although  differing  in 
density,  appears  to  have  the  same  transpiration  time  as  nitrogen.  Protoxide  of 
nitrogen  and  carbonic  acid  have  one  transpiration  time,  so  have  nitrogen  and 
carbonic  oxide,  as  each  pair  has  a common  density. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


365 


II.  TRANSPIRATION  OF  VARIOUS  GASES  AND  VAPOURS.  , ,,,,  , 

1.  Protocarburetted  Hydrogen,  CHg. 

It  is  necessary  to  mention  how  this  gas  was  prepared,  as  it  is  one,  like  olefiant  gas, 
of  which  we  are  never  quite  certain  of  the  absolute  purity.  Six  hundred  grains  of 
dried  acetate  of  soda,  the  same  weight  of  fused  hydrate  of  potash,  and  nine  hundred 
grains  of  unslaked  quick-lime,  all  in  fine  powder,  were  well-mixed  in  a coated  Flo- 
rence flask  used  as  a retort,  and  the  gas  brought  off  by  heat.  The  last  portions  of 
gas  were  rejected.  The  hydrate  of  baryta  never,  in  my  hands,  gave  so  pure  a gas, 
when  substituted  for  the  hydrate  of  potash.  Free  hydrogen,  the  usual  impurity  in 
this  gas,  I have  formerly  shown  to  have  scarcely  any  effect  upon  the  rate  of  carburetted 
hydrogen,  when  present  only  to  the  extent  of  a few  per  cent. 

The  old  experiments  with  the  long  20  feet  capillaries  E and  H,  of  small  resistance, 
agreed  remarkably  in  the  transpiration  time  0‘5515  for  this  gas.  With  capillary  M, 
52*5  inches  in  length,  and  transpiring  into  a vacuum,  I obtained  684,  686,  685  seconds 
as  the  time  for  this  gas,  against  1 120  and  1120  seconds  for  air ; thermometer  62°,  and 
barometer  29‘844  inches.  This  gives  0*5504  for  carburetted  hydrogen  for  a capillary 
of  great  resistance.  This  gas,  in  a state  of  compression,  was  transpired  by  the  same 
capillary  into  air  as  in  the  experiments  to  follow  on  olefiant  gas.  The  results,  with- 
out details,  were  as  follows  : thermometer  64°,  barometer  30*050  to  30*074. 

Transpiration  of  Protocarburetted  Hydrogen  (into  air)  by  Capillary  M, 

52*5  inches  in  length. 


Air  =1. 

Oxygen  =1. 

From  20  to  10  inches  ... 
From  10  to  6 inches  ... 
From  6 to  4 inches  ... 
From  4 to  2 inches  ... 
From  2 to  1 inch  

0-6304 

0-6254 

0-6269 

0-6335 

0-6349 

0-5495 

0-5490 

0-5515 

0-5525 

0-5607 

From  10  to  1 inch  

0-6321 

0-5541 

The  transpiration  of  this  gas  appears  highly  uniform  at  different  pressures.  Ex- 
cluding the  two  observations  at  the  extremes  of  the  scale,  the  mean  result  is — 
Transpiration  time  of  protocarburetted  hydrogen  . . . 0*5510. 

A repetition  of  the  last  experiments  gave  a slightly  different  series  of  numbers, 
namely,  0*5583,  0*5497,  0*5541,  0*5523,  0*5549;  showing  that  the  slight  departure 
from  uniformity  among  the  results  at  different  pressures  before  observed  is  of  an  ac- 
cidental nature,  and  does  not  follow  any  fixed  law.  The  mean  of  the  three  preferable 
new  observations  gives  0*5510,  or  precisely  the  same  result  as  the  former  series. 

This  number  for  protocarburetted  hydrogen  closely  approaches  0*5536,  which  is 
seven  elevenths,  or  of  0*870,  the  time  of  nitrogen.  The  numerical  relation  may  be 

3 B 


MDCCCXLIX. 


366 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


accidental,  but  the  circumstances  that  14,  which  expresses  the  density  and  time  of 
nitrogen,  is  double  the  time  of  hydrogen  7?  and  that  22  expresses  the  density  of  car- 
bonic acid,  to  which  carburetted  hydrogen  presents  a certain  chemical  analogy  in 
composition,  appear  to  afford  some  physical  basis  for  it. 

The  time  of  protocarburetted  hydrogen  may  also  be  stated  to  be  one-fourth  more 
than  0’44,  the  usually  observed  time  of  hydrogen  itself. 

2.  Olejiant  Gas. 

The  circumstance  that  olefiant  gas  has  the  same  theoretical  density  as  nitrogen  and 
carbonic  oxide,  and  yet  differs  greatly  from  these  gases  in  transpirability,  gives  a 
peculiar  interest  to  the  transpiration  time  of  that  gas.  The  olefiant  gas  used  was 
always  prepared  in  the  following  manner : — Fifty-four  volumes  (water  ounce  mea- 
sures) of  oil  of  vitriol  were  mixed  with  twenty- eight  volumes  of  water  and  cooled, 
which  gave  an  acid  of  specific  gravity  T600.  To  this  twenty-four  volumes  of  alcohol, 
generally  of  specific  gravity  0*84,  were  added,  and  the  mixture  allowed  to  stand  over 
night.  The  gas  was  evolved  by  a heat  of  about  320°  Fahr.,  and  transmitted,  for  the 
purpose  of  purifying  it  through  five  wash-bottles,  the  first  containing  potash,  the 
second  water,  the  third  oil  of  vitriol,  the  fourth  potash,  and  the  fifth  oil  of  vitriol. 
The  process  yielded  a good  deal  of  ether,  with  a large  product  of  gas. 

My  old  experiments,  with  capillary  H of  great  length  but  small  resistance,  gave 
0'5186  as  the  transpiration  time  of  this  gas.  I subsequently  obtained  the  number 
0’5241  with  capillary  K of  8‘75  inches  in  length,  and  also  of  small  resistance.  With 
capillary  M of  52’5  inches  in  length,  and  of  considerable  resistance,  I also  obtained 
the  number  0‘5265  ; the  gas  in  all  these  cases  passing  into  the  nearly  vacqous  jar 
under  the  pressure  of  the  atmosphere.  But  the  most  complete  series  of  experiments 
was  made  upon  this  gas  in  a compressed  state,  in  the  globular  digester  of  72  cubic 
inches  in  capacity,  the  gas  escaping  into  air.  The  capillary  M was  employed  of  50*5 
inches  in  length. 


Table  XI. — Transpiration  of  Olefiant  Gas  and  Air  (into  air). 


Height  of  gauge  barometer 
above  1 atmosphere. 

Air. 

Olefiant  gas. 

Experiment  I. 

Experiment  11. 

Experiment  I. 

Experiment  II. 

inches. 

// 

// 

20 

0 

0 

0 

0 

15 

198 

196 

116 

116 

10 

285 

285 

165 

165 

8 

l6l 

l6l 

93 

93 

6 

213 

213 

120 

121 

4 

307 

307 

174 

174 

2 

530 

530 

301 

301 

1 

529 

530 

299 

300 

The  fall  from  20  to  10  inches  requires  482  seconds  in  air  and  281  in  olefiant  gas, 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


367 


numbers  which  are  as  1 to  0‘5830.  The  ratios  or  transpiration  times  appear  in  the 
following-  Table  ; — 


Transpiration  times  of  Olefiant  Gas. 


Air  = 1. 

Oxygen  = 1. 

From  20  to  10  inches  ... 
From  10  to  6 inches  ... 
From  6 to  4 inches  ... 
From  4 to  2 inches  ... 
From  2 to  1 inch  

0-5830 

0-5709 

0-5667 

0-5679 

0-5656 

0-5212 

0-5103 

0-5066 

0-5085 

0-5081 

In  reducing  these  results  from  the  scale  of  air  to  that  of  oxygen,  the  following 
coefficients  were  used  as  the  transpiration  times  of  air.  They  were  obtained  by 
experiment.  From  20  to  10  inches  air  =0'8941  ; from  10  to  6 inches  0'8939  ; from 
6 to  4 inches  0*8941  ; from  4 to  2 inches  0*8967 ; from  2 to  1 inch  0*8967 ; the  air 
coefficients  being  all  sensibly  lower  than  0*9. 

The  transpiration  time  of  this  gas  appears  to  vary  at  different  parts  of  the  scale  of 
pressure  fully  more  than  carbonic  acid  does.  This  may  arise,  as  with  carbonic  acid, 
from  the  extreme  difference  which  exists  between  the  effusion  and  transpiration  rate 
of  the  gas. 

Hence  an  unusually  great  resistance,  which  is  only  met  in  the  lower  part  of  the 
scale,  is  required  to  eliminate  completely  the  influence  of  effusion  upon  the  transpira- 
tion rate.  The  smallest  transpiration  time  observed  above  for  olefiant  gas  is  0*5066, 
which  certainly  does  not  differ  much  from  0*5,  or  half  the  time  of  oxygen.  But  it 
would  be  premature  to  adopt  that  relation  definitively,  as  a number  nearer  to  0*51 
would  be  the  more  legitimate  expression  of  the  whole  results. 

In  a second  series  of  experiments  conducted  precisely  in  the  same  manner,  with 
the  thermometer  at  67°  and  the  barometer  30*020  to  30*034,  the  results  were  as 
follows : — 


Transpiration  time  of  Olefiant  Gas  (into  air). 


Air  =1. 

Oxygen  =1. 

From  20  to  10  inches  ... 
From  8 to  6 inches  ... 
From  6 to  4 inches  ... 
From  4 to  2 inches  ... 
From  2 to  1 inch  

0-5855 

0-5745 

0-5663 

0-5642 

0-5647 

0-5234 

0-5136 

0-5062 

0-5043 

0-5048 

From  20  to  1 inch  

0-5669 

0-5068 

The  same  remarks  apply  to  the  last  as  to  the  immediately  preceding  series  of  ex- 
periments ; the  two  series  agreeing  together  most  closely.  The  mean  of  the  three 
times  observed  in  the  range  of  pressure  from  6 inches  to  1 inch  is  0*5051  ; and  the 
least  transpiration  time  observed  for  olefiant  gas  (from  4 to  2 inches  pressure)  is 
0*5043. 


3 B 2 


368 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


To  contrast  the  two  different  methods  of  transpiration,  that  of  condensed  gas 
escaping  into  air,  and  of  gas  under  the  usual  pressure  of  the  atmosphere  only,  or 
under  a less  pressure,  passing  into  a vacuum,  a third  series  of  experiments  was  made 
upon  olefiant  gas.  The  same  globular  condenser  being  full  of  olefiant  gas,  of 
the  tension  of  the  atmosphere  at  the  time,  which  was  30*034  inches,  the  gas  was 
allowed  to  escape  through  the  capillary  M into  the  receiver  of  an  air-pump  kept 
vacuous  by  constant  exhaustion.  It  was  thus  transpired  into  a vacuum  but  with  con- 
stantly diminishing  force,  for  the  force  with  which  the  gas  was  sent  out  would 
diminish  of  course  in  proportion  as  the  globular  receiver  was  emptied.  The  baro- 
metric gauge  tube  of  this  receiver,  being  closed  at  top  and  vacuous,  gave  the  neces- 
sary means  of  observing  the  progress  of  the  escape  of  the  gas  as  it  was  transpired 
into  the  vacuum.  In  the  following  table  of  observations,  the  first  column  of  the 
height  of  the  gauge  barometer  is  its  absolute  height,  and  expresses  the  whole  tension 
or  elasticity  of  the  gas.  Thermometer  67°. 


Table  XII. — Transpiration  of  Olefiant  Gas. 


Height  of  gauge  barometer. 

Olefiant  gas. 

Air. 

Experiment  I. 

Experiment  II. 

Experiment  I. 

Experiment  II. 

inches. 

O 

O 

O 

0 

30 

0 

0 

0 

0 

25 

191 

191 

327 

327 

20 

276 

276 

480 

480 

18 

152 

152 

267 

267 

16 

187 

187 

316 

315 

14 

242 

242 

432 

430 

12 

318 

319 

558 

558 

10 

446 

446 

773 

771 

From  20  to  10 

1347 

1345 

2346 

2341 

The  results  are  sensibly  different  in  one  part  of  the  scale  from  those  obtained  by 
the  other  method  of  transpiration,  as  will  be  seen  by  comparing  the  following  state- 
ment with  the  former  results. 


Transpiration  of  Olefiant  Gas  (into  a vacuum). 


Air  =1. 

Oxygen  =1. 

From  30  to  20  inches  ... 
From  20  to  1 6 inches  ... 
From  16  to  14  inches  ... 
From  14  to  12  inches  ... 
From  12  to  10  inches  ... 

0-5791 

0-5476 

0-5615 

0-5717 

0-5777 

0-5212 

0-4928 

0-5054 

0-5145 

0-5199 

From  30  to  10  inches  ... 

0-5743 

0-5169 

The  time  seems  to  increase  as  we  descend  in  the  scale,  or  with  the  resistance, 
with  the  exception  of  the  first  observation,  which  probably  is  made  to  deviate  from 
the  general  progression  by  some  accidental  cause.  It  would  probably  be  more  cor- 


PROFESSOR  GRAHAM  ON  MOTION  OF  GASES. 


r«)9 

rect  to  take  the  first  and  second  times  together,  or  the  whole  fall  from  30  to  16  inches, 
which  gives — 


Air  =1. 

Oxygen  =1. 

Transpiration  time  of  olefiant  gas 

0-5659 

0-5093 

The  times  from  30  to  14  inches,  0'5093  and  0*5054,  will  thus  closely  approach  to 
the  average  time  obtained  by  the  other  method.  But  under  14  inches  of  pressure, 
where  the  transpiration  becomes  extremely  slow  as  the  resistance  is  greatly  increased, 
the  times  rise  to  0*5145  and  0*5199.  In  the  present  state  of  our  knowledge  respecting 
transpiration,  it  is  difficult  to  decide  upon  the  comparative  value  of  these  results,  and 
to  say  which  represents  best  the  true  transpiration  time  of  olefiant  gas.  An  unex- 
plained variation  of  1|^  per  cent,  in  the  transpiration  time  of  this  gas  must  at  present 
be  admitted,  which  is  a much  greater  latitude  in  the  results  than  was  observed  with 
nitrogen,  hydrogen,  protocarburetted  hydrogen,  or  even  with  carbonic  acid. 

3.  Ammonia. 

This  gas  is  supposed  to  have  certain  chemical  relations  to  olefiant  gas,  although 
differing  very  widely  from  the  latter  in  its  physical  properties.  The  theoretical 
density  of  ammonia  is  8*5,  that  of  oxygen  being  16;  or  539*6  to  oxygen  1000.  It  is 
therefore  considerably  lighter  than  olefiant  gas ; it  is  also  liquefied  by  pressure,  and 
highly  soluble  in  water,  which  the  latter  is  not. 

This  gas  was  always  dried  by  passing  over  fragments  of  fused  hydrate  of  potash. 
The  mode  of  operating  with  gases  like  ammonia,  which  cannot  be  retained  over 
water,  found  most  convenient  was  to  maintain  a continued  and  copious  evolution  of 
the  gas  during  the  whole  period  of  the  transpiration  experiments,  conveying  the  gas 
into  an  empty  bottle  in  the  first  instance,  of  which  the  cork  was  perforated  by  three 
tubes.  By  one  of  these  tubes  the  gas  entered  this  bottle,  by  another  the  portion  of 
gas  required  for  transpiration  was  condueted  to  the  capillary,  and  the  third,  which 
was  bent  downwards  and  its  extremity  allowed  to  dip  a line  or  two  into  a little  cup 
of  water,  formed  a waste-pipe  or  relief  tube,  by  which  the  excess  of  gas  evolved 
escaped  into  the  atmosphere.  The  same  method  was  equally  applicable  to  hydrogen, 
carbonic  acid,  chlorine,  &c.,  and  does  away  with  the  necessity  of  collecting  these 
gases  over  water,  and  so  exposing  them  to  contamination. 

(1.)  This  gas  was  transpired  by  capillary  K,  8*5  inches  in  length,  into  the  six-pint 
aspirator-jar  upon  the  plate  of  the  air-pump,  through  the  usual  range  of  28*5  to  23*5 
inches  on  the  gauge  barometer ; thermometer  54°,  barometer  29*772  inches.  In  two 
experiments  with  air  the  times  were  982  and  981  seconds ; in  three  experiments  with 
ammonia  546,  546,  and  546  seconds.  This  gives  0*5563  for  the  time  of  ammonia 
referred  to  air,  or  multiplying  this  number  by  0*9  to  reduce  it  to  the  scale  of 
oxygen  -=  1 , we  have, — 

Transpiration  time  of  ammonia  . 


0*5007 


370 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


The  conclusion  suggested  by  this  result,  that  the  transpiration  time  of  ammonia  is 
one-half  that  of  oxygen,  is  not  supported  so  strongly  by  capillary  tubes  of  great 
resistance. 

(2.)  Experiments  were  made  with  capillary  M,  52-5  inches  in  length  ; thermometer 
61°,  barometer  29*900  to  29*908  inches.  The  time  of  air  being  1110,  1111,  and  1111 
seconds,  that  of  ammonia  was  632,  632,  and  632  seconds;  as  1 to  0*5688.  Referred 
to  oxygen,  the  result  becomes — 

Transpiration  time  of  ammonia 0*5119 

A second  series  of  experiments  with  the  same  capillary,  thermometer  61°*5  and 
barometer  29*800  to  29*810,  gave  a very  similar  result,  namely,  1121  and  1123  seconds 
for  air,  and  640  and  640  seconds  for  ammonia;  numbers  which  are  as  1 to  0*5704, 
and  give, — 

Transpiration  time  of  ammonia 0*5134 

(3.)  A third  series  of  experiments  was  made  upon  this  gas  under  pressure  in  the 
globular  digester,  and  escaping  into  air  by  the  sheaf  of  thirty  capillary  tubes  P.  The 
thermometer  was  at  60°,  and  the  barometer  from  29*888  to  29*918  inches  during  the 
experiments. 


Table  XIII. — Transpiration  of  Ammonia  (into  air). 


Height  of  gauge  barometer 
above  1 atmosphere. 

Air. 

Ammonia. 

Experiment  I. 

Experiment  II. 

Experiment  I. 

Experiment  II. 

inches. 

// 

// 

20 

0 

0 

0 

0 

15 

218 

217 

124 

124 

10 

319 

321 

182 

182 

8 

186 

186 

107 

106 

6 

243 

243 

138 

139 

4 

354 

355 

201 

201 

2 

621 

621 

350 

357 

1 

635 

645 

352 

350 

From  20  inches  to  1 

2576 

2588 

1454 

1459 

The  observation  at  1 inch,  or  even  at  2 inches,  does  not  admit  of  the  same  precision 
as  in  the  higher  parts  of  the  scale,  owing  to  the  slowness  with  which  the  mercury 
descends,  leaving  a doubtful  period  of  3 or  4 seconds  which  the  mercury  is  in  passing 
the  mark.  The  experiments  at  different  parts  of  the  scale,  it  will  be  seen,  concur  in 
giving  nearly  the  same  result,  except  for  the  last  inch,  where  this  uncertainty  appears 
to  have  occasioned  a sensible  error. 

Transpiration  times  of  Ammonia  at  different  pressures. 


Air  =1. 

Oxygen  =1. 

From  20  to  10  inches  ... 
From  10  to  6 inches  ... 
From  6 to  2 inches  ... 
From  2 to  1 inch  

0-5693 

0-5711 

0-5684 

0-5484 

0-5112 

0-5128 

0-5104 

0-4936 

PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


371 


The  common  multiplier  by  which  the  numbers  of  the  oxygen  scale  have  been  de- 
rived from  the  air  scale  is  0'898.  Excluding  the  last  result,  we  have,  on  the  oxygen 
scale, — 

The  mean  transpiration  time  of  ammonia 0*51 15 

This  time  for  ammonia  corresponds  very  closely  with  the  results  previously  obtained 
by  the  long  single  capillary  M,  namely,  0'5119  and  0‘5134.  The  coincidence  in  the 
rates  of  M with  those  of  the  compound  capillary,  for  a liquefiable  gas  like  ammonia, 
is  a circumstance  of  considerable  importance,  as  a large  proportion  of  the  experiments 
which  1 have  to  detail  on  gases  of  this  class  were  made  with  the  first-named  only  of 
these  capillaries.  The  number  for  ammonia  certainly  approaches  to  0‘5076  and 
0*5093,  the  mean  transpiration-times  of  olefiant  gas,  but  cannot  be  said  to  coincide 
with  them,  and  is  of  course  somewhat  more  distant  from  0*5. 

4.  Cyanogen. 

This  gas  was  prepared  from  well-crystallized  and  perfectly  dry  cyanide  of  mercury. 
To  secure  its  purity  the  gas  was  besides  passed  over  red  oxide  of  mercury  and  chlo- 
ride of  calcium.  The  gas  was  conveyed  to  the  capillary  in  the  same  manner  as  am- 
monia. The  capillary  employed  was  the  long  tube  M,  of  52*5  inches,  the  gas  under 
the  pressure  of  the  atmosphere  being  drawn  into  the  two-pint  aspirator-jar,  exhausted 
as  usual  upon  the  plate  of  an  air-pump.  Thermometer  60°,  barometer  from  29*910 
to  29*864  inches. 

The  experiments  were  made  in  the  following  order: — air,  1113,  1114  seconds; 
cyanogen,  626,  628,  627  and  627  seconds;  air,  1117,  1117  seconds.  The  slight  in- 
crease of  the  air-time  in  the  last-made  experiments  is  undoubtedly  owing  to  the  fall 
of  the  barometer.  The  ratio  of  the  cyanogen  to  the  first  air-time  is  0*5631,  and  to 
the  second  air-tirne  0*5613;  or  0*5068  and  0*5052,  with  oxygen  =1.  The  mean  of 
the  two  results  gives, — 

Transpiration  time  of  cyanogen  .........  0*5060 

The  transpiration  time  of  cyanogen  may  therefore  be  confounded  with  that  of  ole- 
fiant gas,  0*5076,  transpired  in  the  same  manner,  although  the  densities  of  these  two 
gases  differ  so  widely  as  14  to  26  (oxygen  =16). 

5.  Hydrocyanic  Acid. 

A considerable  quantity  of  the  absolute  acid  was  prepared  by  distilling  15  ounces 
of  crystallized  ferrocyanide  of  potassium  with  9 ounces  of  oil  of  vitriol  diluted  by  an 
equal  weight  of  water.  The  liquid  acid  was  afterwards  dried  by  digesting  it  over 
pounded  chloride  of  calcium. 

As  hydrocyanic  acid  is  liquid  at  the  usual  temperature,  air  or  hydrogen  saturated 
with  the  vapour  of  the  acid  was  transpired  instead  of  the  pure  substance  itself.  The 
air  or  hydrogen  was  made  to  stream  through  the  liquid  acid  contained  in  a wash- 
bottle  to  a depth  of  2 inches,  and  surrounded  with  water  to  which  a slight  heat  was 
applied,  so  as  to  maintain  the  water  and  wash-bottle  at  the  fixed  temperature  of  the 


372 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


experiment,  and  to  compensate  for  the  cold  of  evaporation.  The  tension  of  the 
hydrocyanic  acid  vapour  at  59°,  the  temperature  of  the  experiments,  was  found  to  be 
1 8'8  inches.  The  composition  of  the  mixed  vapour  operated  upon  was — 

Volumes. 

Air  or  hydrogen 10‘8  or  36*48 

Hydrocyanic  acid  . . . . 18*8  or  63*52 

29*6  100*00 

The  vapour  was  transpired  under  the  pressure  of  the  atmosphere  by  the  capillary 
M,  52*5  inches  in  length,  into  the  two-pint  aspirator-jar,  through  the  usual  range 
(28*5  to  23*5  inches)  of  the  attached  barometer.  Thermometer  59°,  barometer  29*5 18 
to  29*644  inches. 

The  transpiration  time  of  air  was  1138  and  1138  seconds  in  two  experiments.  The 
time  of  air  impregnated  with  hydrocyanic  acid  was  80/,  809,  808,  808  seconds,  in 
four  experiments  ; which  gives  to  the  latter  the  ratio  of  0*7100.  Multiplying  by  0*9, 
we  obtain — 

Transpiration  time  of  air  saturated  with  hydrocyanic  acid  vapour  at  59°  0*6390. 

It  is  obvious  therefore  that  hydrocyanic  acid  vapour  is  greatly  more  transpirable 
than  air.  The  theoretical  density  of  hydrocyanic  acid  vapour  is  13*5,  the  density  of 
oxygen  being  16. 

Hydrogen  gas  equally  impregnated  with  hydrocyanic  acid  vapour  was  transpired 
in  the  times  579  and  579  seconds,  which  gives  the  ratio  to  air  of  0*5088.  Multi- 
plying by  0*9,  we  obtain — 

Transpiration  time  of  hydrogen  saturated  with  hydrocyanic  acid  vapour  at  59°, 
0*4579. 

Judging  from  our  former  results  on  mixtures  of  hydrogen  with  denser  gases,  in 
which  it  appeared  that  the  rate  of  the  mixture  never  deviated  far  from  that  of  the  dense 
gas  in  a state  of  purity,  unless  the  proportion  of  hydrogen  exceeded  50  per  cent,  it 
may  be  inferred  that  the  transpiration  time  of  pure  hydrocyanic  acid  vapour  is  be- 
tween 0*4375,  the  time  of  hydrogen,  and  0*4579,  the  observed  time,  but  much  nearer 
to  the  latter  than  to  the  former.  For  the  transpiration  of  gaseous  mixtures  of  more 
nearly  equal  density,  it  is  known,  on  the  contrary,  that  the  transpiration  time  does 
not  deviate  far  from  the  mean  time  of  the  constituents  when  transpired  separately. 
Taking  the  transpiration  time  of  air  as  0*9,  and  that  of  hydrocyanic  acid  vapour  as 
0*46,  then  36*48  volumes  of  the  first  and  63*52  volumes  of  the  second  would  give  a 
mean  time  of  0*6205. 

The  time  observed  of  a mixture  in  these  proportions  was  0*6390. 

Hydrocyanic  acid  is  composed  of  equal  volumes  of  cyanogen  and  hydrogen  united 
without  condensation.  The  transpiration  time  of  the  compound  gas  is  intermediate 
between  the  times  of  its  constituents. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


373 


6,  Hydrosulphuric  Acid. 

This  gas  was  evolved  by  the  action  of  hydrochloric  acid  upon  the  sulphide  of  anti- 
mony; it  was  washed  with  water,  and  afterwards  dried  by  passing  over  chloride  of 
calcium. 

(1.)  Hydrosulphuric  acid  was  first  transpired  by  a short  length  of  capillary  M,  of 
8’7fi  inches,  into  the  six-pint  aspirator-jar,  through  the  usual  range  of  28'5  to  23"5 
inches  of  the  attached  barometer:  thermometer  62°,  barometer  29’674  to  29'652 
inches.  The  following  observations  were  made  in  the  order  in  which  they  are  related : 
— times  of  air,  999  and  1001  seconds;  of  hydrosulphuric  acid,  692,  692  seconds;  of 
hydrosulphuric  acid  gas  saturated  with  the  vapour  of  bisulphide  of  carbon,  682,  680 
seconds  ; and  lastly,  of  hydrosulphuric  acid  again,  685,  685  seconds. 

The  ratio  of  the  first  hydrosulphuric  acid  to  air  is  0‘691,  and  of  the  second  0’685  ; 
the  ratio  of  the  hydrosulphuric  acid  saturated  with  the  vapour  of  bisulphide  of  carbon 
is  0'681,  or  differs  little  from  that  of  hydrosulphuric  acid  itself;  showing  that  these 
two  sulphur  compounds  nearly  coincide  in  transpirability.  Multiplying  these  results 


by  0‘9,  we  have — 

Transpiration  time  of  hydrosulphuric  acid  (1)  ....  0*6219 

Transpiration  time  of  hydrosulphuric  acid  (2)  ....  0*6165 

Mean  transpiration  time 0*6192 


This  gas  proved  less  uniform  in  its  rate  in  different  experiments  than  I have  gene- 
rally observed  for  other  gases,  at  least  with  the  present  capillary. 

In  a repetition  of  the  preceding  experiments,  thermometer  60°,  barometer  29*860  to 
29*858,  the  times  observed  were  for  air,  982, 983  and  981  seconds  ; for  hydrosulphuric 
acid  saturated  with  bisulphide  of  carbon,  659,  659,  659  seconds ; and  for  hydrosul- 
phuric acid  alone,  663,  664  seconds  ; which  give  the  ratios  to  air  of  0*671 1 and  0*6746. 
And  multiplying  by  0*9,  we  have — 

Transpiration  time  of  hydrosulphuric  acid 0*6071 

(2.)  Hydrosulphuric  acid  gas  was  also  transpired  by  means  of  the  long  capillary  M, 
52*5  inches  in  length,  into  the  two-pint  aspirator-jar.  It  was  then  supplied  from  a 
wash-bottle  with  a relief  tube  as  in  the  experiments  upon  cyanogen  and  ammonia, 
without  being  retained  over  water.  Thermometer  59°*5  Fahr.,  barometer  29*550  to 
29*292. 

The  times  of  air  were  1 134,  1134  seconds ; of  hydrosulphuric  acid,  782, 780  seconds  ; 
of  hydrosulphuric  acid  carried  through  a column  of  bisulphide  of  carbon  2^  inches  in 
depth  and  kept  at  the  fixed  temperature  of  59°*5,  773,  771,  772  seconds.  These  give 
the  ratios  to  air,  of  0*6887  for  hydrosulphuric  acid,  and  0*6808  for  hydrosulphuric 
acid  saturated  with  the  vapour  of  bisulphide  of  carbon  at  59°*5.  Also,  multiplying 
by  0*9,— 

Transpiration  time  of  hydrosulphuric  acid 0*6198 

MDCCCXLIX.  3 c 


374 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


This  last  result  almost  coincides  with  the  first  determinations  with  the  short 
capillary  M,  namely  0'6192.  The  mean  of  the  two  results  is, — 

Transpiration  time  of  hydrosulphuric  acid 0’6195 

The  mercury  in  the  gauge  tube  of  the  air-pump  was  soiled  by  these  experiments, 
and  the  tube  required  to  be  cleaned  after  them. 

7.  Bisulphide  of  Carbon. 

At  the  temperature  of  63°,  the  tension  of  the  vapour  of  bisulphide  of  carbon  was 
observed  to  be  10‘462  inches.  Experiments  were  made  with  air,  oxygen,  hydrogen 
and  carbonic  acid  gases,  all  saturated  with  the  vapour  of  bisulphide  of  carbon  at  63° 
and  with  barometer  from  29’874  to  29*850  inches.  The  short  capillary  K,  8*75  inches 
in  length,  was  made  use  of,  and  the  gas  was  transpired  into  the  six-pint  aspirator  jar. 
The  gases  were  impregnated  by  the  vapour  in  passing  through  a large  U-shaped  tube 
filled  with  cotton-wick  which  was  moistened  by  the  liquid  bisulphide  of  carbon. 

Air  alone  was  transpired  in  982  and  98.1  seconds ; air  saturated  with  bisulphide  of 
carbon  vapour  in  837  and  838  seconds ; oxygen  saturated  with  bisulphide  of  carbon 
vapour  in  895  and  896  seconds  ; hydrogen  saturated  with  bisulphide  of  carbon  vapour 
in  662  and  661  seconds;  carbonic  acid  saturated  with  bisulphide  of  carbon  vapour 
in  763  and  762  seconds.  The  ratios  appear  in  the  following  Table : — 

Transpiration  times  of  different  gases  saturated  with  CS2  at  63°. 


Air  =1. 

Oxygen  =1. 

Oxvffen  

0-9124 

0-8533 

0-7769 

0-6739 

0-8212 

0-7679 

0-6992 

0-6065 

Air 

Carbonic  acid 

Hydrogen  

It  may  be  safely  concluded  that  the  transpiration  time  of  bisulphide  of  carbon  is 
not  less  than  0*6065,  but  probably  sensibly  greater.  It  must,  according  to  former 
observations,  approach  very  closely  to,  if  it  does  not  actually  coincide  with,  0*6195, 
the  transpiration  time  of  hydrosulphuric  acid  gas. 

8.  Sulphurous  Acid. 

This  gas  was  evolved  by  the  action  of  copper  upon  sulphuric  acid,  was  washed 
with  water,  and  conveyed  in  a continuous  manner  to  a bottle  with  a relief  tube  from 
which  the  capillary  was  supplied,  as  in  the  experiments  with  ammonia  and  cyanogen. 
The  gas  was  dried  by  passing  over  pumice  soaked  in  oil  of  vitriol  before  reaching  the 
capillary. 

(1.)  With  short  capillary  K,  8*75  inches  in  length,  the  six-pint  aspirator-jar,  and 
usual  range  from  2*85  to  23*5  inches : thermometer  53°,  barometer  29*964  to  29*942 
inches. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


375 


The  time  of  air  was  970,  970  seconds;  of  sulphurous  acid,  714  and  711  seconds; 
ratio  of  latter  to  air,  07345.  Multiplying  by  0-9,  we  obtain — 

Transpiration  time  of  sulphurous  acid 0’6610 

(2.)  With  the  long  capillary  M,  52‘5  inches  in  length,  this  gas  was  transpired  into 
the  two-pint  jar:  thermometer  60°‘5,  barometer  29'880  to  29*878  inches. 

The  time  of  air  was  1120,  1120  and  1120  seconds;  the  time  of  sulphurous  acid 
814,  811  and  812  seconds.  Using  the  two  last  observations  only  for  sulphurous  acid, 
we  obtain  the  transpiration  time  0*7245  for  that  gas,  air  being  1 ; or  multiplying 
by  0-9,— 

Transpiration  time  of  sulphurous  acid 0’6520 

In  a second  series  of  experiments  with  the  same  capillary,  thermometer  58°  and 
barometer  from  29'880  to  29*886,  the  following  observations  were  made.  Time  of 
air,  1105,  1111,  1105  and  1111  seconds;  time  of  sulphurous  acid,  798,  797  and  798 


seconds,  and  ratio  to  air  0*7199.  This  gives — 

Transpiration  time  of  sulphurous  acid 0*6479 

The  mean  of  the  two  results  by  this  capillary  gives — 

Transpiration  time  of  sulphurous  acid 0*6500 

9.  Sulphuric  Acid. 


Both  air  and  oxygen  gas  saturated  with  the  vapour  of  anhydrous  sulphuric  acid 
were  transpired  under  the  pressure  of  the  atmosphere  into  an  air-pump  vacuum,  by 
the  short  capillary  K,  8*75  inches  in  length.  Certain  new  arrangements  of  the  appa- 
ratus, however,  were  required  in  operating  upon  so  highly  corrosive  a vapour  as  that 
of  sulphuric  acid.  Two  ounces  of  the  solid  sulphuric  acid  were  melted  by  heat  in  a 
U-tube  stuffed  with  asbestos,  and  having  while  liquid  impregnated  the  asbestos,  were 
allowed  to  cool  and  become  solid  again  before  the  air  or  other  gas  to  be  saturated 
with  sulphuric  acid  vapour  was  conducted  through  the  U-tube.  For  the  tin  conduct- 
ing tubes  of  the  former  arrangements,  glass  tubes  were  substituted,  and  the  air-pump 
was  employed  to  exhaust  a stout  globular  glass  globe  of  six  pints  in  capacity  and 
provided  with  three  openings,  which  was  employed  as  the  aspirator  cavity.  Two  of 
the  openings  of  the  globular  receiver  were  in  the  sides  and  one  at  the  bottom  of  the 
receiver ; by  one  of  the  former  openings  the  globular  receiver  was  connected  with 
the  transpiring  capillary  and  by  the  other  with  the  air-pump ; a tube  containing 
carbonate  of  potash  being  interposed  between  the  receiver  and  the  air-pump,  to  arrest 
the  acid  vapours  and  prevent  them  from  reaching  the  air-pump,  when  the  latter  was 
used  for  exhausting  the  globular  receiver.  The  third  and  lower  opening*  communi- 
cated with  a gauge  barometer,  by  which  the  tension  of  the  gas  or  vapour  within  the 
globular  receiver  was  observed.  The  mercury  in  this  barometer  was  found  to  adhere 
slightly  to  the  glass  and  not  to  descend  with  an  entirely  level  surface  in  the  transpira- 
tion experiments,  owing  to  a slight  chemical  action  of  the  acid  vapour  upon  the 

3 c 2 


376 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


mercury.  This  circumstance  prevents  the  times  being  observed  with  the  same  pre- 
cision as  in  other  gases. 

With  the  thermometer  from  72°  to  74°,  and  barometer  from  30-076  to  30*028 
inches,  the  times  of  descent  of  the  gauge  barometer  from  28*5  to  23*5  inches  were, 
with  air,  865  and  863  seconds ; with  air  saturated  with  sulphuric  acid  vapour  at 
73°  Fahr.,  960,  961,  and  958  seconds.  The  ratio  of  the  last  times  to  air  is  T1106; 
and  multiplying  by  0*9,  we  obtain, — 

Transpiration  time  of  air  saturated  with  vapour  of  SO3  at  73°  . . 0*9993 

The  tension  of  the  vapour  of  anhydrous  sulphuric  acid  at  73°  was  observed  to  be 
1 1*50  inches. 

The  experiments  on  sulphuric  acid  vapour  were  repeated:  thermometer  67°'5, 
barometer  29*914  to  29*908  inches  ; the  range  of  the  gauge  barometer  now  observed, 
however,  being  only  from  28*5  to  24*5  inches. 

The  time  for  air  was  695  and  694  seconds  ; for  oxygen  saturated  with  the  vapour 
of  sulphuric  acid  at  67°*5,  786  and  782  seconds ; for  oxygen  alone  at  68°,  774 
seconds  ; and  for  air  alone  again  692  seconds.  The  result  to  be  deduced  is, — 
Transpiration  time  of  oxygen  saturated  with  vapour  of  SO3  at  67°'5  . . 1*0130 

The  sensible  equality  of  the  times  of  air  observed  at  the  beginning  and  end  of  the 
experiments  proves  that  the  working  of  the  apparatus  was  not  deranged  by  the  sul- 
phuric acid  vapour.  It  is  evident  that  the  time  of  pure  sulphuric  acid  vapour  itself 
cannot  deviate  far  from  that  of  oxygen  gas.  Sulphuric  acid  appears  to  be  one  of  the 
very  few  gases,  the  transpirability  of  which,  if  not  really  coincident  with,  is  slightly 
inferior  to,  or  slower  than,  that  of  oxygen. 

10.  Chlorine. 

The  transpiration  time  of  chlorine  has  a peculiar  interest  as  that  of  an  elementary 
substance.  The  same  arrangements  were  had  recourse  to  with  this  corrosive  gas  as 
with  sulphuric  acid.  It  was  found  necessary,  in  addition,  to  preserve  a small  column 
of  water  above  the  mercury  in  the  gauge  barometer,  to  defend  the  metal  from  the 
action  of  the  chlorine,  or  at  least  to  prevent  the  surface  of  the  metal  from  becoming 
foul  and  adhesive.  This  gas  immediately  reached  the  capillary,  like  ammonia,  from 
a bottle  with  a relief  tube,  to  permit  the  escape  of  the  redundant  supply.  It  was 
dried  by  means  of  chloride  of  calcium. 

(1.)  The  transpiration  was  made  by  capillary  K,  8*75  inches  in  length,  into  the  six- 
pint  globular  receiver  as  aspirator,  from  28*5  to  23*5  inches  by  the  gauge  barometer 
attached  to  the  latter:  thermometer  70°  to  71°,  barometer  30*222  to  30*208  inches. 

The  times  of  air  in  two  experiments  were  865  and  866  seconds  ; the  times  of  chlo- 
rine 670  and  672  seconds  ; giving  the  ratio  to  air  of  0*7753.  Multiplying  the  latter 
number  by  0*9,  we  have — 

Transpiration  time  of  chlorine 0*6978 

(2.)  In  a second  series  of  experiments  with  the  same  capillary,  the  following 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


377 


observations  were  made ; the  thermometer  being  72°  to  74°,  and  barometer  30’248  to 
30'218  inches. 

The  times  of  air  were  858,  860  and  859  seconds  ; the  times  of  carbonic  acid  711 
and  712  seconds  ; the  times  of  chlorine  670,  670,  670  and  670  seconds ; the  time  of 
air  again  866  and  867  seconds.  A slight  increase  in  the  air-time  is  observed,  after 
the  chlorine  experiments,  but  I would  refer  this  increase  more  to  the  rise  of  two  de- 
grees in  temperature  between  the  first  and  last  observations,  than  to  any  derange- 
ment in  the  apparatus.  Taking  the  last  observed  air  as  the  standard  of  comparison 
for  the  chlorine,  and  the  first  observed  air  for  the  carbonic  acid,  we  find — 


Air=l. 

Oxygen =1. 

Transpiration  time  of  chlorine  

Transpiration  time  of  carbonic  acid... 

0*7732 

0*8282 

0*6959 

0*7454 

But  the  true  transpiration  time  of  chlorine  gas  is  probably  less  than  0*6959,  for  the 
true  time  of  carbonic  acid  is  certainly  less  than  0*7 454,  the  time  obtained  above  for  the 
latter  gas.  The  present  capillary,  it  has  been  already  remarked,  is  one  of  too  small 
resistance  to  bring  out  the  true  transpiration  time  of  a gas  whose  effusion  rate  differs 
very  widely  from  its  transpiration  rate.  The  present  experiment  indeed  is  not  incon- 
sistent with  the  true  transpiration  time  of  chlorine,  being  2 or  3 per  cent,  lower  than 
that  observed,  or  falling  as  low  as  0*66,  that  is,  two-thirds  of  the  time  of  oxygen. 

(3.)  The  transpiration  of  chlorine  was  also  observed  by  means  of  the  long  capillary 
M,  52'5  inches  in  length,  with  the  same  six-pint  glass  globular  receiver  as  aspirator- 
jar.  The  fall  observed  by  the  gauge  barometer  was  only  3 inches,  or  from  28*5  to 
25*5  inches.  Thermometer  58°,  barometer  29*742  inches. 

The  time  of  air  was  1907  and  1911  seconds;  of  chlorine  1432  and  1395  seconds. 
The  difference  of  37  seconds  in  the  two  observed  times  of  chlorine,  which  is  so  con- 
siderable, arose  from  the  action  of  chlorine  upon  the  mercury ; for  notwithstanding 
that  the  latter  was  covered  with  water,  its  surface  became  so  uneven  that  the  obser- 
vations could  not  be  made  with  any  great  nicety.  The  first  observation  of  chlorine 
gives  the  time  of  that  gas  0*7501  referred  to  air,  and  0*6751  referred  to  oxygen ; the 
second  observation  gives  the  time  of  chlorine  0*7307  referred  to  air,  and  0*6576  re- 
ferred to  oxygen.  Calculating  from  1413*5  seconds,  the  mean  of  the  two  observed 
times  for  chlorine,  we  obtain — 


Air  = l. 

Oxygen =1. 

Transpiration  time  of  chlorine  

0*7404 

0*6664 

The  transpiration  time  of  chlorine  appears  therefore  to  be  about  two-thirds  of  the 
time  of  oxygen  ; or,  chlorine  passes  through  a tube  with  1^  time  the  velocity  of 
oxygen. 


378 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


11.  Bromine  and  Hydrochloric  Acid. 

The  only  observations  which  I possess  upon  the  transpiration  of  these  two  sub- 
stances were  made  by  means  of  the  short  capillary  K,  of  8'75  inches  in  length,  the 
six-pint  globular  receiver  being  the  aspirator,  and  the  fall  being  as  usual  from  28’5 
to  23*5  inches  of  the  gauge  barometer.  For  both  the  bromine  and  hydrochloric  acid 
the  bottle  and  relief  tube  were  employed  also  as  before,  to  regulate  the  supply  of  gas 
to  the  capillary.  Chloride  of  calcium  was  employed  to  dry  the  gases. 

The  time  of  air  was  846,  848  seconds;  of  hydrochloric  acid,  693,  693  seconds;  of 
air  saturated  with  the  vapour  of  bromine  at  76°,  889,  889  and  889  seconds  ; of  hydro- 
gen saturated  with  the  vapour  of  bromine,  760,  760  seconds : thermometer  from  73° 
to  76°,  barometer  30  230  to  30' 178  inches.  In  an  observation  which  was  made  at 
the  same  time  upon  the  tension  of  bromine  vapour,  it  was  found  that  liquid  bromine 
placed  in  an  air-pump  vacuum  depressed  the  mercurial  gauge  9T9  inches  at  76°, 
which  may  therefore  be  taken  as  the  tension  of  the  vapour  of  bromine  in  the  present 
experiments.  The  results  are  as  follows  : — 


Air=l. 

Oxygen=l. 

Transpiration  time  of  hydrochloric  acid  gas  

Transpiration  time  of  9*2  vol.  bromine  and  21’0  vol.  air 

Transpiration  time  of  9*2  vol.  bromine  and  21*0  vol.  hydrogen 

0-8181 

1-0496 

0-8973 

0-7363 

0-9446 

0-8076 

It  appears  that  the  transpiration  time  of  hydrochloric  acid  observed,  0‘7363,  is 
greater  than  that  of  chlorine,  0'66,  while  that  of  hydrocyanic  acid  was  found  less, 
on  the  contrary,  than  that  of  cyanogen. 

Bromine  vapour  increases  the  transpiration  time  of  air,  and  is  therefore  less  trans- 
pirable.  This  vapour,  however,  does  not  appear  to  be  greatly  more  transpirable  than 
sulphuric  acid  vapour  or  oxygen  gas. 

12.  Ether  {Oxide  of  Ethyl,  Hj  O). 

The  ether  employed  was  carefully  washed  with  water,  to  deprive  it  of  alcohol,  and 
afterwards  dried  by  agitation  with  pounded  chloride  of  calcium.  Dry  hydrogen  and 
other  gases  were  impregnated  with  the  vapour  of  this  substance  in  the  same  manner 
as  with  bromine. 

(1.)  The  first  experiments  were  made  with  the  short  capillary  K,  8‘76  inches  in 
length ; the  gas  being  transpired  as  usual  under  the  pressure  of  the  atmosphere  into 
the  exhausted  six-pint  aspirator  jar,  through  the  range  from  28’5  to  23‘5  inches  of 
the  gauge  barometer  of  the  air-pump  : thermometer  56°,  barometer  29‘670  to 
29708  inches.  The  tension  of  the  ether  vapour  at  56°  being  found  12*85  inches, 
the  mixture  transpired  may  be  represented  as  composed  of  12*85  volumes  ether  vapour 
and  16*85  volumes  gas;  or  of  43*26  ether  vapour  and  56*74  gas  in  100  volumes. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


379 


The  time  of  air  was  988,  988  seconds  ; of  hydrogen  474,  473  seconds ; of  hydrogen 
gas  saturated  with  ether  vapour  at  56°,  498,  500  seconds  ; of  oxygen  gas  saturated 
with  ether  vapour  at  the  same  temperature,  696  and  695  seconds.  The  transpiration 
times  deducible  from  these  observations  are, — 


Air=l. 

Oxygen  = 1, 

Transpiration  time  of  hydrogen  

Transpiration  time  of  ether  vapour  and  hydrogen  

Transpiration  time  of  ether  vapour  and  oxygen  

0-4792 

0-5051 

0-7040 

0-4.312 

0-4546 

0-6336 

It  thus  appears  that  the  transpiration  time  of  hydrogen,  0-4312,  is  only  increased  to 
0*4546  by  43-26  per  cent,  of  ether  vapour.  As  the  influence  of  hydrogen  upon  the  rate 
of  transpiration  of  the  dense  gases  and  vapours  is  scarcely  sensible,  this  may  be  held 
as  proving  that  the  time  of  ether  vapour  does  not  sensibly  exceed  the  time  of  the 
hydrogen  mixture,  0*4546.  But  as  the  experiment  has  been  made  with  a capillary  of 
small  resistance,  it  is  not  impossible  that  the  normal  time  of  ether  vapour  may  be 
still  sensibly  less. 

(2.)  The  capillary  M,  52*5  inches  in  length,  with  the  two-pint  aspirator,  was  now 
used,  the  other  arrangements  remaining  as  before  : thermometer  68°*5  to  69°,  baro- 
meter 30*242  to  30*264  inches. 

The  time  of  air  was  1084,  1084  seconds  ; of  air  saturated  with  ether  at  68°*5  (59*5 
ether  vapour  to  40*5  air),  675,  676  and  673  seconds  ; of  hydrogen  saturated  with  ether 
vapour  at  68°*5  (59*5  ether  vapour  to  40  5 hydrogen),  533,  529  and  531  seconds  ; of 
oxygen  saturated  with  ether  vapour  at  68°*5  (59*5  ether  vapour  to  40*5  oxygen),  728, 
725  and  727  seconds ; of  hydrogen  alone,  529,  529  seconds.  The  tension  of  ether 
vapour  was  observed  at  the  time  to  be  17’95  inches  at  69°.  The  results  deduced  from 
these  experiments  are  as  follows : — 


Air=  1. 

Oxygen  = 1. 

Transpiration  time  of  ether  vapour  and  air 

0-6224 

0-4898 

0-6771 

0-4880 

0-5601 

0-4408 

0-6039 

0-4392 

Transpiration  time  of  59*5  ether  vapour  and  40-5  hydrogen  ... 

Transpiration  time  of  59*5  ether  vapour  and  40-5  oxygen 

Transpiration  time  of  hydrogen  

In  this  capillary  of  great  resistance,  the  time  of  hydrogen  is  therefore  not  sensibly 
affected  by  nearly  one  and  a halftimes  its  volume  of  ether  vapour,  from  which  it  may 
be  inferred  that  the  transpiration  time  of  ether  vapour  itself  does  not  diverge  sensibly 
from  that  of  hydrogen.  The  near  if  not  perfect  coincidence  in  transpirability  in  these 
two  substances  is  very  remarkable,  considering  their  great  dissimilarity  in  physical 
characters,  particularly  in  weight,  the  densities  of  hydrogen  and  ether  vapour  being 
as  1 to  37. 

Although  hydrogen  and  ether  may  have  the  same  transpirability,  still  the  influence 
which  each  of  these  gases  exerts  upon  the  transpiration  of  other  gases  with  which  it 


380 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


is  mixed,  is  widely  different.  It  will  be  seen  by  the  experiments  above  on  ether  and 
air,  or  ether  and  oxygen,  that  the  transpiration  time  inclines  most  to  the  ether  rate, 
while  in  hydrogen  mixtures  the  time  also  deviates  from  the  mean  of  the  mixed  gases, 
but  greatly  in  the  direction  of  the  rate  of  the  other  gas,  and  not  towards  the  hydro- 
gen rate.  The  density  of  a gas  is  no  doubt  an  important  element  in  this  influence. 

In  an  experiment  with  the  short  capillary  K,  the  time  of  olefiant  gas  was  reduced 
from  0*5246  to  0*4816,  by  saturation  with  ether  vapour  at  60°*5. 

The  rates  of  hydrogen  and  ether  appear  to  diverge  from  each  other  in  experiments 
made  at  a high  temperature.  The  water  in  the  copper  trough  in  which  the  long 
capillary  M was  always  placed,  with  the  view  of  commanding  a constant  temperature, 
was  heated  to  203°  (95°  centig.),  and  preserved  at  that  temperature  during  the  con- 
tinuance of  the  following  experiments.  Thermometer  in  air  60°*5,  barometer  29*956 
to  29*982  inches. 

Time  of  air  1634  and  1637  seconds  ; of  hydrogen,  798  and  797  seconds  ; of  hydro- 
gen saturated  with  ether  vapour  at  60°*5,  863,  863  seconds.  As  the  gas  transpired 
was  measured  at  60°*5  instead  of  203°,  the  temperature  at  which  it  passed  through 
the  capillary,  these  times  fall  to  be  diminished  in  the  proportion  of  the  volume  of  air 
at  203°  and  at  60°*5  respectively.  We  thus  obtain  as  the  three  mean  times  in  which 
equal  volumes  were  transpired  at  203°, — air  1282*4  seconds,  hydrogen  625*9  seconds, 
and  hydrogen  saturated  with  ether  vapour  at  60°*5,  677*3  seconds. 


Air=l. 

Oxygen  = 1 . 

TransDiration  time  at  203°  Fa  hr.  of  hvdrosen  

0-4880 

0-3281 

0-4392 

0-4753 

Transpiration  time  at  203  of  hydrogen  saturated  at  60°‘5  with  ether  vapour 

While  air  and  hydrogen  preserve,  at  203°,  their  usual  ratio  of  transpirability,  ether 
vapour  appears  therefore  to  become  sensibly  less  transpirable  at  the  high  temperature. 


13.  Methylic  Ether  {Oxide  of  Methyl,  C2H3O). 

This  vapour  was  evolved  in  a continuous  manner  in  proportion  as  required  for 
transpiration,  with  the  arrangements  necessary  for  gases  soluble  in  water.  The 
vapour  was  passed  over  both  hydrate  of  potash  and  chloride  of  calcium.  The  expe- 
riments were  made  with  the  short  capillary  K,  8*75  inches  in  length,  like  the  first 
experiments  with  common  ether.  Thermometer  56°,  barometer  29*650. 

Time  of  air  993  and  991  seconds ; of  methylic  ether,  532  and  532  seconds;  of  methylic 
ether  saturated  with  the  vapour  of  common  ether  at  56°,  508,  506  and  507  seconds. 


Transpiration  times. 


Air=l. 

Oxygen  =1. 

IVTethylie  ether  

0-5363 

0-3111 

0-4826 

0-4600 

Methylic  ether  saturated  with  ether  vapour  at  56° 

PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


381 


The  time  of  methylic  ether,  0‘4826,  is  decidedly  longer  than  that  of  common  ether, 
0*4546,  as  the  latter  was  formerly  observed  by  the  same  capillary ; and  consequently 
an  addition  of  ether  vapour  shortens  the  methylic  ether  time,  as  appears  in  the 
second  experiment,  where  the  transpiration  time  of  such  a mixture  falls  to  0*4600. 

14.  Hydrochloric  Ether  {Chloride  of  Ethyl,  C4  Hg  Cl). 

The  experiments  were  made  with  the  same  short  capillary  K,  8*75  inches  in  length, 
and  with  the  other  arrangements  as  for  the  two  preceding  ethers.  Thermometer  56°, 
barometer  from  29*794  to  29*758  inches. 

The  time  of  air  was  980  and  981  seconds  ; of  hydrochloric  ether,  548,  544  and  543 
seconds. 


Air=l. 

Oxygen  = 1. 

Transpiration  time  of  hydrochloric  ether 

0-5543 

0-4988 

It  would  be  unsafe  to  draw  any  conclusion  from  a single  experiment  upon  this 
ether  and  that  experiment  made  with  a capillary  of  inferior  resistance,  but  it  may  be 
remarked  that  the  time  of  this  ether  approaches  to  half  the  time  of  oxygen,  while  the 
density  of  the  vapour  is  little  more  than  double  that  of  this  gas  ; the  theoretical  den- 
sity of  hydrochloric  ether  vapour  being  32*25  to  hydrogen  1 and  oxygen  16. 

15.  Hydrochloric  Methylic  Ether  {Chloride  of  Methyl,  C2  H3  Cl). 

This  ether,  which  like  the  two  last  is  entirely  vaporous  at  the  temperature  of  the 
experiments,  was  prepared  by  distilling  together  half  a pound  of  wood-spirit,  one  and 
a half  pounds  of  oil  of  vitriol  and  one  pound  of  common  salt.  The  gas  was  exposed 
to  a large  quantity  of  dilute  caustic  soda  in  two  wash-bottles,  and  dried  afterwards 
by  chloride  of  calcium.  The  same  capillary  and  arrangements  were  employed  as  in 
the  immediately  preceding  experiments.  Thermometer  54°,  barometer  29*862  to 
29*856  inches. 

The  time  of  air  was  973,  973  seconds ; of  chloride  of  methyl,  592,  587  and  582 
seconds;  of  chloride  of  methyl  again,  after  changing  the  solution  of  caustic  soda  in 
the  wash-bottles,  592  and  592  seconds.  Calculating  from  the  last  observed  time  of 
chloride  of  methyl,  we  have — 


Air  = l. 

Oxygen  = 1. 

Transpiration  time  of  chloride  of  methyl 

0-6084 

0-5475 

It  thus  appears  that  the  chloride  of  methyl  has  a longer  time,  or  is  more  slowly 
transpired  than  the  corresponding  chloride  of  ethyl ; as  the  oxide  of  methyl  was  also 
found  to  be  less  transpirable  than  the  oxide  of  ethyl.  Indeed  the  difference  between 
the  two  oxides  and  between  the  two  chlorides  appears  to  be  the  same,  or  about  0*045 
MDCccxLix.  3 D 


38'2 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


in  both  cases.  This  is  in  accordance  with  the  general  observation,  that  transpiration 
is  promoted  by  increase  of  density.  The  theoretical  density  of  chloride  of  methyl  is 
25'25  to  hydrogen  1 and  oxygen  16. 

16.  Water. 

Although  great  care  was  always  taken  to  dry  air  when  transpired,  as  well  as  other 
gases,  in  all  experiments,  still  it  does  not  appear  that  the  rate  of  air  is  much  affected  by 
the  presence  of  aqueous  vapour  unless  the  latter  is  present  in  considerable  proportion. 

The  times  observed  by  capillary  K,  8’75  inches  in  length,  into  a vacuum,  were  for 
air  dried  by  chloride  of  calcium  1008  seconds,  and  for  air  drawn  afterwards  directly 
from  the  atmosphere,  of  which  the  temperature  was  60°  and  the  dew-point  32°,  1006 
and  1006  seconds.  So  small  a difference  may  be  due  to  accidental  causes. 

With  dry  air  at  60°,  the  times  with  the  same  capillary  were,  upon  another  occasion, 
1021  and  1021  seconds;  and  with  air  of  60°  temperature,  but  containing  aqueous 
vapour  with  the  dew-point  at  38°,  1018  and  1017  seconds. 

In  other  experiments,  the  presence  of  aqueous  vapour  appeared  to  occasion  a 
sensible  retardation  in  the  time  of  air.  The  transpiration  was  made  into  a vacuum  by 
the  capillary  M,  52'5  inches  in  length ; the  temperature  of  the  capillary  being  main- 
tained at  58°‘5,  and  the  barometer  varying  from  29’798  to  29‘832  inches.  The  air 
was  charged  with  vapour  by  passing  through  a tube  filled  with  cotton  wick,  which 
had  been  previously  moistened  with  dilute  sulphuric  acid  of  different  strengths.  The 
time  of  dry  air  was  1115,  1115  seconds;  of  air  carried  over  the  fourth  hydrate  of 
sulphuric  acid  (HO  .S03-f3H0),  1117,  1117  seconds  ; of  air  passed  over  the  eighth 
hydrate  (HO  . SO3-I-7HO),  1120  and  1121  seconds  ; of  air  passed  over  the  eighteenth 
hydrate  (HO  . 803-!- 17HO),  1122,  1122  and  1121  seconds.  Here  we  observe  in  the 
dampest  air  a slight  but  sensible  increase  of  the  air  time,  not  exceeding  7 seconds. 
But  on  repeating  the  experiment  immediately  afterwards  with  dry  air,  the  time  was 
1120  and  1119  seconds,  or  within  two  seconds  of  the  immediately  preceding  obser- 
vations with  moist  air.  Indeed  the  transpiration  of  moist  air  appears  to  produce  a 
slight  but  sensible  retardation  of  a persistent  character,  probably  from  the  condensa- 
tion of  a film  of  moisture  on  the  inner  surface  of  the  capillary,  which  is  not  imme- 
diately removed  by  the  subsequent  passage  of  dry  air. 

With  the  same  capillary,  thermometer  57°  and  barometer  30T36  to  30'078  inches, 
dry  air  was  transpired  in  1089,  1089  seconds  ; dry  hydrogen  in  532  and  532  seconds  ; 
air  saturated  with  aqueous  vapour  at  57°‘5  in  1098,  1098  seconds ; hydrogen  satu- 
rated with  aqueous  vapour  at  the  same  temperature,  in  548  and  548  seconds ; and 
lastly,  dry  air,  first  in  1106  seconds,  and  afterwards  in  1084  and  1085  seconds.  Here 
the  damp  air  is  less  transpirable,  volume  for  volume,  than  dry  air  by  9 seconds.  Also, 
dry  air  immediately  following  the  damp  air  does  not  recover  its  usual  transpirability 
in  the  first  experiment. 

These  experiments  upon  damp  and  dry  air  seem  to  indicate  that  the  transpiration 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


383 


time  of  aqueous  vapour  does  not  differ  greatly  from  that  of  air  itself.  The  influence 
of  aqueous  vapour  upon  the  time  of  hydrogen,  however,  is  considerably  less  than  that 
of  air  upon  the  same  gas,  and  therefore  suggests  a more  rapid  transpiration. 

17*  Alcohol. 

Air  was  impregnated  with  the  vapour  of  alcohol  of  specific  gravity  0'835  at  60°, 
barometer  29'358.  The  tension  of  the  vapour  of  alcohol  of  specific  gravity  0‘813  at 
60°  is  estimated  at  T23  inch.  The  capillary  K,  8'76  inches  in  length,  was  made  use 
of,  with  an  air-pump  vacuum,  as  in  all  these  experiments. 

The  time  of  dry  air  was  1013  and  1014  seconds  ; of  air  containing  alcohol  vapour, 
1011  and  1012  seconds.  The  rate  of  air  is  scarcely  affected,  and  consequently  the 
time  of  alcohol  vapour  must  approximate  to  that  of  air. 

1 8.  Naphtha  and  Coal-gas. 

In  experiments  made  with  air  saturated  with  the  vapour  of  coal-tar  naphtha  at  62°, 
the  capillary  K being  employed,  the  times  obtained  for  air  alone  were  978  and  979 
seconds ; for  air  saturated  with  naphtha  vapour,  949  and  949  seconds.  The  trans- 
piration time  of  air  is  diminished  30  seconds,  showing  that  the  volatile  hydrocar- 
bons of  naphtha  are  highly  transpirable,  like  ether  vapour.  The  time  of  coal-gas, 
taken  from  the  service-pipes  of  a London  company,  and  observed  in  the  same  cir- 
cumstances, was  621  and  622  seconds;  of  the  same  coal-gas  impregnated  with 
naphtha  vapour,  621  and  621  seconds,  or  the  naphtha  vapour  produced  no  sensible 
change  in  the  transpirability  of  the  gas ; showing  a near  coincidence  in  their  trans- 
pirabilities.  The  transpiration  time  of  the  coal-gas,  reduced  to  the  oxygen  scale,  is 
0’5716,  or  a little  more  than  protocarburetted  hydrogen,  0‘5510. 

That  a considerable  quantity  of  naphtha  vapour  was  taken  up  by  the  coal-gas, 
notwithstanding  that  its  transpiration  was  unaffected,  appears  in  certain  experiments 
which  were  made  with  a particular  object  upon  the  effusion  of  the  same  gases.  The 
capillary  was  removed  and  replaced  by  a plate  of  platinum  foil,  G of  former  paper, 
having  an  extremely  minute  aperture,  the  other  arrangements  remaining  the  same. 
The  gases  were  all  moistened  with  water.  For  the  passage  of  equal  volumes  into  an 
air-pump  vacuum  (the  six-pint  aspirator-jar,  through  the  usual  range  from  28’5  to  23'5 
inches  of  the  attached  barometer),  the  times  were,  at  61°,  for  air,  434  and  434  seconds  ; 
for  hydrogen,  139  and  139  seconds;  for  coal-gas,  314  and  314  seconds;  for  coal-gas 
saturated  with  naphtha  vapour  at  61°, 331  and  331  seconds;  for  hydrogen  and  naphtha 
vapour,  194  and  193  seconds ; and  for  air  with  naphtha  vapour,  503  and  503  seconds. 
It  is  to  be  remembered  that  the  densities  of  the  gases  effused  are  in  the  proportion  of 
the  squares  of  these  times,  and  may  be  deduced  from  the  latter.  The  time  of  coal- 
gas  is  increased  by  the  addition  of  naphtha  vapour,  but  to  a much  less  extent,  than 
hydrogen  and  air  are,  no  doubt  from  the  former  being  from  the  first  partially  saturated 
with  naphtha  vapour. 


3 D 2 


384 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


A good  deal  of  light  could  be  obtained,  I believe,  upon  the  composition  and  value 
of  coal-gas  by  a combination  of  effusion  and  transpiration  experiments.  Great 
density,  which  would  be  indicated  by  slow  effusion,  is  always  valuable,  unless  when 
occasioned  by  air,  carbonic  oxide  or  carbonic  acid,  which  gases  exclusively  make  the 
transpiration  slow ; so  that  slow  effusion  with  rapid  transpiration  would  mark  the 
coal-gas  of  superior  quality. 

III.  TRANSPIRATION  OF  AIR  OF  DIFFERENT  DENSITIES  OR  ELASTICITIES. 

A series  of  observations  on  air  varying  in  density  from  0‘5  to  2 atmospheres,  made 
with  the  long  20-feet  capillary  E in  my  former  paper,  appeared  to  establish  the  con- 
clusion that  “ for  equal  volumes  of  air  of  different  densities,  the  times  of  transpiration 
are  inversely  as  the  densities.”  The  law  of  Effusion,  or  flow  of  air  into  a vacuum  by 
an  aperture  in  a plate,  is  entirely  different ; equal  volumes  of  air  of  all  densities 
passing  in  equal  times. 

With  the  short  capillary  K,  8*75  inches  in  length,  the  result  was  now  found  to  be 
materially  different.  Air  in  three  different  states  of  rarefaction  was  drawn  into  a sus- 
tained vacuum  from  a globular  receiver  of  which  the  capacity  was  56’5  cubic  inches, 
standing  over  water.  To  command  the  desired  density  of  the  air  in  the  globular 
receiver,  the  little  system  of  the  latter  and  the  basin  of  water  in  which  it  stood  was 
retained  within  a large  air-pump  receiver,  the  atmosphere  of  which  was  adjusted  to 
the  requisite  pressure.  Thermometer  62°,  external  barometer  from  29'984  to  29*936 
inches. 

Transpiration  of  equal  volumes  of  Air. 


Density  or  elasticity. 

Time  in  seconds. 

Experiment  I. 

Experiment  II. 

1 atmosphere 

2172 

2173 

0'75  atmosphere 

2948 

2946 

0*5  atmosphere 

5292 

5288 

It  will  be  observed  that  the  time  5292  seconds  for  air  of  0*5  density  is  considerably 
more  than  double  2172  seconds,  the  time  for  air  of  1 density. 

With  compressed  air,  varying  in  density  from  1 to  2*5  atmospheres,  the  deviation 
from  the  law  was  equally  conspicuous ; the  times  of  transpiration  of  equal  volumes 
at  1,  1*25,  1*5,  1*75,  2 and  2*5  atmospheres,  being  in  the  ratio  of  1,  0*8625,  0*7553, 
0*6834  and  0*5519,  instead  of  1,  0*8,  0*6666,  0*5714,  0*5  and  0*4. 

On  operating,  however,  with  the  long  capillary  M,  52*5  inches  in  length,  and  of 
great  resistance,  results  were  again  obtained  in  strict  accordance  with  the  law.  The 
air  was  drawn  from  a metallic  digester  provided  with  a gauge  barometer,  in  which 
it  was  preserved  of  a constant  elasticity ; this  digester  itself  being  supplied  from  a 
second  similar  digester,  in  which  the  air  was  in  a state  of  still  higher  compression. 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


385 


The  air  was  transpired  into  the  two-pint  aspirator-jar  (capacity  about  72  cubic  inches) 
upon  the  plate  of  the  air-pump,  for  the  usual  range  of  the  gauge  barometer  from  28’5 
to  23‘5  inches.  Thermometer  66°,  external  barometer  30' 122  to  30*086  inches. 


Transpiration  of  equal  volumes  of  Air. 


Density  or  elasticity. 

Time  in  seconds. 

Reduced  time 
of  means. 

Calculated  or 
theoretical  times. 

Experiment  I. 

Experiment  II. 

] atmosphere 

1095 

1096 

1095-5 

1095-5 

1*25  atmosphere 

707 

707 

883-1 

884-8 

1'5  atmosphere 

493 

493 

739-3 

737-3 

1‘75  atmosphere 

359 

359 

628-25 

632 

2 atmospheres  

277 

276 

553 

553 

2*25  atmospheres  

218 

217 

489-4 

491-5 

2*5  atmospheres  

176 

176 

440 

442 

The  column  of  “Time  in  seconds  ” contains  the  times  of  the  fall  of  the  air-pump 
barometer  from  28*5  to  23*5  inches  actually  observed,  and  which  are  produced  by  the 
admission  to  the  aspirator-jar  of  an  equal  volume  of  air  of  constant  density.  These 
times  must  therefore  be  multiplied  by  the  density  in  atmospheres  of  the  air  transpired, 
to  obtain  the  reduced  times  of  the  following  column.  It  will  be  observed  that  these 
reduced  times  are  in  perfect  harmony  with  the  “Calculated  times”  of  the  last 
column.  Indeed  nothing  could  illustrate  more  strongly  the  great  precision  of  which 
transpiration  experiments  are  susceptible,  than  these  results. 

The  conclusion  to  be  drawn  from  the  present  observations  with  the  capillary  M, 
and  the  old  observations  with  E,  as  compared  with  the  observations  made  with  the 
short  capillary  K,  is  that  to  bring  out  the  normal  effect  of  densities  on  transpiration, 
a greater  resistance  and  length  of  tube  are  necessary  than  are  required  for  the  ob- 
servations of  the  normal  relations  in  the  transpiration  times  of  such  gases  as  oxygen, 
nitrogen  and  hydrogen ; for  the  short  capillary  K,  which  fails  so  much  in  the  law 
of  densities,  exhibits  the  other  relations  nearly  with  as  much  accuracy  as  the  long 
capillary  M.  The  marked  superiority  also  of  the  20-feet  tube  E over  the  8-inch  tube 
K,  although  the  power  of  resistance  of  these  two  capillaries  is  nearly  equal,  suggests 
again  the  idea  that  resistance  produced  by  elongation  of  the  capillary  acts  differently 
from  an  equal  resistance  produced  by  contracting  the  diameter  of  the  capillary,  and 
more  advantageously  in  transpiration  experiments. 


IV.  TRANSPIRATION  OF  AIR  AND  OTHER  GASES  AT  DIFFERENT  TEMPERATURES. 

The  experiments  which  I have  made  upon  the  transpiration  of  air  and  also  of  other 
gases  at  different  temperatures  are  very  numerous,  but  not  altogether  satisfactory. 
Looking  upon  the  experiments  as  only  preliminary,  I shall  confine  myself  at  present 
to  a statement  of  results  without  detail,  and  endeavour  to  return  to  the  subject  at 
some  future  opportunity. 


386 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


The  transpiration  of  equal  volumes  becomes  slower  as  the  temperature  rises.  The 
experiments  which  follow  upon  air,  carbonic  acid  and  hydrogen,  were  made  upon 
different  days  with  slightly  different  barometric  pressures,  so  that  the  absolute  times 
of  one  gas  cannot  be  compared  with  another ; but  this  is  unnecessary  for  our  present 
purpose.  The  capillary  employed  was  M,  52'5  inches  in  length,  and  of  great  resist- 
ance. 


Table  XIV. — Transpiration  of  equal  volumes  at  different  temperatures. 


Temperature. 

Time  in  seconds. 

Air. 

Carbonic  acid. 

Hydrogen. 

32  Fahr. 

1054*1 

857*9 

545*4 

59 

1092*8 

897*4 

557*8 

86 

1133*4 

931*5 

577*7 

113 

1175*7 

969*4 

598*8 

140 

1211  ' 

993*9 

615*9 

The  difference  of  time  of  transpiration  at  the  two  extreme  temperatures,  32°  and 
140°,  is  157*9  seconds  for  air,  136  seconds  for  carbonic  acid,  and  70*5  seconds  for 
hydrogen.  The  differences,  calculated  in  the  proportion  of  the  transpiration  times  of 
the  same  gases  at  the  temperatures  usually  observed  (56°  to  74°),  namely  air  0*9, 
carbonic  acid  0‘73,  and  hydrogen  0'44,  are  for  carbonic  acid  128*1  seconds  instead  of 
136,  and  for  hydrogen  73*2  seconds  instead  of  70'5.  It  would  be  unsafe  to  conclude 
from  these  small  deviations  that  the  transpiration  of  the  three  gases  in  question  is 
unequally  affected  by  heat  in  the  range  of  temperature  from  32°  to  140°;  for  at 
temperatures  distant  from  the  temperature  of  the  atmosphere,  the  unavoidable  errors 
of  observation  increase  in  magnitude.  The  increment  upon  the  time  of  air  was 
156'2  seconds,  and  upon  hydrogen  62*8  seconds,  at  140°,  in  a repetition  of  the  same 
experiments. 

My  most  unexceptionable  experiments  all  concur  in  showing  that  no  sensible 
change  takes  place  in  the  transpiration  ratios  of  hydrogen,  nitrogen  and  carbonic 
oxide,  at  temperatures  so  high  as  347°  Fahr.  Thus  the  observed  transpiration  times 
of  a mixture  of  equal  volumes  of  hydrogen  and  carbonic  oxide  at  60°  and  347°,  were 
0’8870  and  0*8853  ; the  transpiration  times  of  air  observed  at  the  same  temperatures 
being  taken  as  unity.  The  transpiration  times  of  a mixture  of  equal  volumes  of 
hydrogen  and  nitrogen,  referred  to  the  times  of  air  in  the  same  manner,  were  at  65°, 
0-8939  ; at  347°,  0*8924  ; again,  at64°*5,  0*8930  ; and  at  347°,  0*8872.  The  transpira- 
tion ratios  are  thus  as  nearly  as  possible  constant  at  these  widely  distant  tempera- 
tures. 

The  transpiration  times  of  air  and  hydrogen  alone,  at  203°,  were  found  on  two  dif- 
ferent occasions  as  1 to  0*4841,  and  1 to  0*4880.  Multiplying  these  hydrogen  times 
by  0*9  to  bring  them  to  the  scale  of  oxygen,  we  have  for  the  transpiration  times  of 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


387 


hydrogen  at  203°,  0-4357  and  0-4392,  numbers  which  might  have  been  obtained  at 
atmospheric  temperatures. 

Carbonic  acid,  however,  appears  to  present  a sensible  deviation  from  this  uni- 
formity of  rate.  In  a series  of  observations  made  upon  this  gas  at  60°,  203°,  299° 
and  347°,  its  transpiration  time  referred  to  air  at  the  same  temperatures  was  0-8291, 
0-8551,  0-8/77  and  0-8907  ; and  referred  to  oxygen,  0-7448,  0-7541,  0-7741  and  0-7855. 
The  transpiration  time  of  carbonic  acid  at  347°  varied  in  other  experiments  from 
|)-7729  to  0-7905,  the  time  of  oxygen  being  1.  The  protoxide  of  nitrogen  gave  the 
pumber  0-7969  at  the  same  high  temperature. 

The  time  of  oxygen  appears  also  to  become  relatively  slower  at  high  tempei-atures, 
Although  much  less  considerably  than  carbonic  acid.  It  gave  the  numbers  0-8877 
and  0-8860  for  air  at  347°,  instead  of  0-8984,  the  number  at  low  temperatures.  As 
we  may  assume  from  its  uniform  relation  to  hydrogen  that  the  nitrogen  remains 
constant,  it  follows  that  the  oxygen  has  become  relatively  slower  in  transpiration  at 
the  high  temperature. 

If  oxygen  deviates  from  a supposed  normal  rate  at  high  temperatures,  it  cannot 
necessarily  coincide  with  that  rate  at  any  lower  temperature,  which  is  accidental, 
such  as  that  of  the  atmosphere.  But  this  influence  of  heat  upon  the  transpiration 
time  of  oxygen  is,  I believe,  still  sensible  at  the  low  temperature  in  question. 

By  increasing  the  time  of  oxygen,  this  influence  of  heat  may  be  the  cause  of  that 
slight  deviation,  so  uniform  in  its  amount,  of  the  observed  times  of  air  and  nitrogen 
from  their  theoretical  times,  which  was  always  remarked.  I am  disposed  then  to 
look  upon  the  slight  inconstancy  of  transpiration  rate  observed  in  some  gases  at  dif- 
ferent temperatures,  as  a fact  of  the  same  class  as  the  deviations  from  their  theoretical 
specific  gravities  observed  in  a greater  or  less  degree  in  the  same  substances,  and  to 
those  other  points  in  which  all  the  gaseous  bodies  we  have  to  operate  upon  depart  in 
some  measure  from  the  mechanical  idea  of  a perfect  gas. 

The  normal  effect  of  temperature  upon  transpiration,  as  observed  in  air,  varies  I 
find  with  the  resistance  of  the  capillary  in  a much  higher  degree  than  any  other  pro- 
perty of  transpiration ; the  retardation  from  the  same  change  of  temperature  being 
much  greater  in  a capillary  of  great  than  small  resistance.  The  resistance  of  a capil- 
lary such  as  M,  which  exhibits  so  exactly  the  law  of  densities,  is  insufficient  to  bring 
out  the  full  effeet  of  temperature.  With  the  fine  tubes  of  the  compound  capil- 
lary, on  the  other  hand,  the  limit  to  the  retarding  influence  of  heat  seems  to  be 
reached.  The  retardation  then  appears  to  be  simply  in  proportion  to  the  expansion; 
and  rarefaction  by  heat,  therefore,  to  have  the  same  effect  upon  transpiration  as  ex 
pansion  from  diminished  pressure. 

In  illustration  of  this  inequality  of  action  upon  heated  air,  I may  refer  to  results 
obtained  by  two  capillary  tubes  of  small  and  of  intermediate  resistance,  before  stating 
the  normal  results  of  capillaries  of  extreme  resistance. 

With  the  copper  capillary  tube  described  in  my  former  paper,  and  which  admitted 


388 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


1 cubic  inch  of  air  into  a vacuum  in  22  seconds,  the  time  of  passage  of  a constant 
volume  of  air  into  a vacuum  was  853  seconds  at  60°,  899  seconds  at  1 16°,  and  924'5 
seconds  at  152°.  The  theoretical  times,  or  those  corresponding  to  the  rarefaction  by 
heat  at  these  temperatures,  are  853,945  and  1004  seconds.  Here  the  observed  times 
at  1 16°  and  152°,  are  46  and  79’5  seconds  shorter  respectively  than  the  times  obtained 
by  calculation  ; and  the  difference  in  transpirability  observed  at  the  high  and  low 
temperatures  only  amounts  to  about  one-half  of  what  it  should  be. 

With  capillary  M,  of  which  the  resistance  is  seven  times  greater  than  the  last 
capillary,  the  observed  times  of  air  at  59°  (15°  centig.),  and  at  203°  (95°  centig.),  were 
1106‘5  and  1286‘4  seconds.  The  time  at  the  higher  temperature  is  1400  seconds 
by  calculation,  and  the  observed  time  is  therefore  113*6  seconds  deficient.  The  dif- 
ference at  the  high  and  low  temperatures  amounts  to  nearly  two-thirds  of  the  differ- 
ence which  theory  requires.  The  deviation  is  therefore  less  than  with  the  preceding 
capillary. 

Air  compressed  in  the  globular  digester  with  pressure  gauge,  of  which  the  capacity 
was  reduced  to  about  10  cubic  inches  by  the  introduction  of  mercury,  was  transpired 
by  a small  capillary  V,  3 inches  in  length,  into  the  atmosphere,  from  a pressure  be- 
ginning at  17  inches  above  that  of  the  barometer.  Thermometer  50°,  barometer 
29*546  to  29*590. 

The  resistance  of  this  capillary  is  excessive.  Under  a pressure  of  17  inches  of 
mercury,  1 cubic  inch  of  air  is  transpired  in  2329  seconds,  or  the  volume  transpired 
is  0*0258  cubic  inch  per  minute. 

Table  XV. — Transpiration  of  air  under  pressure  (into  air)  at  different  temperatures. 


Pressure  by  gauge  barometer. 

Time  in  seconds. 

Ratio  at  203°, 
Time  at  50°  = i. 

Thermometer  50°  Fahr. 

Thermometer  203°  Fahr. 

17  inches. 

0 

« 

0 

16 

1370 

2329 

1-7000 

15 

1445 

2442 

1-6900 

14 

1541 

2601 

1-6880 

From  17  to  14  inches 

4356 

7372 

1-6924  1 

Now  the  volume  of  air  at  3*2°  being  =1,  at  50°  it  is  1*0366,  and  at  203°,  1*3480. 
But  it  must  be  remembered  that  the  volume  actually  transpired  in  the  experiment 
was  greater  at  203°  than  that  at  50®,  in  proportion  as  the  volume  of  air  is  expanded  at 
the  higher  of  these  two  temperatures,  that  is  as  1*3480  to  1*0366  (volume  at  32°=  1). 
It  is  therefore  necessary  to  reduce  the  observed  times  of  the  table  at  203°  in  that  pro- 
portion. The  time  from  17  inches  to  16  is  thus  reduced  from  2329  to  1792*5  seconds, 
which  last  is  the  true  time  of  the  passage  of  the  same  volume  at  203°  as  passed  at 
50°.  The  law  requires  that  the  times  of  equal  volumes  should  be  inversely  as  the 
densities  of  air  at  these  temperatures,  or  as  1*0366  to  1*3480.  Thus  calculated  from 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


1370  seconds,  the  time  at  50°,  the  time  at  203°  is  1780-9  seconds  ; the  time  actually 
observed  was  1792-5  or  11-6  seconds  more,  a close  approximation  considering  the 
difficulties  of  the  experiment. 

But  the  resistance  does  not  require  to  be  so  excessive  as  in  capillary  V to  bring 
out  the  law  of  temperature.  It  appeared  equally  distinct  in  a capillary  tube,  having 
only  one-ninth  of  the  resistance  of  V for  equal  lengths.  This  tube  however  was 
used  in  lengths  of  4^  inches  (instead  of  3 inches),  so  that  its  resistance  is  properly 
stated  at  one-sixth  of  V.  A sheaf  was  put  together  of  thirty  lengths  of  the  new  tube, 
forming  the  compound  capillary  Q.  The  digester  was  employed  of  its  full  capa- 
city, of  72  cubic  inches,  to  contain  the  compressed  air,  which  was  allowed  to  escape 
by  the  channels  of  Q into  the  atmosphere.  The  range  of  pressure  was  from  20  inches 
to  8.  The  observed  times  at  49°  and  203°  without  reduction  were  802,  799  and  798 
seconds  at  the  low  temperature,  and  1350  and  1347  seconds  at  the  high  temperature. 
Taking  the  means  800  and  1349  seconds  and  reducing  as  in  the  experiments  with  V, 
we  have  1036-1  seconds  for  the  high  temperature.  Now  the  calculated  time  for  that 
temperature  is  104T6  seconds,  or  only  5*5  seconds  above  the  observed  time.  The 
barometer  during  these  experiments  marked  from  30-044  to  30-058  inches. 

In  another  series  of  experiments,  the  time  observed  at  49°  being  797  seconds,  the 
times  observed  after  reduction,  at  certain  intermediate  temperatures,  were  as 
follows : — 

Table  XVI. — Times  of  transpiration  of  Air  (into  air)  in  seconds. 


Temperature. 

Observed  time. 

Calculated  time. 

Error  of  observation. 

49  Fahr. 

797 

797 

96 

879-3 

870-4 

+ 8-9 

141 

950-1 

935-8 

+ 14-3 

203 

1020-8 

1032-1 

-11-3 

The  deviations  of  the  observed  from  the  calculated  times,  from  8-9  to  14-3  seconds, 
are  small  considering  the  difficulty  of  maintaining  the  temperature  constant  in  the 
experiments.  Nor  are  they  always  in  the  same  direction.  This  appears  in  a third 
series  of  experiments,  conducted  in  the  same  manner  as  the  last,  of  which  I subjoin 
the  results. 

Table  XVII. — Times  of  transpiration  of  Air  (into  air)  in  seconds. 


Temperature. 

Observed  time. 

Calculated  time. 

Error  of  observation. 

49  Fahr. 

797 

797 

96 

897-3 

870-4 

+ 8-9 

141 

932-3 

940-8 

-8-5 

These  observations  leave  little  doubt  that  the  transpiration  of  air  at  different  tem- 
peratures takes  place  according  to  the  law  by  which  the  times  above  have  been  cal- 

3 £ 


MDCCCXLIX. 


390 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


culated.  In  one  experiment  which  was  made  upon  oxygen  at  49°  and  203°,  the  in- 
crease upon  the  time  at  the  higher  temperature  corresponded  within  0‘7  per  cent,  of 
the  increase  upon  the  time  of  air,  and  evidently  followed  the  same  ratio.  I may  add 
that  the  transpiration  times  of  air  and  oxygen,  as  determined  by  a single  observation 
in  each  case,  were  0"9058  to  1 for  the  compound  capillary  Q,  and  0'9020  to  1 for  the 
single  capillary  V of  extreme  resistance. 

In  conclusion  I may  sum  up  the  general  results  hitherto  obtained  in  this 
inquiry. 

1.  The  velocities  with  which  different  gases  pass  through  capillary  tubes  bear  a 
constant  relation  to  each  other,  and  appear  to  constitute  a peculiar  and  fundamental 
property  of  the  gaseous  form  of  matter,  which  I have  termed  transpirability.  The 
constancy  of  these  relations,  or  of  the  transpiration  times,  has  been  observed  for 
several  of  the  gases  for  tube  resistances  varying  in  amount  from  1 to  1000.  These 
relations,  there  is  reason  to  believe,  are  more  simple  in  their  expression  than  the 
densities  of  the  gases.  The  following  relations  are  particularly  remarkable. 

The  velocity  of  hydrogen  is  exactly  double  that  of  nitrogen  and  carbonic  oxide. 

The  velocities  of  nitrogen  and  oxygen  are  inversely  as  the  specific  gravities  of  these 
gases. 

The  velocity  of  binoxide  of  nitrogen  is  the  same  as  that  of  nitrogen  and  carbonic 
oxide. 

The  velocities  of  carbonic  acid  and  protoxide  of  nitrogen  are  equal,  and  directly 
proportional  to  their  specific  gravities,  when  compared  with  oxygen. 

The  velocity  of  protocarburetted  hydrogen  is  0-8,  that  of  hydrogen  being  1. 

The  velocity  of  chlorine  appears  to  be  that  of  oxygen ; of  bromine  vapour  and 
sulphuric  acid  vapour  the  same  as  that  of  oxygen. 

Ether  vapour  appears  to  have  the  same  velocity  as  hydrogen  gas. 

Olefiant  gas,  ammonia  and  cyanogen  to  have  equal  or  nearly  equal  velocities,  which 
approach  closely  to  double  the  velocity  of  oxygen. 

Hydrosulphuric  acid  gas  and  bisulphide  of  carbon  vapour  appear  to  have  equal 
or  nearly  equal  velocities. 

The  compounds  of  methyl  appear  to  have  a less  velocity  than  the  corresponding 
compounds  of  ethyl,  but  to  be  connected  by  a certain  constant  relation. 

2.  The  resistance  of  a capillary  tube  of  uniform  bore  to  the  passage  of  any  gas  is 
directly  proportional  to  the  length  of  the  tube. 

3.  The  velocity  of  passage  of  equal  volumes  of  air  of  the  same  temperature  but  of 
different  densities  or  elasticities,  is  directly  proportional  to  the  density. 

4.  Rarefaction  by  heat  has  a similar  and  precisely  equal  effect  in  diminishing 
the  velocity  of  the  transpiration  of  equal  volumes  of  air,  as  the  loss  of  density  and 
elasticity  by  diminished  pressure  has. 

5.  A greater  resistance  in  the  capillary  is  required  to  bring  out  the  third  result,  or 
the  law  of  densities,  than  appears  necessary  for  the  first  and  second  results  ; and  a 


PROFESSOR  GRAHAM  ON  THE  MOTION  OF  GASES. 


391 


resistance  still  further  increased,  and  the  highest  of  all,  to  bring  out  the  fourth  result 
or  the  law  of  temperatures. 

6.  Finally,  it  will  be  remarked  throughout,  that  transpiration  is  promoted  by  den- 
sity, and  equally  whether  the  increased  density  is  due  to  compression,  to  cold,  or  to 
the  addition  of  an  element  in  combination,  as  the  velocity  of  oxygen  is  increased,  by 
combining  it  with  carbon  without  change  of  volume,  in  carbonic  acid  gas. 

It  was  no  part  of  my  plan  to  investigate  the  passage  of  gases  through  tubes  of 
great  diameter,  and  to  solve  pneumatic  problems  of  actual  occurrence,  such  as  those 
offered  in  the  distribution  of  coal-gas  by  pipes.  But  I may  state  that  the  results  must 
be  similar,  with  truly  elastic  gases  such  as  air  and  carburetted  hydrogen,  whether  the 
tubes  are  capillary  or  many  inches  in  diameter,  provided  the  length  of  the  tube  is  not 
less  than  4000  times  its  diameter,  as  in  the  long  glass  capillaries  of  my  early  experi- 
ments. The  small  propulsive  pressure  applied  to  coal-gas  is  also  favourable  to  trans- 
piration, as  well  as  the  great  length  of  the  mains  ; and  I should  therefore  expect  the 
distribution  of  coal-gas  in  cities  to  exemplify  approximately  the  laws  of  gaseous 
transpiration.  The  velocity  of  coal-gas  should  be  1‘575,  that  of  air  being  1,  under 
the  same  pressure  (p.  383).  And  with  a constant  propulsive  pressure  in  the  gaso- 
meter, the  flow  of  gas  should  increase  in  volume  with  a rise  of  the  barometer  or  with 
a fall  in  temperature,  directly  in  proportion  to  the  increase  of  its  density  from  either 
of  these  causes. 


3 £ 2 


ih 

■ '&■ 


\ , i 


liupPI^  ■. i - 3< ’ 4^^-  '■*'  " ' '^'v 

■/:-':p.-h^ 


E><‘'t!>  r<  ■ ;v'  ■ ■ : t ':  ■ I'  -i  *j#l 


. ‘ '; ti;  -ii;  ^ tiitH  ' 

•'  A r'^  ‘ «*  » '■'  *'■■  ■ ■ ■*-'!**» 

or-vrffE  -•;,.  -•  r.-^  n 

"V  ■ •'  ■ ,iS;',  . ^ 


P: 

"■  '‘:  .'mi 


' ' 


_.t2  V ■ 


V.;';,.’  ’if.  ^ ;■"■  ■ ''l' > ■ .'i' ■ Vt -■  ^ ^oiT; . ;iU 


I 'i.  > '.'ft;:T'sl'  'Ji-t?'  Vt'i’ ' ■■  ■■'■  ;'r;,:i{i'i'<.v  ■* 


-*>8#^;  ifir  lii  pil}.^yv\  ‘H'r  'n  'l.‘  ‘.  ^ 

vUiv/  ';'‘r  ‘>/i''r  !j  ^ ' 'Ui*? 


•‘I 


; . ' .■  . ..  ..  • :U  :.  ■., 


:■)'■ 


■ SI  ' ! 


' ' . i 


. ■ “ . ■ .V  V,  ■' JSsIiS' f'l' •• 

;. /, . ' if,  ; = , ' <-■ 
' . ' ' ' ' ,'  ,^  v.i'ty",?'- /'  -J.'"*  ^ 

■ ' •'•  •■■■  ■'’■■»'-  • ' .. V ‘ i’’  '■''  ■■,■.,■•, 


' <P- 


\p!.  ,.»i^ 


'.• 4 • 


^ ; ■’• 

u >'fRi>-iji  V'-v  -I . 


’ P0¥n 


■^U.T 


» 

■’  --.oi' 


'p' 


‘rl 


XX.  Examination  of  the  yroximate  Principles  of  some  of  the  Lichens. — Part  II. 

By  John  Stenhouse,  F.R.S. 


Received  February  14, — Read  March  29,  1849. 

Gyrophora  pustulata*. 

This  lichen  has  been  long  employed  in  the  manufacture  of  archil,  though  the  quan- 
tity of  colouring  matter  contained  in  it  is  by  no  means  considerable,  being  little  more 
than  a twelfth  of  that  in  the  Roccella  Montagnei. 

The  Gyrophora  pustulata  is  the  Tripe  de  Roche  of  the  Canadian  hunters,  who,  not- 
withstanding its  disagreeably  bitter  taste,  occasionally  use  it  as  an  article  of  food  in 
seasons  of  scarcity.  A memorable  instance  of  this  occurred  in  the  case  of  Messrs. 
Frankltn  and  Richardson,  who  during  their  disastrous  journey  to  the  shores  of  the 
Polar  sea,  after  the  failure  of  their  supplies,  subsisted  almost  entirely  upon  this  lichen 
during  several  weeks.  The  Gyrophora  pustulata,  on  which  I operated,  was  brought 
from  Norway,  where  it  is  annually  collected  in  considerable  quantity  for  the  manu- 
facture of  archil.  The  colouring  principle  was  extracted  by  maceration  with  milk  of 
lime,  and  was  precipitated  in  a gelatinous  state  by  neutralizing  the  lime  solution  by 
muriatic  acid,  precisely  in  the  way  so  frequently  described  in  the  first  part  of  this 
paper.  I may  mention  however  that  the  most  convenient  mode  of  effecting  this  ope- 
ration on  a considerable  scale,  is  to  steep  the  lichens,  previously  cut  into  small  pieces, 
for  some  hours  in  water  till  they  are  thoroughly  soaked.  They  should  then  be  strati- 
fied with  a great  excess  of  slacked  lime  in  a large  barrel  furnished  with  a false  bottom 
pierced  with  small  holes,  under  which  a spigot  is  placed;  in  fact,  in  exactly  such  an 
arrangement  as  is  employed  by  the  soap-makers  for  preparing  caustic  lyes.  Water  is 
then  poured  into  the  top  of  the  barrel,  and  when  it  has  remained  on  the  mixture  of 
the  lime  and  the  lichens  for  an  hour  or  so,  it  is  drawn  off  by  opening  the  spigot,  when 
the  solution  runs  off  quite  clear  of  a deep  brownish  colour.  Water  is  still  added  in 
successive  quantities  so  long  as  the  lime  solution,  when  neutralized  by  muriatic  acid, 
continues  to  afford  a precipitate.  The  great  advantage  of  this  arrangement  is,  that 
it  can  be  easily  and  rapidly  executed  on  a large  scale,  and  that  the  extraction  and 
filtration  are  effected  by  a single  operation. 

The  gelatinous  precipitate  from  the  lichen,  which  had  a reddish  brown  colour  after 
being  washed  with  cold  water  by  decantation  to  remove  adhering  muriatic  acid,  was 
collected  on  a cloth  filter  and  dried  by  a very  gentle  heat.  When  the  greater  portion 

* I am  indebted  to  the  kindness  of  John  King,  Esq.,  of  George  M'Intosh  and  Cot,  chemical  manufacturers, 
Glasgow,  for  the  lichens  employed  in  this  part  of  the  investigation. 


394 


MR.  STENHOUSE  ON  THE  EXAMINATION  OF  THE 


of  the  moisture  it  contained  had  been  removed,  it  was  found  advisable  to  treat  it  for 
a short  time  with  a small  quantity  of  dilute  spirits  of  wine  at  nearly  a boiling  tempe- 
rature. This  had  the  effect  of  freeing  it  from  a greenish-coloured  resinous  substance. 
The  undissolved  portion  of  the  precipitate,  whicli  had  now  become  much  whiter,  was 
next  digested  with  strong  alcohol  and  a considerable  quantity  of  purified  animal 
charcoal,  great  care  however  being  taken  to  prevent  the  liquid  from  boiling.  The 
solution  was  then  filtered,  and  on  standing  for  some  hours  the  colouring  principle 
was  deposited  in  small  prisms  arranged  in  stars.  By  repeated  digestions  with  alcohol 
and  animal  charcoal  it  was  rendered  colourless,  when  it  had  a silky  lustre.  A con- 
siderable portion  of  the  original  precipitate  however  did  not  dissolve  in  the  alcohol, 
and  consisted  of  a brownish  coloured  humus-like  substance. 

The  colouring  principle  of  the  Gyrophora  pustulata,  which  I shall  call  gyrophoric 
acid,  when  pure  forms  small  white  soft  crystals,  which  have  neither  taste  nor  smell. 
It  is  almost  insoluble  both  in  cold  and  in  boiling  water.  It  is  also  but  sparingly 
soluble  both  in  ether  and  in  alcohol.  It  is  much  less  soluble  therefore  in  hot  alcohol 
than  either  orsellic,  lecanoric  or  erythric  acids.  Its  solutions  have  no  action  upon  test- 
paper.  Gyrophoric  acid  has  no  saturating  power,  for  the  smallest  quantity  of  either 
potash  or  ammonia  gives  its  solutions  an  alkaline  reaction.  When  gyrophoric  acid 
is  boiled  for  a short  time  with  a considerable  excess  of  any  of  the  alkalies  or  alkaline 
earths,  it  gives  off  carbonic  acid  and  is  converted  into  orcine.  When,  on  the  other  hand, 
it  is  boiled  with  a very  small  portion  of  alkali  only,  it  is  decomposed  in  the  same  way 
as  the  orsellic,  erythric  and  other  similar  acids,  and  yields  a corresponding  interme- 
diate acid,  which  is  more  soluble  in  water  and  exhibits  more  distinctly  acid  properties 
than  the  gyrophoric  acid  from  which  it  has  been  derived.  Gyrophoric  acid  strikes  the 
same  bright  red  fugitive  colour  with  hypochlorite  of  lime  which  appears  to  be  charac- 
teristic of  this  class  of  colouring  matters.  The  red  solution  which  it  yields  is  how- 
ever rather  more  durable  than  those  of  the  above-mentioned  acids.  Gyrophoric  acid 
is  very  slightly  soluble  even  in  a large  excess  of  a cold  aqueous  solution  of  ammonia, 
and  it  is  precipitated  by  ammonia  from  its  alcoholic  solution,  without  however  com- 
bining with  any  of  that  alkali.  When  gyrophoric  acid  is  heated  with  an  alcoholic 
solution  of  ammonia  it  readily  dissolves,  but  at  the  same  time  it  is  decomposed  with 
the  formation  of  an  intermediate  acid.  When  gyrophoric  acid  is  macerated  with  an 
excess  of  ammonia  and  exposed  for  a considerable  time  to  the  air,  it  is  slowly  con- 
verted into  a purplish-red  colouring  matter  similar  to  that  which  the  analogous  acids 
furnish  in  the  same  circumstances. 

A quantity  of  gyrophoric  acid,  prepared  in  the  way  already  described  and  repeat- 
edly washed  with  boiling  water  to  free  it  from  any  trace  of  the  ether  compound  which 
might  have  adhered  to  it,  was  subjected  to  an  analysis  : — 

I.  0*2785  grm.  substance  dried  in  vacuo,  and  burned  with  chromate  of  lead,  gave 
0*621  carbonic  acid  and  0*123  water. 

II.  0*175  ditto  gave  0*3925  Co^  and  0*082  water. 


PROXIMATE  PRINCIPLES  OF  SOME  OF  THE  LICHENS. 


395 


0*1798  substance  gave  0*403  carbonic  acid  and  0*081  water. 

Calculated  numbers.  Found. 

per  cent.  I.  II. 

III. 

36 C 2700 

61*02 

60*81 

61*16 

61*12 

18  H 225 

5*09 

4*90 

5*20 

5*00 

15  0 1500 

33*89 

34*29 

33*64 

33*88 

4425 

100*00 

10000 

100*00 

100*00 

These  numbers  therefore  give  C^g  H^g  as  the  formula  of  gyrophoric  acid. 

Ether  compound. 

When  gyrophoric  acid  is  boiled  for  some  hours  in  strong  spirits  of  wine  it  is  readily 
converted  into  an  ether,  a considerable  quantity  of  a resinous  matter  and  orcine  being 
also  formed  during  the  operation.  The  ether  is  very  soluble  in  hot  water,  and  is  puri- 
fied from  adhering  resinous  matter  exactly  in  the  same  way  as  the  ethers  of  the  orsellic, 
lecanoric  and  analogous  acids,  which  in  its  external  properties  it  very  closely  re- 
sembles. 

I.  0‘2532  grm.  ether  dried  in  vacuo,  gave  with  chromate  of  lead  0‘570  Co^  and 
0*144  Ho. 

II.  0*2/8  substance  gave  0*625  carbonic  acid  and  0*155  water. 

Calculated  numbers.  Found  numbers. 


C 40 

3000 

61*39 

I. 

61*33 

II. 

61*31 

H23 

287 

5*87 

6*31 

6*19 

0 16 

1600 

32*74 

32*36 

32*50 

4887 

100*00 

100*00 

100*00 

These  numbers  give  C35  Hjg  O^g-f  C4  Hg  O4  as  the  rational  formula  of  the  gyro- 
phoric ether. 

Gyrophoric  acid  also  readily  forms  a corresponding  methyl  compound  when  it  is 
boiled  for  some  hours  with  wood-spirit.  In  all  its  characters  it  perfectly  agrees  with 
the  analogous  compounds  of  lecanoric  and  orsellic  acids. 

Gyrophoric  acid  dissolves  very  readily  in  a slight  excess  of  baryta,  and  when  the 
solution  is  supersaturated  by  an  acid  the  gyrophoric  acid  precipitates  unchanged.  A 
quantity  of  gyrophoric  acid  was  dissolved  in  a cold  solution  of  baryta  and  the  excess 
of  the  base  removed  by  a stream  of  carbonic  acid.  The  precipitate,  which  consisted 
of  a mixture  of  carbonate  of  baryta  and  the  organic  salt,  was  collected  on  a filter  and 
dried  by  a gentle  heat.  The  dried  precipitate  was  then  repeatedly  digested  in  strong 
spirits  of  wine,  in  which  the  organic  salt  dissolved,  though  with  difficulty,  the  car- 
bonate of  baryta  remaining  on  the  filter.  On  standing  for  some  time,  the  clear  solu- 
tion deposited  the  baryta  compound  in  silky  crystals.  This  salt  is  insoluble  in  cold 
alcohol.  The  hot  spirits  appear  to  have  partially  altered  it,  for  on  subjecting  it  to 
analysis,  though  it  appeared  to  have  an  uniform  composition,  yet  on  decomposing  it 


396 


MR.  STENHOUSE  ON  THE  EXAMINATION  OF  THE 


by  an  acid  and  recrystallizing,  the  organic  acid  it  contained  was  found  to  have  a 
different  composition  from  that  of  gyrophoric  acid  ; from  which  it  also  differed  in  its 
properties,  being  much  more  soluble  in  water  and  also  more  distinctly  acid. 

An  alcoholic  solution  of  gyrophoric  acid  gives  no  precipitate  with  an  alcoholic 
solution  of  sugar  of  lead,  but  it  yields  a pretty  bulky  precipitate  with  both  an  aqueous 
and  an  alcoholic  solution  of  subacetate  of  lead.  Though  I made  many  trials  I was 
unable  to  obtain  these  precipitates  of  anything  approaching  to  an  uniform  composi- 
tion. Neither  was  I more  successful  in  forming  any  other  definite  compounds  of 
gyrophoric  acid  by  which  its  atomic  weight  might  have  been  more  definitely  ascer- 
tained. 

Lecanora  tart  area. 

This  lichen,  like  the  Gyrophora  pustulata,  has  been  employed  from  a very  early 
period  in  the  manufacture  of  archil.  The  Lecanora  tartarea  is  found  in  considerable 
abundance  in  the  hilly  districts  of  the  northern  parts  of  both  Scotland  and  Ireland, 
though  what  is  usually  met  with  in  commerce  is  chiefly  obtained  from  Norway  and 
its  neighbouring  countries.  The  lichen  on  which  I operated  was  from  Norway.  Its 
colouring  principle  was  extracted  by  milk  of  lime,  exactly  in  the  way  already  de- 
scribed. The  quantity  of  colouring  principle  it  contained  was,  comparatively  speak- 
ing, small,  not  exceeding  that  in  the  Gyrophora  pustulata.  The  precipitate  thrown 
down  from  the  lime  solution  by  muriatic  acid  had  a brownish-red  colour.  It  was 
washed  with  cold  water,  collected  on  a cloth  filter  and  cautiously  dried.  It  was  then 
digested  with  a little  dilute  spirits,  which  removed  a greenish  coloured  resinous 
substance  precisely  similar  to  that  contained  in  the  Gyrophora  pustulata.  The  portion 
of  the  precipitate  which  did  not  dissolve  in  the  weak  spirits  was  next  digested  in 
strong  alcohol  assisted  by  a considerable  quantity  of  animal  charcoal.  The  filtered 
solution  deposited  the  colouring  principle  in  small  silky  prisms  arranged  in  stars. 
These  crystals  at  first  had  a yellowish  tinge,  but  by  being  repeatedly  digested  with 
animal  charcoal,  they  were  rendered  quite  colourless.  A considerable  portion  of  the 
original  gelatinous  precipitate  did  not  dissolve  in  the  hot  alcohol,  and  appeared,  as  in 
the  case  of  the  preceding  lichen,  to  consist  of  a brownish  coloured  humus-like  sub- 
stance. The  purified  acid  from  the  Lecanora  tartarea  was  dried  in  vacuo  and  burned 
with  chromate  of  lead. 

I.  0T53  substance  gave  0-342  Co^  and  0-071  water. 

II.  0-250  substance  gave  0'561  Co^  and  0-115  water. 


Calculated  numbers. 

Found  numbers. 

per  cent. 

I. 

II. 

36  C 

2700 

60-02 

61-96 

61-20 

18  H 

225 

5-09 

5-15 

5-10 

15  O 

1500 

33-89 

33-89 

33-70 

4425 

100-00 

100-00 

100-00 

PROXIMATE  PRINCIPLES  OF  SOME  OF  THE  LICHENS. 


397 


These  numbers  give  C36  Hjg  Ojg  as  the  formula  of  the  acid  in  the  Lecanora  tartarea, 
which  is  exactly  the  formula  of.  gyrophoric  acid.  In  fact  the  acid  in  the  Lecanora 
tartarea  is  identical  in  all  its  properties  and  reactions  with  the  acid  in  Gyrophora 
pustulata,  so  that  no  doubt  can  be  entertained  that  both  lichens  contain  one  and  the 
same  colouring  principle,  viz.  gyrophoric  acid. 

The  Ether  Compound. 

Gyrophoric  ether  was  also  formed  by  boiling  the  acid  from  the  Lecanora  tartarea 
in  strong  spirits.  As  might  have  been  expected,  it  proved  also  identical  in  compo- 
sition and  properties  with  that  obtained  from  the  acid  of  the  Gyrophora  pustulata. 
The  following  are  the  results  of  its  analysis  : — 

I.  0-337  ga-m.  ether  dried  in  vacuo  and  burned  with  chromate  of  lead,  gave  0 7^95 
carbonic  acid  and  0'191  water. 

II.  0-296  grm.  gave  0-6658  carbonic  acid  and  0-165  water. 


Calculated  numbers. 

Found  numbers. 

per  cent. 

I. 

II. 

C 40 

3000 

61-39 

61-46 

61-30 

H23 

287 

5-87 

6-29 

6-19 

0 16 

1600 

32-74 

32-25 

32-51 

4887 

100-00 

100-00 

100-00 

The  rational  formula  for  the  gyrophoric  ether  from  the  acid  in  the  Lecanora  tartarea 
is  therefore  Cgg  H^g  035+04  Hg  O3. 

It  is  certainly  not  a little  singular  that  the  ether  compounds  of  this  whole  series  of 
acids,  the  lecanoric,  the  erythric,  the  alpha  and  beta  orsellic  acids,  and  here  again  the 
gyrophoric  acid,  should  approach  each  other  so  closely  in  their  general  properties 
and  in  their  per  cent,  composition.  Mr.  Schunck  has  been  induced  by  this  circum- 
stance to  think  it  probable  that  all  this  class  of  acids  are  coupled  acids  containing 
lecanoric  acid  and  an  adjunct,  and  that  the  ethers  which  they  yield  are  in  fact  only 
one  compound,  viz.  lecanoric  ether.  Mr.  Schunck’s  hypothesis  is,  however,  much 
weakened  from  the  fact  that  we  possess  no  means  of  reproducing  lecanoric  acid 
from  the  so-called  lecanoric  ether,  for  when  any  of  these  ethers  are  acted  on  by  an 
alkali,  the  organic  acid  they  contain  undergoes  decomposition  as  well  as  the  com- 
pound itself.  Besides,  it  appears  somewhat  gratuitous  to  infer  merely  from  the  per 
cent,  composition  of  these  ethers  that  they  all  contain  lecanoric  acid,  and  are  in 
fact  lecanoric  ether,  as  any  person  may  easily  convince  himself,  by  a few  trials,  that 
considerable  alterations  may  be  made  on  the  formulae  of  these  acids  without  mate- 
rially affecting  the  per  cent,  composition  of  their  ethers. 

Brom-orcine. 

In  the  former  paper  on  the  proximate  Principles  of  some  of  the  Lichens,  read 
before  this  Society  on  the  3rd  of  February  1848,  I described  a crystalline  body  ob- 

MDCCCXLIX.  3 F 


398 


MR.  STENHOUSE  ON  THE  EXAMINATION  OF  THE 


tained  by  cautiously  pouring  bromine  into  a concentrated  aqueous  solution  of  orcine, 
giving  at  the  same  time  an  analysis  of  the  compound  and  a description  of  its  pro- 
perties. An  abstract  of  the  paper  containing  most  of  these  particulars  was  published 
in  the  Atheneeum  and  Chemical  Gazette  for  Mareh,  and  in  the  London  Philoso- 
phical Magazine  for  April  1848.  Notwithstanding  all  this,  in  the  Comptes  Rendus 
for  August  1848,  Messrs.  Laurent  and  Gerhardt  describe  this  very  compound  with 
exactly  the  same  properties,  and  obtained  in  precisely  the  same  way,  without  so  much 
as  ever  hinting  that  it  had  been  previously  discovered.  Messrs.  Laurent  and  Ger- 
hardt, however,  give  a different  formula  for  the  compound,  which  I am  also  disposed 
to  adopt,  as  on  repeating  my  analysis  of  it  I find  I had  somewhat  over-estimated  the 
amount  of  bromine  contained  in  it,  while  its  other  constituents  were  determined 
correetly  enough.  The  following  are  the  results  of  the  corrected  analysis  of  brom- 
orcine : — 

I.  0'361  grin,  substance  dried  in  vacuo  gave  0*5628  Ag  Br=0*2395  Br  = 66*34  per 
cent.  Br. 

11.  0*3615  gave  0*565  Ag  Br=0*2404  Br=66*50  per  cent.  Br. 

III.  0*281  gave  0*438  Ag  Br=0*1864  Br  = 66*33  per  cent.  Br. 

0*264  substance  dried  in  vacuo,  and  burned  with  chromate  of  lead,  gave  0*227  car- 
bonic acid  and  0*0367  water. 


Brom- orcine. 


Found  numbers. 


Calculated  numbers. 

per  cent. 

I. 

II. 

III. 

14C 

1050*00 

23*27 

23*44 

5H 

62*50 

1*39 

1*54 

3Br 

2998*89 

66*47 

66*34 

66*50 

66*33 

40 

400*00 

8*87 

8*68 

4511*39 

100*00 

100*00 

The  rational  formula  of  brom-orcine  is  therefore  Ci4H5Bi*3  04,  or  oreine  in  which 
three  equivalents  of  hydrogen  are  replaced  by  bromine. 

The  following  is  the  composition  of  anhydrous  orcine  : — 

0*349  grm.  orcine  dried  in  vacuo  over  S03  for  some  weeks,  and  burned  with  chro- 
mate of  lead,  gave  0*8675  carbonic  acid  and  0*205  water. 


Calculated  numbers. 

C 14  1050*0 

per  cent. 

6775 

Found  numbers 
67*80 

H 8 

99*8 

6*44 

6*52 

0 4 

400*0 

25*82 

25*68 

1549*8 

100*00 

100*00 

Beta-orcine. 

The  London  Philosophical  Magazine  for  July  1848  contains  a description  of  a 
compound  to  which  I have  given  the  name  of  beta-orcine,  from  the  great  analogy 


PROXIMATE  PRINCIPLES  OF  SOME  OF  THE  LICHENS. 


399 


which  it  bears  to  orcine  both  in  the  mode  of  its  formation  and  in  most  of  its  pro- 
perties. Beta-orcine  may  be  obtained  by  two  processes ; either  by  destructively  di- 
stilling usnic  acid,  or  by  acting  on  that  body  by  alkalies.  It  crystallizes  very  beauti- 
fully in  four-sided  prisms  surmounted  at  either  end  by  well-defined  four-sided  pyra- 
mids. It  is  very  soluble  in  water,  alcohol  and  ether.  Its  solutions  are  perfectly 
neutral.  Its  crystals  are  hard  and  brittle,  have  a brilliant  lustre,  and  are  usually 
from  an  inch  to  three  quarters  of  an  inch  long. 

Beta-orcine  has  a faintly  sweetish  taste.  In  the  course  of  a few  minutes  it  assumes 
with  ammonia  a beautiful  blood-red  colour,  which  on  standing  becomes  deeper. 
Beta-orcine  is  therefore  much  more  rapidly  acted  on  by  ammonia  than  ordinary 
orcine.  The  smallest  portion  of  beta-orcine  instantly  strikes  a bright  blood-red 
colour  with  a solution  of  hypochlorite  of  lime ; just  as  alpha  and  beta  orsellic  acids, 
erythric,  lecanoric  and  gyrophoric  acids  do  with  the  same  reagent.  Ordinary  orcine, 
on  the  other  hand,  yields  a violet  purple  colour  with  hypochlorite  of  lime.  The 
formula  which  I now  propose  for  beta-orcine  is  C^g  Hjo  O4,  that  of  orcine  being 
C44H8O4.  I have  inserted  this  short  notice  of  beta-orcine  merely  to  complete  the 
series  of  this  class  of  bodies. 

Quint  onitr  at  ed-erythromannite. 

In  the  former  paper  on  the  lichens,  already  so  often  referred  to,  I have  described 
under  the  name  of  pseudo-orcine,  a remarkably  beautiful  crystalline  body,  which  is 
obtained  by  boiling  either  picro-erythrin  or  erythric  acid  itself,  with  an  excess  of  lime 
or  baryta.  I have  subsequently  been  induced  to  change  the  name  of  this  compound 
to  that  of  erythromannite,  as  indicating  at  once  its  origin  and  its  most  characteristic 
properties.  It  was  mentioned  in  the  previous  paper  that  I then  regarded  erythro- 
mannite as  very  analogous  to  rnannite  in  its  properties,  and  from  an  experiment  I 
have  recently  made  this  conjecture  has  received  very  ample  confirmation.  About 
two  years  ago,  Messrs.  Flores  Domonte  and  Menard  obtained  a curious  detonating 
compound  by  dissolving  rnannite  in  fuming  nitric  acid  kept  carefully  cooled,  and 
then  adding  an  equal  bulk  of  sulphuric  acid  to  the  solution.  The  compound,  which 
is  crystalline,  is  deposited  on  the  cooling  of  the  liquid.  It  is  first  washed  wdth  cold 
water,  in  which  it  is  insoluble,  to  free  it  from  adhering  acid,  and  then  dissolved  in 
boiling  spirits  of  wine,  out  of  which  it  crystallizes  in  long  silky  needles.  Mannite- 
quintinitrique,  as  these  French  chemists  have  called  it,  possesses  the  remarkable 
property  of  detonating  so  violently  when  struck  with  a hammer,  that  M.  Sobrero 
has  proposed  employing  it  for  the  manufacture  of  percussion  caps  instead  of  fulmi- 
nate of  mercury. 

As  might  naturally  have  been  expected,  from  the  great  similarity  in  composition 
and  properties  which  rnannite  and  erythromannite  have  to  each  other,  erythromannite, 
when  treated  with  fuming  nitric  acid,  also  yields  a nitrated  compound  perfectly  ana- 
logous to  quintonitrated-mannite.  In  order  to  prepare  this  compound  certain  pre- 

3 F 2 


400 


MR.  STENHOUSE  ON  THE  EXAMINATION  OF  THE 


cautions  are  requisite,  which  I shall  shortly  describe.  Erythromannite  in  the  state 
of  powder  is  to  be  slowly  added  to  a quantity  of  fuming  nitric  acid  kept  at  a low 
temperature.  The  erythromannite  rapidly  dissolves,  while  considerable  heat  is 
evolved.  So  soon  as  a complete  solution  is  effected,  rather  more  than  an  equal  bulk 
of  sulphuric  acid  must  be  cautiously  added  to  the  solution.  When  the  mixture  has 
stood  for  half  an  hour,  it  becomes  filled  with  a magma  of  crystals.  These  are  collected 
in  a funnel  stopped  with  asbestos,  and  are  left  to  drain.  They  are  next  washed  with 
cold  water,  in  which  they  are  insoluble,  till  all  adhering  acid  is  removed,  and  then 
dried  by  pressure  between  sheets  of  blotting-paper.  The  compound  is  then  boiled 
with  moderately  strong  spirits,  in  which  it  readily  dissolves,  and  on  the  cooling  of 
the  liquid  it  is  deposited  in  large  flat  crystals  resembling  those  of  benzoic  acid,  only 
larger,  and  exhibiting  a great  deal  of  a mother-of-pearl  lustre. 

It  might  naturally  be  supposed  that  this  compound  would  also  be  formed  by  dis- 
solving erythromannite  in  a mixture  of  equal  parts  of  fuming  nitric  and  sulphuric 
acids,  and  that  it  would  be  thrown  down  by  adding  a sufficient  quantity  of  water. 
This  is  not  the  case,  however,  either  with  it  or  with  the  mannite  compound,  which 
can  only  be  procured  in  the  way  already  described,  by  employing  the  nitric  acid  first, 
and  precipitating  the  nitrated  compounds  by  adding  the  sulphuric  acid  afterwards. 
The  solutions  of  nitrated  erythromannite  are  quite  neutral  to  test-paper.  When 
nitrated  erythromannite  is  heated  to  61°  C.  it  melts,  but  recrystallizes  immediately 
when  cooled  a few  degrees  below  that  temperature ; when  strongly  heated,  it  takes 
fire  and  burns  with  a gentle  deflagration.  When,  however,  the  dried  erystals  are 
mixed  with  a little  sand  and  are  struck  with  a hammer,  they  detonate  with  great 
violence.  This  reaction  clearly  shows  the  close  analogy  that  subsists  between  nitrated 
erythromannite  and  quintonitrated  mannite,  which  will  appear  still  more  distinctly 
on  comparing  the  results  of  their  analysis.  As  however  this  relation  equally  subsists 
between  mannite  and  erythromannite,  I shall  first  subjoin  the  formulse  and  analyses 
of  these  two  bodies  also,  so  that  the  intimate  relation  existing  among  these  four 
compounds  may  be  rendered  more  distinctly  perceptible. 

0'4702  grm.  erythromannite,  dried  in  vacuo  and  ignited  with  chromate  of  lead,  gave 
0'679  carbonic  acid  and  0*355  water. 


Erythromannite . 

per  cent. 

Found. 

Mannite. 

per  cent. 

lie  825 

39*29 

39*36 

C 12  900*0 

39*57 

14  H 175 

8*33 

8*60 

H14  174*7 

7-67 

no  1100 

52*38 

52*04 

0 12  1200*0 

52*76 

2100 

100*00 

100*00 

2274*7 

100*00 

The  rational  formula  of  mannite  is Hi4  0|2' 

The  rational  formula  of  erythromannite  is 

Mannite  therefore  only  differs  from  erythromannite  by  containing  one  equivalent 
more  of  carbonic  oxide. 


PROXIMATE  PRINCIPLES  OF  SOME  OF  THE  LICHENS. 


401 


I.  0*3755  grm.  quintonitrated-erythromannite,  dried  in  vacuo  and  burned  with 
chromate  of  lead,  gave  0*228  carbonic  acid  and  0*083  water. 

II.  0*394  grm.  quintonitrated-erythromannite,  dried  in  vacuo  and  burned  with 
chromate  of  lead,  gave  0*241  carbonic  acid  and  0*089  water. 

10  tubes  gave  329  measures  of  mixed  gases  consisting  of  227  carbonic  acid  and 
102  measures  nitrogen,  or  carbonic  acid  gas  in  the  proportion  of  eleven  to  five 
nitrogen. 

Quintonitrated-erythromannite.  Found.  Quintonitrated-mannite. 


Calculated  numbers. 

per  cent. 

I. 

11. 

Calculated  numbers. 

per  cent. 

lie  825 

16*75 

16*56 

16*68 

12  c 900*0 

17-66 

9H  112 

2*27 

2*46 

2*50 

9H  112*3 

2*21 

5N  885 

17-98 

17*83 

17-83 

5N  885*0 

17-36 

31  0 3100 

63*00 

63*15 

62*99 

32  0 3200*0 

62*77 

4922 

100*00 

100*00 

100*00 

5097-3 

100*00 

The  rational  formula  of  quintonitrated-erythromannite  is  therefore  Hy  Og 
-f-5N05  = erythromannite,  in  which  five  equivalents  of  water  are  replaced  by  five 
equivalents  of  nitric  acid,  and  corresponding  exactly  in  this  respect  with  quinto- 
nitrated-mannite, in  which  five  equivalents  of  water  are  also  replaced  by  five  equi- 
valents of  nitric  acid.  I conclude  by  subjoining  the  formulae  of  these  four  com- 
pounds, which  only  differ  from  each  other  by  one  equivalent  of  carbonic  oxide,  that 
so  their  mutual  relations  may  be  seen  at  a glance. 

Mannite  ....  0^2  H14  Oi2.  Quintonitrated-mannite  ....  Hg  O7-I-5NO5. 

Erythromannite  C44  H14  O44.  Quintonitrated-erythromannite  C14  Hy  Og-j-fiNOg. 


Glasgow,  \2th  February  1849. 


I, , 


■s  \ 


• '•^>‘-  -’wpi 


1 


.^'3 


att/r  > i.»-’ 

^V■  ■■’|‘■  i>iifcljiAs||(). , .."i*Ji::v/  !.^r:''''.‘  i-'-i  ijf  -Mau  ho'.  :,  Mvi  i<‘: 

hm,. h v'"  w 

•..v;i-:«).,.i»#*-i(^Alrt<..i':vf  S!th;=- 

Vv  ' ' '^'<'  ''-W.^f  ■ '■' "o  .?.t  ■ ■ ' ■■-  ' .f'i  > 


' • . ' .•  .V  • •'  ,VL:>  ^• 


u . '.  ' \ 

■ hi;-  ■ ' 

>f  y 

; 

y ij ' j - ' 

) ,j  l ;,'  t •>■■ 

0.  ' 

i\  ‘ 

. vr  /.;  ?':;■)»■ 

r.y-^1  t'XAYy.  Vi  ri 


...  . . 


, ,1  ^ 


- ,•  ih.  jr  ■ '7 

Ml  * • '■  ■'  ^ 

^ ■'V  .' 

,„-  , ,,  .s;  y ■ 'V.’ Uil-tdaiBi:*^ 


■ '"■,  ,l.t 


|:V  ^ 


',Vl,4)>' 


<7  ^-t-.  k'i'^it'’'- 


*1 


. -V,. 


■r^h-"  ;:?W 


Lv  ,s'V'  '■'.'! 


■■,  '■  " S'—  ' J 

ys,  "miy-A 


Uyh^h' 


'•:.  .-^v. 


J' 


. 4^<®' 


.,  ,y,;  • -j''  ■'  ^■»%V  V':il 

■ ''m 


'A‘y 


xmm 


^■:Vi 


' r 


/ ' r ’■  :m 

$1. 


[ 403  ] 


XXL  On  the  Structure  of  the  Dental  Tissues  of  Marsupial  Animals,  and  more  especially 
of  the  Enamel.  By  John  Tomes,  Surgeon-Dentist  to  the  Middlesex  Hospital. 
Communicated  by  R.  E.  Grant,  M.D.,  F.R.S.,  Professor  of  Comparative  Anatomy 
and  Zoology  at  University  College. 


Received  June  21, — Read  June  21,  1849. 


My  dear  Dr.  Grant, 

On  making  microscopic  examinations  of  the  teeth  of  one  or  more  species  of  the 
several  families  of  the  marsupial  animals,  the  skulls  of  which  you  kindly  placed  at 
my  disposal,  I found  some  peculiarities  of  structure,  which  so  far  as  I know  have  not 
hitherto  been  recognised,  and  which  will  I think  be  found  to  constitute  a pretty  con- 
stant character  in  the  teeth  of  this  order  of  quadrupeds.  It  is  my  present  purpose 
to  describe  these  peculiarities,  and  should  the  communication  seem  sufficiently  inter- 
esting and  important  to  engage  the  attention  of  the  Royal  Society,  my  debt  of  grati- 
tude, already  great,  will  be  rendered  yet  greater  by  your  lending  your  name  for  its 
presentation. 

Professor  Owen,  in  his  Odontography  (p.  397),  when  treating  on  the  structure  of 
the  marsupial  teeth,  says,  The  dentine,  enamel,  and  cement  of  the  teeth  of  marsupial 
animals,  present  the  usual  microscopic  characters  of  these  tissues  in  Mammalia.” 
My  researches  have  led  me  to  a different  conelusion.  The  enamel  presents  a very 
strongly-marked  peculiarity,  common  (so  far  as  I have  examined),  with  one  excep- 
tion only,  to  all  marsupial  teeth,  and  present  only  in  a very  limited  number  of  other 
mammalian  teeth.  I have  hitherto  found  it  only  in  the  British  Shrews,  the  Hyrax, 
and  in  the  molar  teeth  of  the  Jerboa. 

The  main  peeuliarity  to  which  I allude,  is  that  the  greater  number,  if  not  all,  of 
the  dentinal  tubes  are  continued  into,  and  constitute  a considerable  portion  of  the 
enamel.  I have  in  another  place*  pointed  out  that  in  the  human  teeth  the  dentinal 
tubes  are  in  small  numbers,  and  occasionally  only  continued  for  a short  distance  into 
the  enamel ; and  the  same  may  be  said  of  many  other  teeth.  In  these  instances  how- 
ever the  condition  is  rudimentary  only,  but  in  the  marsupial  teeth  the  development 
of  the  tubes  in  the  enamel  is  as  perfect  as  in  the  dentine  itself.  It  is  not  difficult  to 
suppose  that  a portion  of  the  columns  of  cells,  which  constitute  the  enamel  pulp,  may 
become  developed  into  tubes  continuous  with  those  formed  by  the  columns  of  cells 
in  the  adherent  dentinal  pulp,  instead  of  being  converted  into  solid  enamel  fibres  which 


* Lectures  on  Dental  Physiology  and  Surgery,  p.  35. 


404 


MR.  TOMES  ON  THE  STRUCTURE  OF 


occurs  in  the  majority  of  teeth  ; and  this  no  doubt  does  happen  in  the  marsupial 
teeth,  and  also  in  some  few  others.  Indeed  in  all  teeth  the  enamel  fibre  is  in  an  early 
stage  of  formation  partially  tubular*. 

I will  now  proceed  to  describe  the  teeth  in  those  species  of  marsupials  that  I have 
examined  ; for  I find  many  minor  points  of  dissimilarity,  by  which,  on  careful  com- 
parison, the  teeth  of  allied  species  may  be  distinguished  the  one  from  the  other. 

I may  remark,  however,  before  doing  so,  that  the  enamel  presents  other  points  of 
peculiarity,  though  less  apparent,  than  its  tubularity.  In  many  marsupial  teeth  the 
enamel  is  studded  with  small  cells,  often,  but  by  no  means  always,  arranged  in  con- 
tour lines.  Then  again  the  fibres  are  in  many  teeth  so  intimately  united  to  each 
other  that  their  individuality  is  lost,  and  this  occurs  in  most  teeth  in  some  parts,  so 
that  the  dimensions  of  the  fibres  at  such  points  cannot  be  taken. 

Macropus giganteus. — In  this  animal  the  differences  in  the  dental  tissues  composing 
the  incisor  and  molar  teeth,  are  chiefly  confined  to  the  number  of  curves  described 
by  the  enamel  fibres  and  tubes.  I shall  therefore  for  the  present  restrict  my  descrip- 
tion to  a transverse  section  of  a lower  incisor  through  the  part  most  thickly  coated 
with  enamel. 

The  dentinal  tubes  radiate  from  the  pulp-cavity  with  numerous  gentle  secondary 
curves,  and  when  pursuing  the  latter  third  of  their  course  before  entering  the  enamel, 
give  off  numerous  short  fine  branches.  When  near  the  enamel  the  small  branches 
suddenly  cease  to  be  given  off,  and  the  parent  tubes,  either  with  or  without  bifur- 
cating, enter  the  enamel.  The  absence  of  the  minute  lateral  tubules  renders  the  tooth 
more  transparent  at  these  than  in  the  neighbouring  parts.  On  entering  the  enamel 
the  tubes  dilate  into  more  or  less  oval  or  conical  cells,  from  whence  they  are  con- 
tinued, and  follow  in  delicate  undulations  the  course  of  the  enamel  fibres,  some  few 
giving  off  on  their  way  one  or  two  branches.  They  gradually  diminish  in  size  till 
they  are  eventually  lost  near  the  surface  of  the  enamel,  either  from  their  own  minute- 
ness or  from  their  entering  small  opaque  cells,  which  are  common  near  the  outer  sur- 
face of  this  texture,  Plate  XXXV.  fig.  1 A,  the  dentine  ; B,  the  enamel.  The  enamel 
fibres  in  the  thickest  part  of  the  tooth  are  subject  in  their  course  outwards  to  four,  five, 
and  sometimes  to  even  six  flexures,  fig.  2 B.  As  they  arise  from  the  periphery  of  the 
dentine,  they  proceed  upwards  in  a tolerably  straight  line  towards  the  cutting  margin 
of  the  tooth ; they  then  turn  downwards  at  an  angle  of  ninety  degrees  with  their  first 
course,  and  after  advancing  about  as  far  in  the  second  as  they  did  in  the  first  line, 
they  describe  several  lesser  flexures  having  similar  angles  to  the  first.  When  within 
two-fifths  of  their  termination  on  the  surface,  the  enamel  fibres  take  a straight  and 
parallel  course  at  right  angles  with  the  surface  of  the  tooth. 

As  the  coating  of  enamel  becomes  thinner,  both  towards  the  cutting  edge  and  at 
the  lower  part  of  the  tooth,  the  lesser  curvatures  of  the  fibres  are  lost,  and  the  direc- 
tion of  the  first  large  flexure  is  reversed ; so  that  the  fibres  proceed  first  downwards 

* Lectures  on  Dental  Physiology  and  Surgery,  p.  102. 


THE  TEETH  OF  MARSUPIAL  ANIMALS. 


405 


and  then  upwards.  Near  the  surface  numerous  small  opaque  cells  are  found  irregularly 
interspersed  amongst  the  enamel  fibres,  or  arranged  in  contour  lines. 

In  the  molar  teeth  the  enamel  fibres  which  arise  from  the  depressions  on  the  mas- 
ticating surface  describe  several  curves,  while  those  from  the  sides  of  the  tooth  and 
of  the  tubercles  have  but  one  flexion,  and  even  this  is  lost  where  the  enamel  thins 
previous  to  its  termination  on  the  neck  of  the  tooth. 

The  tubes  here,  as  in  the  incisors,  accompany  the  fibres,  but  those  which  arrive 
near  the  apex  of  the  tubercles  wind  round  in  a spiral  course,  fig.  3.  When  the  enam.el 
becomes  thin  previous  to  its  cessation,  the  tubes  are  less  abundant ; and  at  its  termina- 
tion few,  if  any,  are  seen  in  this  or  any  of  the  marsupial  teeth.  When  speaking  of 
the  enamel  in  the  incisors  of  the  Kangaroo,  Professor  Owen  says*,  “The  fibres  of  the 
enamel  which  invest  the  crown  of  the  large  lower  incisor  are  likewise  unusually 
minute;  viewed  in  a transverse  section,  as  in  plate  102  ee,  they  describe  an  abrupt 
curve  at  their  commencement,  and  then  proceed  in  a nearly  straight  course  to  the 
surface;  but  at  the  trenchant  margins  of  the  tooth  their  course  is  curved,  and  they 
decussate  one  another,  as  represented  in  the  figure-f'.  Some  of  the  enamel  lines  at 
this  part  seem  to  be  as  fine  as  the  dentinal  tubes.”  Professor  Owen  has  evidently 
seen  the  enamel  tubes  in  this  tooth,  but  from  some  cause  has  failed  to  recognise  them 
as  such.  In  the  same  page  he  says,  “The  terminal  branches  of  the  (dentinal)  tubuli 
open  into  minute  irregular  cells,  forming  a thin  boundary  layer  between  the  dentine 
and  enamel.”  These  cells  are  certainly  not  between  the  dentine  and  enamel  in  any 
of  the  sections  I have  made,  but  are  distinctly  enough  visible  in  the  enamel,  and  form 
part  of  the  continuous  dentinal  and  enamel  tubes. 

In  conducting  the  examination  of  this  tooth  and  of  the  teeth  I am  about  to  describe, 
I have  made  at  least  half-a-dozen  sections,  taken  from  different  parts  and  in  different 
directions  of  the  tooth  for  the  purpose  of  avoiding  error. 

Professor  Owen  states,  that  the  dentinal  tubes  are  the  ixWolli  of  joch  in  dia- 
meter. In  the  specimens  I have  examined,  they  have  averaged  i o.ooofh  of  an  inch  at 
their  commencement  at  the  pulp-cavity,  have  gradually  diminished,  and  on  entering  the 
enamel  have  not  exceeded  the  yo';l)~oofh  of  an  inch.  On  dilating  they  reach  e^^eth, 
and  again  contract  to  the  2^07^0^^  of  an  inch,  from  which  they  are  reduced  gradually 
fo the  30,000th  and  are  lost. 

The  enamel  fibres  measure  oeVeth  and  are  cylindrical  or  oval  in  their  transverse 
section.  The  dentinal  tubes  in  the  root  of  the  teeth  vary  in  diameter  indifferent 
parts  of  their  course,  and  are  oval  in  a transverse  section.  At  their  commencement 
they  are  the  iVsT^t,  but  at  the  middle  of  their  course  they  reach  the  -gi^th  of  an 
inch  in  diameter,  in  addition  to  which  they  are  subject  to  short  local  dilatations.  In 
this  part  of  the  tooth  branches  are  given  off  almost  from  the  commencement  of  the 

* Odontography,  p.  397. 

f Plate  102,  fig.  1.  “ One-half  of  a transverse  section  of  the  lower  incisor  of  a Kangaroo  (Macropus  major), 
showing  the  course  of  the  dentinal  tubes  at  d and  the  fine  fibres  of  the  thick  enamel  at  e.” 

3 G 


MDCCCXLIX. 


406 


MR.  TOMES  ON  THE  STRUCTURE  OF 


tubes ; these  recurve  and  present  their  convexities  towards  the  outer  surface  of  the 
tooth. 

Near  the  surface  the  dentinal  tubes  break  up  into  an  infinite  number  of  delicate 
branches,  resembling  tufts  of  fine  moss,  effecting  at  the  same  part  innumerable  ana- 
stomoses. At  and  near  the  extremity  of  the  fang,  shoi’t  branching  dentinal  tubes  are 
interspersed  with  cemental  cells,  but  higher  up,  towards  the  crown  of  the  tooth,  the 
cement  and  dentine  are  separated  by  a well-defined  line  of  demarcation,  across  which 
a few  only  of  the  tubes  advance  to  join  the  branches  of  the  neighbouring  cemental 
cells. 

Near  the  neck  of  the  tooth  the  cemental  cells  are  often  altogether  wanting  in 
branches,  and  approach  a circular  form. 

Hypsiprymniis  minor  and  pemcillatus. — The  teeth  of  these  animals  resemble  very 
closely  in  structure  those  of  the  Kangaroos.  In  the  incisors,  the  enamel  being  less 
thick,  present  but  one  curve,  and  that  in  the  direction  of  the  axis  of  the  tooth. 

In  Hyp.  penicillatus,  the  dentinal  tubes,  on  entering  the  enamel,  dilate  into  irre- 
gularly oval  or  circular  cells,  measuring  about  i 0,000th  of  ao  inch  in  diameter ; they 
then  suddenly  contract  to  goiVooth,  and  follow  the  course  of  the  enamel  fibres  to  near 
the  surface ; then  some  few  bend  to  a right  angle  with  their  original  course  and  ter- 
minate in  a point,  their  terminal  course  being  directed  towards  the  root  of  the  tooth, 
fig.  4,  The  fibres  of  the  enamel  measure  7 smooth  of  an  inch  in  diameter. 

The  dentinal  tubes  at  their  commencement  at  the  pulp-cavity  measure  the  12000^^^ 
and  at  the  point  where  they  enter  the  enamel  the  — 4— -th  of  an  inch. 

In  Hypsiprymnus  minor,  the  dentinal  tubes,  on  entering  the  enamel,  often  do  not 
dilate  at  all,  and  when  they  do,  the  dilatation  is  continued  for  some  little  distance 
with  an  irregular  outline.  Hence,  on  accurate  comparison,  the  teeth  of  the  one 
species  of  Hypsiprymnus  may  be  distinguished  from  those  of  the  other. 

Phascolomys  Womhat. — The  teeth  of  this  interesting  marsupial  are  remarkable  for 
the  complete  absence  of  tubes  in  the  enamel.  The  dentinal  tubes  cease  at  the  line 
of  junction  of  the  dentine  with  the  enamel,  and  in  no  case  pass  across  into  the  enamel. 
The  fil)res  of  the  latter  texture  are  clear  and  transparent ; and  arising  from  the  peri- 
pheral surface  of  the  dentine,  after  presenting  one  or  two  slight  undulations,  arrive 
at  the  surface  of  the  enamel,  which  in  the  incisor  teeth  is  invested  with  a thin  layer 
of  cement.  The  enamel  fibres  measure  about  the  yyg-oth  of  an  inch  in  diameter. 
Their  course  is  not,  as  regards  each  other,  everywhere  parallel ; on  the  contrary,  at 
certain  points  intervals  will  be  left  by  their  divergence,  which  are  filled  up  by  sup- 
plementary fibres ; then  again  bundles  of  fibres  converge  and  cross  each  other.  I 
have  failed  to  observe  the  transverse  striae  mentioned  by  Prof.  Owen*.  The  fibres 
have  sometimes  a slightly  irregular  outline,  which  gives  an  appearance  of  unequal 
dimensions  to  different  parts  of  the  same  fibre,  and  not  unfrequently  longitudinal 
central  lines  may  be  seen,  like  the  persistent  nuclei  of  the  developmental  cells. 

* Odontography,  page  398. 


THE  TEETH  OF  MARSUPIAL  ANIMALS. 


407 


The  dentinal  tubes  are,  at  the  pulp-cavity,  about  the  of  an  inch  in  dia- 

meter, and  at  the  peripheral  ends  so.ooo^h  of  an  inch.  The  tubes,  as  they  leave  the 
pulp-cavity,  advance  upwards  towards  the  surface  of  the  tooth,  but  in  the  latter  part 
of  their  course  they  bend  outwards,  and  thus  describe  large  curves,  the  convexities  of 
which  are  directed  towards  the  masticating  surface.  Until  within  the 
inch  of  the  enamel  the  dentinal  tubes  give  off  very  few  branches,  but  when  they  have 
arrived  at  that  point,  and  for  a short  distance  onward,  they  give  off  numerous  tubules 
which  form  a dense  meshwork  of  tubes  in  a contour  line  with  the  enamel,  fig.  5. 

Professor  Owen,  in  the  work  already  referred  to — the  standard  work  on  Odonto- 
graphy in  our  language, — mentions  that  medullary  canals  are  prolonged  into  the  sub- 
stance of  the  dentine,  and  also  that  many  of  the  dentinal  tubes  terminate  in  cells  on 
the  periphery  of  the  dentine.  Of  this  I have  now  to  speak. 

Out  of  this  meshwork  of  branching  and  anastomosing  tubes  a few  are  continued 
into  a comparatively  clear  space  about  the  of  an  inch  broad,  and  terminate 

either  in  irregular  cells  which  vary  from  the  to  the  1 s.ooolh  of  an  inch  in 

diameter,  or  by  anastomosis.  None  however  cross  into  the  enamel.  That  portion  of 
the  tooth  which  lies  towards  the  mouth  is  not  invested  with  enamel,  but  is  covered  by 
a thin  layer  of  cement,  between  which  and  the  dentine  there  is  no  distinct  line  of 
demarcation.  Into  the  cells  of  this  run  the  terminal  branches  of  the  dentinal  tubes. 
The  cement  is  continued  over  the  surface  of  the  enamel  in  a layer  of  about  the 
of  an  inch  in  thickness,  and  this  is  tenanted  by  a single  line  of  cells. 

These  teeth  closely  resemble,  as  well  in  structure  as  in  external  form,  those  of  the 
Rodents,  and  especially  the  Hare  and  Rabbit. 

Phalangista  vulpina. — The  dentinal  tubes  of  the  molar  teeth  of  this  creature  arise 
at  the  pulp-cavity,  with  a diameter  of  about  the  10,0 00th  of  an  inch,  and  pursue  a 
slightly  undulating  course  until  they  have  accomplished  two-thirds  of  their  whole 
distance ; they  then  bend  downwards  from  the  crown,  and  give  off  innumerable 
minute  tubules.  When  within  a short  distance  of  the  enamel  they  dichotomize  once 
or  twice,  and  enter  that  structure  with  a diameter  of  about  the  3o,-o~6uth  of  an  inch, 
fig.  6. 

On  passing  into  the  enamel  the  tubes  occasionally  dilate  into  an  oval  or  oblong 
cell  of  from  the  ysVoth  to  the  ro.ooot^^  of  inch  in  diameter,  but  far  more  com- 
monly they  undergo  no  dilatation.  Others  again  dilate  into  an  oval  or  long  cell. 
When  they  have  passed  half  or  two-thirds  through  the  enamel,  some  few  divide  once 
or  twice  into  two  branches.  After  following  an  undulating  course  until  near  the 
surface  of  the  tooth,  they  terminate  in  small  cells  or  become  imperceptibly  minute. 
The  tubes  in  the  enamel  have  a diameter  varying  from  the  Ts.oooth  to  the  -2  5.0 00 th  of 
an  inch. 

The  dentinal  tubes,  near  their  commencement  at  the  pulp-cavity,  in  about  the 
middle  part  of  the  fang,  commonly  reach  a diameter  of  the  of  an  inch.  They 

give  off  branches  during  the  whole  of  their  course,  and  terminate  in  a dense  anasto- 

3 G 2 


408 


MR.  TOMES  ON  THE  STRUCTURE  OF 


mosing  plexus  of  tubes,  from  which  many  pass  to  the  cells  of  the  cement ; hence 
these  two  tissues  are  not  separated  from  each  other  by  a strongly-marked  line  of 
demarcation,  such  as  obtains  in  some  other  teeth  of  marsupial  animals. 

Petaiiriis  taguanoides. — The  molar  teeth  of  this  interesting  animal,  though  pos- 
sessing the  marsupial  characteristic  strongly  marked,  yet  are  so  different  under  the 
microscope  from  those  I have  already  described  as  to  be  recognised  at  first  sight. 
The  dentinal  tubes  at  their  commencement  at  the  pulp-cavity  have  a diameter  not 
exceeding  the  of  an  inch.  They  follow  a slightly  undulating  course  to  about 

two-thirds  of  their  length  ; they  then  make  one  large  curve,  the  concavity  of  which  is 
usually  directed  towards  the  crown  of  the  tooth.  At  no  part  of  their  course  do  the 
dentinal  tubes  of  the  crown  give  off  branches  until  they  arrive  at  the  enamel ; then  a 
few,  and  a few  only,  divide  into  two  branches,  and  are  continued  into  that  tissue. 
The  tubes,  on  entering  the  enamel,  make  a small  curve  downwards,  corresponding  in 
direction  to  that  in  the  dentine  just  described;  they  then  follow  an  upward  course,  and 
are  lost  near  the  surface.  The  tubes  usually  suffer  no  change  of  dimensions  on  passing 
into  the  enamel,  but  generally  keep  a diameter  of  about  eb.oo'olh  of  an  inch,  till  they 
are  lost  in  small  opaque  markings  that  are  common  in  the  enamel  near  its  surface, 
Plate  XXXVI.  fig.  7- 

The  dentinal  tubes  of  the  fangs  of  these  teeth  are  perceptibly  larger  than  those  of 
the  crown,  and  very  commonly  have  a ragged  outline,  or  are  composed  of  lines  of 
cells.  They  give  off  but  comparatively  few  branehes,  and  these  only  near  the  surface 
of  the  fang. 

Ill  the  incisor  teeth  the  dentinal  tubes  branch  more  abundantly  than  in  the  molars, 
and  are  less  frequently  continued  into  the  enamel. 

In  the  fangs  of  the  lower  incisors  the  tubes  are  distinctly  oval  in  section,  having  a 
greater  diameter  of  y^xo  lesser  of  rs^oir-  The  final  large  curve  also  has  its 
convexity  directed  towards  the  crown  of  the  tooth. 

Petaurus  sciureus. — The  structural  characters  of  the  teeth  of  this  animal  closely 
resemble  those  of  P.  taguanoides.  There  are  however  differences  by  which,  on  compari- 
son, the  one  may  be  known  from  the  other.  The  dentinal  tubes  in  their  course  from 
the  pulp-cavity  towards  the  crown  arch  with  the  convexity  directed  upwards;  then 
again  they  give  off  numerous  fine  branches  during  the  latter  third  of  their  course. 
In  the  fangs  they  dichotomize  during  the  latter  half  of  their  length,  but  do  not  form 
the  rich  plexuses  of  tubes  common  in  the  Kangaroos  ; neither  do  the  branches  go  off 
at  a right  angle ; on  the  contrary,  they  follow  much  the  same  course  as  the  parent 
tube.  The  fang  is  plentifully  supplied  with  cement,  which  contains  a few  cells  of  very 
elongated  form,  with  the  long  axis  in  the  direction  of  that  of  the  tooth.  In  addition 
to  these  there  are  great  numbers  of  tubes  placed  parallel  with  each  other,  and  at  right 
angles  with  the  surface  of  the  tooth. 

Dasyurus  ursinus. — The  dentinal  tubes  of  the  crown  of  the  tooth  advance  at  a right 
angle  with  the  surface  of  the  pulp-cavity.  Those  which  form  the  upper  part  of  the 


THE  TEETH  OF  MARSUPIAL  ANIMALS. 


409 


crown  proceed  upwards,  then  in  a large  curve  bend  outwards,  and  when  within  the 
x^o^th  of  an  inch  of  the  enamel  give  off  an  abundance  of  short  fine  tubules,  and 
when  so  doing  turn  upwards,  having  but  few  previously,  and  none  at  all  until  within 
half-way  of  the  enamel.  On  entering  the  enamel  they  again  make  a small  curve 
downwards,  give  off  occasional  branches,  and  make  numerous  short  deflections 
downwards,  and  after  advancing  through  about  two-thirds  of  the  thickness  of  the 
enamel  are  lost,  fig.  8. 

The  tubes  at  the  pulp-cavity  measure  about  io,ooo4h  of  an  inch  in  diameter,  and 
on  entering  the  enamel  ^6  Qooth  of  an  inch  ; when  within  the  enamel  they  increase  to 
about  the  20,000th,  and  gradually  diminish  till  they  become  invisible,  or  are  lost  in 
small  cells.  On  the  lingual  surface  of  the  tooth,  the  tubes  in  this,  as  in  many  other 
marsupial  teeth,  commence  by  small  cells. 

The  dentinal  tubes  of  the  fangs  are  lost  in  the  cement,  between  which  and  the  den- 
tine there  is  no  strongly-marked  line  of  demarcation.  The  cemental  cells  are  large, 
elongated  in  figure,  and  have  many  and  large  tubules. 

In  the  molar  teeth  of  Dasyurus  macrourus  the  dentinal  tubes  branch  more  sparingly, 
and  on  entering  the  enamel  are  not  subject  to  the  same  degree  of  deflection,  though 
possessed  of  the  same  general  character  as  those  seen  in  the  D.  ursinus ; neither  do 
they  suffer  any  enlargement  in  the  first  part  of  their  course,  as  is  common  in  the  last- 
mentioned  tooth,  fig.  9. 

The  cemental  cells  are  more  simple  in  form,  and  the  dentine  and  cement  are  sepa- 
rated by  a well-marked  line  of  junction,  except  at  the  apex  of  the  fang,  where  the 
cement  is  reflected  for  a short  distance  up  the  canal. 

In  the  canine  teeth  of  this  animal  a considerable  portion  of  the  lower  end  of  the 
fang  is  made  up  of  cement.  In  the  concave  lingual  surface  of  the  crown  the  enamel 
is  thin,  and  the  tubes  frequently  commence  in  small  cells.  The  dentinal  tubes  give 
off  small  branches  during  the  greater  part  of  their  course,  and  when  close  to  the 
enamel  occasionally  turn  upward  and  dilate  into  elongated  cells. 

Thylacinus  cynocephalus. — The  teeth  of  this  creature  have  a strong  family  resem- 
blance to  those  of  the  Dasyuri  last  described.  There  are  however  minute  points  of 
difference.  The  dentinal  tubes,  in  addition  to  giving  off  minute  short  pilose  branches, 
on  nearing  the  enamel  divide  into  several  large  branches,  fig.  10  A.  They  are  like- 
wise more  disposed  to  dilate  on  entering  the  enamel,  though  many  proceed  without 
marked  increase  of  size.  Then,  again,  the  tubes  are  lost  by  the  time  they  have 
gained  the  inner  fifth  of  the  whole  thickness  of  the  enamel ; and  the  enamel  fibres  are 
more  distinctly  marked  than  in  either  of  the  preceding  species  excepting  the  Wombat, 
thereby  approaching  in  structure  to  the  teeth  of  the  ordinary  carnivora,  fig.  10.  The 
dentinal  tubes,  on  leaving  the  pulp-cavity  to  proceed  towards  the  coronal  surface, 
have  a diameter  of  about  the  xoTo^th  of  an  inch ; on  reaching  the  periphery  the 
ill  i'll®  first  part  of  their  course  in  the  enamel  the  ~2b,Vooth-  Those 
destined  for  the  upper  part  of  the  crown  advance  upwards,  and  then  make  one  large 


410 


MR.  TOMES  ON  THE  STRUCTURE  OF 


bold  curve  outward,  with  the  convexity  directed  upwards  ; in  the  fang  they  make  a 
second  large  curve  with  the  concavity  directed  upwards. 

The  tubes,  when  in  the  enamel,  in  addition  to  a multitude  of  minute  undulations, 
describe  one  large  curve  with  the  concavity  directed  upwards.  They  for  the  most 
part  rapidly  diminish  in  size ; sometimes,  however,  they  dilate  into  small  cells,  and 
again  continue  their  course.  Previous  to  terminating  some  few  give  a number  of 
small  branches  from  their  convex  side  (fig.  10  B),  which  rapidly  diminish  in  size  and 
are  lost.  At  about  the  point  where  the  tubes  are  lost  the  enamel  fibres  become 
tolerably  distinct,  though  with  a somewhat  ragged  indefinite  outline.  Their  diameter 
is  about  the  1 0,000^  of  ioch ; and  they  take  a tolerably  direct  course  outwards. 
I have  stated  that  the  enamel  fibres  of  the  tooth  of  the  Thylacinus  resemble  in  a 
slight  degree  those  of  ordinary  carnivora,  but  the  one  structure  cannot  for  a moment 
be  mistaken  for  the  other,  see  figs.  10  and  11.  Small  cells  are  scattered  through  the 
enamel  of  the  Thylacinus  and  near  the  surface  in  contour  lines. 

The  dentinal  tubuli  of  the  fang  terminate  in  a granular  layer,  which,  excepting 
near  the  extremity  of  the  fang,  is  separated  from  the  cementum  by  a strongly-marked 
boundary  line. 

The  cells  of  the  cementum  have  no  peculiarity ; they  are  arranged  in  linear  series, 
their  long  axes  being  in  the  direction  of  that  of  the  tooth.  The  cement  is  tolerably 
abundant  in  quantity,  and  at  the  apex  of  the  fang  is  pierced  by  canals  for  vessels. 

Didelphis  virginiana. — The  teeth  of  this  species  were  from  the  skull  of  an  old 
animal,  and  though  much  worn  by  use  yet  sufficient  remained  for  my  purpose.  The 
marsupial  characters,  so  far  as  I have  had  the  means  of  observing,  are  strongly  marked. 
The  dentinal  tubes  on  leaving  the  pulp-cavity  have  a diameter  of  about  the  oopth 
of  an  inch.  Those  that  are  destined  for  the  masticating  surface  make  one  or  two  large 
in  addition  to  numerous  gentle  secondary  undulations.  But  all  that  depart  for  the 
sides  of  the  crown  or  the  tubercles,  make  a curve  on  nearing  the  enamel,  the  con- 
cavity of  which  is  directed  upwards,  fig.  12  A.  During  this  part  of  their  course  they 
give  off  from  either  side,  but  more  especially  from  the  convex  side,  numerous  small, 
short,  delicate  branches.  Finally,  they  break  up  into  several  branches,  which  on 
passing  into  the  enamel  preserve  their  dimensions,  the  4^3^!^  RR  inch. 

When  within  the  enamel  the  tubes  advance  to  near  the  surface,  which,  as  the 
enamel  is  not  thick,  is  no  great  distance.  In  their  course,  they  are  subject,  in  addi- 
tion to  small  undulations,  to  one  or  two  deflections,  the  concavities  of  which  are 
directed  towards  the  grinding  surface  of  the  tooth,  and  some  few  give  off  one  or  two 
branches. 

The  cementum  is  abundant,  and  contains  numerous  highly  developed  cells,  which 
give  off  many  branching  and  anastomosing  canaliculi,  which  form  a tolerably  uniform 
meshwork  of  tubes  throughout  the  whole  mass.  The  extremities  of  the  fangs  are 
constituted  of  cement,  through  which  anastomosing  canals  for  vessels  pass  towards 
the  pulp-cavity.  The  cementum  and  dentine,  though  separate  at  some  parts,  at 


fV  f/i/ut,  i/rl  i 


THE  TEETH  OP  MARSUPIAL  ANIMALS. 


411 


Others  pass  into  each  other,  and  are  so  gradually  and  intimately  blended  that  it 
would  be  impossible  to  determine  to  which  tissue  a given  point  belonged. 

The  facts  that  I have  stated  lead,  I think,  to  two  conclusions.  First,  that  the  existence 
of  fully  developed  tubes  in  the  enamel  continuous  with  those  of  the  subjacent  dentine, 
is  common  to  the  teeth  of  at  least  the  great  majority  of  marsupial  animals,  if  not  all, 
excepting  the  Wombat.  And,  secondly,  that  the  enamel  and  dentine  are  so  closely 
related,  that  the  one  should  almost  be  regarded  as  a modification  of  the  other,  rather 
than  as  a tissue  of  a wholly  different  nature. 

The  sections  from  which  the  foregoing  descriptions  have  been  written,  form  part  of 
an  extensive  series  in  my  possession.  The  accuracy  of  the  statements  may  therefore 
at  any  time  be  tested. 

I remain,  my  dear  Sir,  yours  faithfully, 

June  20th,  1849.  John  Tomes. 

To  Robert  E.  Grant,  M.D.,  F.R.S. 


Explanation  of  the  Plates. 

PLATE  XXXV. 

Fig.  1.  A section  from  crown  of  a molar  tooth  of  Macropus  giganteus,  showing  the 
tubes  of  the  dentine  A in  the  latter  part  of  their  course,  and  continued  into 
the  enamel  B,  that  part  only  near  the  dentine  being  shown.  C,  a continu- 
ous dentinal  and  enamel  tube  more  highly  magnified. 

Fig.  2.  A transverse  section  through  the  lower  incisor  of  the  same  animal.  A,  the 
dentine.  B,  the  enamel  in  its  whole  thickness,  showing  the  curves  of  the 
fibres. 

Fig.  3.  The  apex  of  one  of  the  tubercles  from  the  crown  of  a molar  tooth  of  Macropus 
giganteus,  showing  the  whole  thickness  of  the  enamel,  B,  containing  cells 
in  the  contour  lines,  and  showing  also  the  spiral  course  of  the  enamel 
tubes  near  the  apex  of  the  tubercles.  A,  the  dentine. 

Fig.  4.  A longitudinal  section  from  a premolar  tooth  of  Hypsiprymnus  penicillatus, 
showing  the  outer  part  of  the  dentine  A,  and  the  whole  thickness  of  the 
enamel  B,  with  the  tubes  in  each.  C,  the  same  more  highly  magnified. 

Fig.  5.  A longitudinal  section  from  a lower  incisor  of  the  Wombat,  showing  the 
dentine  A,  with  the  manner  of  termination  of  the  dentinal  tubes.  B,  the 
enamel,  and  C,  the  cement. 

Fig.  6.  A longitudinal  section  of  a tubercle  from  a molar  of  Phalangista  vulpina, 
showing  A,  the  dentine,  and  B,  the  enamel  with  their  tnbes. 


412  MR.  TOMES  ON  THE  STRUCTURE  OF  THE  TEETH  OF  MARSUPIAL  ANIMALS. 


PLATE  XXXVI. 

Fig.  7-  A longitudinal  section  from  the  crown  of  a molar  tooth  of  Petaurus  tagua- 
noides,  showing  A,  a portion  of  the  dentine  with  its  almost  branchless 
dental  tubes,  and  B,  the  enamel  in  whole  thickness. 

Fig.  8.  A longitudinal  section  from  the  tooth  of  Dasyurus  ursinus,  showing  a portion 
of  the  dentine  A,  and  the  whole  thickness  of  the  enamel  B,  with  the  tubes  of 
each. 

Fig.  9.  A similar  section  of  the  tooth  of  Dasyurus  macrourus. 

Fig.  10.  A longitudinal  section  of  the  last  molar  from  the  lower  jaw  of  Thylacinus 
cynoceyhalus,  showing  A,  a portion  of  the  dentine,  and  B,  a portion,  but 
not  the  whole  thickness  of  the  enamel. 

Fig.  1 1 . A section  from  the  canine  tooth  of  the  Leopard,  showing  A,  the  peripheral 
part  of  the  dentine,  and  B,  the  enamel.  The  latter  is  typical  of  the  enamel 
of  the  ordinary  carnivora,  the  fibres  of  which  measure  the  so^ooth  of  an 
inch  in  diameter*. 

Fig.  12.  A longitudinal  section  of  a molar  tooth  of  Didelphis  virginiana,  showing  A, 
the  dentine  at  its  termination,  and  B,  the  enamel  in  its  whole  thickness, 
with  the  tubules  in  each  texture. 

* This  figure  is  introduced  to  show  the  diflferences  between  the  enamel  in  the  ordinary  carnivora  and  in  the 

marsupial  carnivora. 


Il'll',/,,/.  M'. 


L 413  ] 


XXII.  On  the  Anatomy  and  the  Affinities  of  the  Family  of  the  Medusae.  By  Thomas 
Henry  Huxley,  Esq.,  Assistant-Surgeon  of  H.M.S.  Rattlesnahe,  now  engaged  in 
a Surveying  Voyage  conducted  by  Capt.  Stanley  on  the  Coasts  of  Australia  and 
New  Guinea.  Communicated  by  the  Bishop  of  Norwich,  F.R.S. 


Received  March  29, — Read  June  21,  1849. 

1.  Perhaps  no  class  of  animals  has  been  so  much  investigated  with  so  little 
satisfactory  and  comprehensive  result  as  the  family  of  the  Medusce,  under  which 
name  I include  here  the  Medusce,  Monostomatae  and  Rhizostomidce ; and  this,  not  for 
the  want  of  patience  or  ability  on  the  part  of  the  observers  (the  names  of  Ehrenberg, 
Milne -Edwards,  and  He  Blainville,  are  sufficient  guarantees  for  the  excellence  of 
their  observations),  but  rather  because  they  have  contented  themselves  with  stating 
matters  of  detail  concerning  particular  genera  and  species,  instead  of  giving  broad 
and  general  views  of  the  whole  class,  considered  as  organized  upon  a given  type,  and 
inquiring  into  its  relations  with  other  families. 

2.  Tt  is  my  intention  to  endeavour  to  supply  this  want  in  the  present  paper — 
with  what  success  the  reader  must  judge.  I am  fully  aware  of  the  difficulty  of  the 
task,  and  of  my  own  incompetency  to  treat  it  as  might  be  wished ; but,  on  the  other 
hand,  I may  perhaps  plead  that  in  the  course  of  a cruise  of  some  months  along  the 
east  coast  of  Australia  and  in  Bass’s  Strait  I have  enjoyed  peculiar  opportunities  for 
investigations  of  this  kind,  and  that  the  study  of  other  families  hitherto  but  imper- 
fectly known,  has  done  much  towards  suggesting  a clue  in  unravelling  many  com- 
plexities, at  first  sight  not  very  intelligible. 

3.  From  the  time  of  Peron  and  Lesueur  downwards,  much  has  been  said  of  the 
difficulties  attending  the  examination  of  the  Medusse.  I confess  I think  that  they 
have  been  greatly  exaggerated  ; at  least,  with  a good  microscope  and  a good  light 
(with  the  ship  tolerably  steady),  I never  failed  in  procuring  all  the  information  I re- 
quired. The  great  matter  is  to  obtain  a good  successive  supply  of  specimens,  as  the 
more  delicate  oceanic  species  are  usually  unfit  for  examination  within  a few  hours 
after  they  are  taken. 

Section  I.- — Of  the  Anatomy  of  the  Medusce. 

4.  A fully-developed  Medusa  has  the  following  parts: — 1.  A disc.  2.  Tentacles 
and  vesicular  bodies  at  the  margins  of  this  disc.  3.  A stomach  and  canals  pro- 
ceeding from  it ; and  4.  Generative  organs,  either  ovaria  or  testes.  The  tentacula 

MDCCCXLIX.  3 h 


414 


MR.  T.  H.  HUXLEY  ON  THE  ANATOMY  OF  THE  MEDUSA. 


vary  in  form  and  position  in  different  species,  and  may  be  absent ; the  other  organs 
are  constantly  present  in  the  adult  animal. 

5.  Three  well-marked  modifications  of  external  structure  result  from  variations 
in  the  relative  position  of  these  organs.  There  is  either — 1st,  a simple  stomach 
suspended  from  the  centre  of  a more  or  less  bell-shaped  disc,  the  disc  being  traversed 
by  canals,  on  some  part  of  which  the  generative  organs  are  situated,  e.g.  Geryonia, 
Thaumantias ; or  2ndly,  a simple  stomach  suspended  from  the  centre  of  a disc ; but 
the  generative  organs  are  placed  in  cavities  formed  by  the  pushing  in,  as  it  were,  of 
the  stomachal  wall,  e.g.  Aui'elia,  Phacelloyhora  \ or  3rdly,  the  under  surface  of  the 
disc  is  produced  into  four  or  more  pillars  which  divide  and  subdivide,  the  ultimate 
divisions  supporting  an  immense  number  of  small  polype-like  stomachs;  small  aper- 
tures lead  from  these  into  a system  of  canals  which  run  through  the  pillars,  and 
finally  open  into  a cavity  placed  under  the  disc ; the  generative  organs  are  attached 
to  the  under  wall  of  the  cavity,  e.g.  Rhizostoma,  Cephea. 

6.  To  avoid  circumlocution  I will  make  use  of  the  following  terms  (employed  by 
Eschscholtz  for  another  purpose)  to  designate  these  three  classes,  viz.  Cryptocarp.® 
for  the  first,  Phanerocarp^  for  the  second,  and  Rhizostomtd.®  for  the  third. 

7.  In  describing  the  anatomy  of  the  Medusae  it  will  be  found  most  convenient  to 
commence  with  the  stomach,  and  trace  the  other  organs  from  it. 

Of  the  Stomach. — This  organ  varies  extremely  both  in  shape  and  in  size  in  the 
Cryptocarpse  and  Phanerocarpae.  But  whatever  its  appearance,  it  will  be  always 
found  to  be  composed  of  two  membranes,  an  inner  and  an  outer.  These  differ  but 
little  in  structure ; both  are  cellular,  but  the  inner  is  in  general  softer,  less  transparent 
and  more  richly  ciliated,  while  it  usually  contains  but  few  thread-cells.  The  outer, 
on  the  other  hand,  is  dense,  transparent,  and  either  distinctly  cellular  or  developed 
into  a muscular  membrane.  It  may  be  ciliated  or  not,  but  it  is  usually  thickly  beset 
with  thread-cells,  either  scattered  through  its  substance  or  concentrated  upon  more 
or  less  raised  papillee  developed  from  its  surface. 

8.  I would  wish  to  lay  particular  stress  upon  the  composition  of  this  and  other 
organs  of  the  Medusee  out  of  two  distinct  membranes,  as  I believe  that  it  is  one  of  the 
essential  peculiarities  of  their  structure,  and  that  a knowledge  of  the  fact  is  of  great 
importance  in  investigating  their  homologies.  I will  call  these  two  membranes  as 
such,  and  independently  of  any  modification  into  particular  organs,  “ foundation 
membranes.” 

9.  When  the  stomach  is  attached  to  the  disc,  the  outer  membrane  passes  into  the 
general  substance  of  the  disc,  while  the  inner  becomes  continuous  with  the  lining 
membrane  of  the  canals.  There  is  a larger  or  smaller  space  between  the  inner  aper- 
ture of  the  stomach  and  the  openings  of  the  canals,  with  which  both  communicate, 
and  which  I will  therefore  call  the  “common  cavity.” 

10.  In  the  Rhizostomidse  the  structure  of  the  stomachs  is  fundamentally  the 
same,  but  they  are  very  minute,  and  are  collected  upon  the  edges  and  extremities  of 


OF  THE  STOMACH — OF  THE  DISC. 


415 


the  ramuscules  of  a common  stem  ; so  that  the  Rhizostomidse,  quoad  their  digestive 
system,  have  the  same  relation  to  the  Monostome  Medusae  as  the  Sertularian  Polypes 
have  to  the  Hydrae,  or  the  Coralline  Polypes  to  the  Actiniae. 

11.  If  one  of  the  ultimate  ramuscules  be  examined,  it  will  be  found  to  consist  of 
a thick  transparent  substance,  similar  in  constitution  to  that  of  the  mass  of  the  disc, 
through  which  there  runs,  nearer  one  edge  than  the  other,  a canal  with  a distinct 
membranous  wall  ciliated  internally.  From  this  “ common  canal”  a series  of  parallel 
diverticula  are  given  off  at  regular  intervals,  and  run  to  the  edge  of  the  branch,  where 
they  terminate  by  rounded  oblique  openings.  It  is  not  always  easy  to  see  these 
apertures,  but  I have  repeatedly  satisfied  myself  of  their  presence  by  passing  a needle 
or  other  delicate  body  into  them,  figs.  28,  29. 

12.  The  difficulty  in  seeing  the  openings  arises  in  great  measure  from  the  pre- 
sence of  a membrane  which  surrounds  and  overlaps  them,  and  being  very  irritable, 
contracts  over  them  on  being  touched.  The  membrane  consists  of  two  processes, 
one  from  each  side  of  the  perforated  edge  of  the  branch,  fig.  28.  In  Rhizostoma  these 
two  processes  generally  remain  distinct,  so  that  their  bases  form  a common  channel 
into  which  all  the  apertures  open ; but  in  Cephea  they  are  frequently  united  in  front 
of  and  behind  each  aperture  so  as  to  form  a distinct  polype-like  cell,  figs.  35,  36. 

13.  Each  membranous  process  is  composed  of  two  membranes ; the  outer  of  these 
is  continuous  with  and  passes  into  the  thick  transparent  outer  substance  above  men- 
tioned (11) ; the  other  is  less  transparent,  more  richly  ciliated,  and  continuous  with 
the  lining  membrane  of  the  canals  through  the  apertures.  The  two  membranes  are 
continuous  at  the  free  edge  of  the  fold,  and  are  here  produced  into  numerous  tenta- 
cula.  The  latter  are  beset  with  great  numbers  of  thread-cells,  and  are  in  constant 
motion  while  the  part  retains  its  vitality*,  fig.  29. 

14.  Of  the  Disc. — In  the  Medusae  monostomatoe  the  outer  membrane  of  the  sto- 
mach is,  as  I have  said,  continuous  with  the  thick  transparent  mass  of  the  disc,  as  the 
inner  membrane  is  with  the  lining  membrane  of  the  canals  which  traverse  it.  The 
disc,  therefore,  is  composed  of  two  membranes  inclosing  a cavity  variously  shaped. 

15.  I have  examined  the  minute  structure  of  the  disc  in  Rhizostoma.  The  outer 
surface  of  the  transparent  mass  is  covered  with  a delicate  epithelium  composed  of 
polygonal  nucleated  cells  joined  edge  to  edge.  Among  these  there  are  many  thread- 
cells.  Beneath  this  there  is  a thick  gelatinous  mass  which  is  made  up  of  an  appa- 
rently homogeneous  substance  containing  a multitude  of  delicate  fibres  interlacing  in 
every  direction,  in  the  meshes  of  which  lie  scattered  nucleiform  bodies.  On  the  lower 

* M.  Milne-Edwards,  in  his  “ Observations  sur  la  Structure  de  la  Meduse  Marsupiale/’  describes  the 
fringe  and  its  tentacles,  but  having  altogether  overlooked  the  true  digestive  apertures,  he  ascribes  to  the  ten- 
tacles the  function  of  villi.  “ Les  fransres  aui  garnissent  les  bras  des  rhizostomes  sont  done  bien  certainement 
des  organes  d’absorption,  et  leur  structure  les  rend  en  efFet  tres  propres  a remplir  cette  function,  qui  ici  depend 
probablement  tout  entier  d’un  phenom^ne  analogue  a celui  designe  par  M.  Dutrochet  sous  le  nom  d’endos- 
mose.” 


3 H 2 


416 


MR.  T.  H.  HUXLEY  ON  THE  ANATOMY  OF  THE  MEDUSiE. 


surface  of  the  disc,  the  only  difference  appeared  to  be  that  the  epithelium  was  replaced 
by  a layer  of  parallel  muscular  fibres. 

16.  It  might  be  said  that  the  gelatinous  substance  here  described  is  a new  struc- 
ture, and  not  a mere  thickening  of  the  outer  membrane  ; but  a precisely  similar  change 
is  undergone  by  the  outer  membrane  in  the  Diphydae,  and  here  it  can  be  easily  traced, 
e.  g.  in  the  formation  of  the  bracts  and  in  the  development  of  muscular  fibre  in  the 
outer  wall  of  the  common  tube. 

17.  The  structure  of  the  inner  membrane  of  the  disc  and  its  canals  resembles  that 
of  the  corresponding  tissue  in  the  stomach,  &c.,  but  in  the  ultimate  ramifications  of 
the  canals  it  becomes  more  delicate. 

In  these  points  there  exists  no  difference  between  the  Monostome  and  Rhizostome 
Medusae. 

18.  The  three  divisions,  however,  vary  somewhat  in  the  arrangement  of  the  cavi- 
ties and  canals  of  the  disc. 

In  the  Cryptocarpae,  the  common  cavity  .may  be  either  small  {Thaumantias)  or  large 
{Oceania)-,  from  it  there  proceed  a number  of  straight  unbranching  canals  which 
open  into  a circular  canal  running  round  the  margin  of  the  disc. 

In  the  Phanerocarpae  the  general  arrangement  is  similar,  but  the  canals  frequently 
branch  {Medusa  aitrita,  Phacelloghora)  and  anastomose  in  a reticulate  manner. 

In  many  of  the  Monostome  Medusae  the  centre  of  the  under  surface  of  the  disc 
projects  into  the  “common  cavity”  as  a rounded  boss  (fig.  11a.),  and  according  to 
its  form  and  size  will  seem  to  divide  the  former  more  or  less  into  secondary  cavities. 
This  appears  to  me  to  be  the  origin  of  the  multiple  stomachs  of  Medusa  aurita  as 
described  by  Ehrenberg. 

19.  In  the  Rhizostomidae,  the  canals  of  the  branched  processes  unite  and  open  by 
four  {Rhizostoma,  CepJiea)  or  eight  {Cassiopea})  distinct  trunks  into  a wide  curiously- 
shaped  cavity,  from  whence  anastomosing  canals  are  given  off  to  all  parts  of  the  disc 
(figs.  26,  26  a.).  The  circular  vessel  exists,  but  is  not  particularly  obvious  in  conse- 
quence of  anastomosing  branches  being  given  off  beyond  it. 

20.  In  very  many  of  the  Cryptocarpae  {Caryhdoa,  Oceania  (fig.  5 a & 6.),  Puly- 
xenia)  there  is  a circular,  valvate,  muscular  membrane  developed  from  the  inner  and 
under  edge  of  the  disc.  In  the  Phanerocarpae  such  a membrane  does  not  seem  to  be 
present,  but  in  Rhizostoma  and  Cephea  it  is  evidently  replaced  by  the  inflexed  edge 
of  the  disc,  fig.  26  a. 

21.  Of  the  Marginal  Corpuscles. — In  the  Cryptocarpae  the  marginal  corpuscles 
are  sessile  upon  the  circular  vessel,  figs.  8,  9,  10.  They  are  spheroidal  vesicles,  con- 
taining a clear  fluid,  and  one  or  more  spherical  strongly-refracting  bodies  occasion- 
ally included  within  a delicate  cell.  The  marginal  vesicles  are  placed  between  the 
inner  and  outer  membranes  of  the  circular  vessel. 

In  the  Phanerocarpae  {Phacellophora)  the  marginal  corpuscle  (figs.  25, 25  a.)  is  placed 
at  the  extremity  of  a short  double-walled  tubular  pedicle  projecting  downwards  or 


OF  THE  MARGINAL  CORPUSCLES. 


417 


towards  the  ventral  surface  of  the  disc ; the  under  margins  of  the  fissure  in  which  it 
is  lodged  are  prolonged  into  two  overlapping  fringes.  The  cavity  of  the  pedicle  is 
continuous  with  that  of  a canal  which  runs  from  the  common  cavity  directly  towards 
the  corpuscle.  Its  walls  are  continuous,  the  inner  with  the  inner  wall  of  the  canal, 
the  outer  with  the  substance  of  the  disc.  The  pedicle  is  in  fact  a mere  process  of  the 
system  of  canals,  so  that  the  position  of  the  marginal  vesicle  is  relatively  to  this 
system  the  same  as  in  the  Cryptocarpse.  A similar  remark  holds  good  with  regard 
to  the  Rhizostomidee. 

22.  In  Cephea  and  Rhizostoma  the  organ  is  placed  in  a notch  between  two  lobe- 
like processes  of  the  margin  of  the  disc,  and  looks  upwards.  On  the  upper  surface  a 
semilunar  fold  extends  from  one  lobe  to  the  other  and  covers  in  the  corpuscle  ; below, 
the  edges  of  the  lobes  are  thinned  and  overlap,  figs.  33,  34. 

23.  There  are  some  peculiarities  in  Rhizostoma  which  deserve  to  be  noticed  more 
fully.  On  the  dorsal  surface,  behind  the  semilunar  fold  above  mentioned,  there  is  a 
large  heart-shaped  depression  (fig.  33)  with  its  base  towards  the  corpuscle.  Its  sur- 
face is  thrown  into  prominent  arborescent  folds,  and  is  very  richly  ciliated.  The 
deepest  part  of  the  depression  is  towards  its  base,  and  seems  to  take  the  direction  of 
the  base  of  the  pedicle  of  the  marginal  corpuscle,  which  is  just  below  it.  I could 
not  pass  a needle  from  the  depression  into  the  cavity  of  the  pedicle,  but  I have  no 
doubt  that  they  communicate,  as  on  a lateral  view  the  deepest  part  of  the  depression 
seems  to  project  into  the  cavity  of  the  pedicle.  Furthermore,  on  pressure,  the 
granules  usually  contained  in  the  cavity  of  the  pedicle  sometimes  passed  into  the 
depression. 

24.  Ehrenberg  describes  apertures  in  Medusa  aurita  by  which  the  system  of 
canals  communicates  with  the  exterior,  but  they  are  alternate  with  the  marginal 
corpuscles,  not  under  or  above  them.  In  Cephea  Wagneri,  again,  according  to  Will, 
the  canals  open  beneath  the  marginal  vesicles.  I did  not  observe  this  in  the  Cephea 
ocellata. 

25.  On  the  ventral  surface  a much  slighter  semilunar  fold  connects  the  base  of 
the  two  lobes,  fig.  34.  In  the  centre,  behind  this,  there  is  an  elevation  of  the  sub- 
stance of  the  disc,  to  which  the  muscular  bands  which  run  along  the  under  surface 
of  the  disc  converge. 

26.  The  canal  which  runs  to  the  marginal  vesicle  gives  oft’  branches  on  each 
side,  then  opposite  the  base  of  the  vesicle  forms  a dilatation  rather  larger  than  the 
cordate  depression ; from  this  a csecal  process  passes  off  into  each  lobe,  and  so  ter- 
minates. The  termination  of  the  canal  in  Cephea  and  Phacellophora  is  similar,  but 
in  the  latter  the  caeca  gives  off  lateral  anastomosing  branches,  fig.  25. 

27.  In  Rhizostoma  the  pedicle  is  somewhat  bent  and  enlarged  at  its  upper  half. 
The  inner  membrane  is  richly  ciliated,  and  the  cavity  which  it  incloses  usually  con- 
tains a number  of  rounded  cell-like  bodies  floating  about  in  incessant  motion.  There 
is  a considerable  space  between  the  inner  and  outer  membranes,  which  are  thick,  and 


418 


MR.  T.  H.  HUXLEY  ON  THE  ANATOMY  OF  THE  MEDUSA. 


therefore,  when  viewed  by  transmitted  light,  appear  like  four  thick  fibres.  The  vesicle 
is  about  xl^th  of  an  inch  in  diameter,  more  spherical  in  small  than  in  large  indivi- 
duals ; it  contains  a closely-packed  mass  of  strongly-refracting  granules  of  an 

inch,  more  or  less,  in  diameter.  The  outer  membrane  of  the  pedicle  can  be  traced 
over  the  vesicle,  and  the  inner  probably  passes  under  it,  separating  the  cavity  of  the 
pedicle  from  the  vesicle  : the  dense  mass  of  granules  prevents  this  from  being  actually 
seen,  but  from  analogy  with  Mesonema,  &c.,  I have  no  doubt  of  the  fact. 

28.  Ehrenberg,  in  his  description  of  the  Medusa  aurita,  says,  “ Le  p^doncule 
est  attache  a une  vesicule,  dans  lequel  on  remarque,  sous  le  microscope,  un  corps 
glanduleux,  jaunatre  lorsque  la  lumiere  le  traverse  et  blanchatre  lorsque  cette  derni^re 
est  r^flechie.  De  ce  corps  il  part  deux  branches  qui  se  dirigent  vers  le  pedoncule  du 
corps  brim  jusqu’a  son  petit  bouton  ou  tete.”  And  further  on,  “ Le  corps  bifurqu^ 
place  a la  base  du  corps  brun  parait  etre  im  ganglion  nerveux,  et  ses  deux  branches 
peuvent  etre  regardees  comme  des  nerfs  optiques.”  I must  confess  that,  judging  by 
what  I have  observed  in  Rkizostoma  and  Phacellophora,  it  appears  to  me  that  these 
so-called  nervous  branches  passing  on  each  side  of  the  pedicle  towards  its  head,  are 
nothing  more  than  the  optical  expression  of  the  thickness  of  the  two  membranes  of 
which  the  pedicle  is  composed  ; and  a very  similar  explanation  may,  I think,  be  given 
of  his  intertentacular  ganglia,  which  appear  to  be  nothing  more  than  the  optical 
expression  of  the  thickened  walls  of  the  circular  canal. 

29.  Of  the  Tentacles. — ^The  tentacles  of  the  Medusae  are  of  two  kinds: — 1,  those 
which  are  processes  of  the  outer  foundation  membrane  alone;  and  2,  those  which 
are  processes  of  both  inner  and  outer  membranes,  and  therefore  contain  a cavity  con- 
tinuous with  the  common  cavity  of  the  body.  Under  the  former  class  must  be  in- 
cluded the  knob-like  processes  on  the  convex  surface  of  many  Medusae  containing 
thread-cells;  the  papillae  on  the  generative  and  stomachal  membranes  of  Phacello- 
phora,', the  thickened  margin  of  the  stomachal  membrane  in  Oceania',  the  buccal 
tentacles  of  Mesonema ; the  tentacles  of  the  fringe  of  Rhizostoma  and  Cephea,  and 
probably  the  marginal  tentacles  of  Thaunianfias.  I will  proceed  to  describe  some  of 
these  more  in  detail. 

30.  The  papillae  scattered  over  the  generative  and  stomachal  membranes  of  Pha- 
cellophora are  spherical,  and  connected  with  the  membrane  by  a somewhat  narrower 
neck.  The  substance  of  this,  as  well  as  of  the  body  itself,  is  made  up  of  large  clear 
cells,  but  the  surface  of  the  body  is  covered  with  an  immense  number  of  round  thread- 
cells,  figs.  20,  20  a. 

In  Mesonema,  the  perpendicular  membrane,  which  depends  from  the  orifice  of  the 
central  cavity,  is  prolonged  at  its  edges  into  a great  number  of  short  tentacles.  Each 
of  these  is  composed  of  an  outer  wall,  in  which  immense  numbers  of  thread-cells  are 
imbedded,  and  a central  axis  made  up  of  large  transparent  cells.  This  cellular  axis 
extends  for  some  distance  beyond  the  base  of  the  tentacle  into  the  substance  of  the 
membrane,  fig.  7- 


OF  THE  TENTACLES. 


419 


31.  The  tentacles  of  the  fringe  of  Rhl%ostoma  and  Cephea  have  already  been  de- 
scribed, fig.  13.  The  tentacles  which  beset  the  generative  membrane  closely  resemble 
them,  and  consist  of  a single  membrane,  containing  many  small  thread-cells,  4i^th 
of  an  inch  in  diameter.  Their  cavity  is  filled  with  a homogeneous  substance,  some- 
times containing  nuclei,  similar  to  those  of  the  disc  (15.)  ; the  inner  membrane  takes 
no  part  in  their  formation,  fig.  30. 

32.  The  marginal  tentacles  of  Thaumantias  are  very  similar  (fig.  3)  to  the  buccal 
tentacles  of  Mesonerna  ; they  consist  of  an  outer  membrane,  in  which  numbers  of 
thread-cells  are  imbedded,  and  an  inner  axis  composed  of  clear  cells  arranged  end  to 
end  ; they  have  a peculiarity,  which  has  been  already  pointed  out  by  Prof.  E.  Forbes, 
in  being  placed  above  the  marginal  vesicles  instead  of  being  alternate  with  them,  as 
in  the  nearly  allied  genus  Geryonia\  and  from  this  fact,  and  from  their  totally  differ- 
ent structure,  I believe  that  they  have  a totally  different  origin.  In  Geryonia  the 
tentacles  belong  to  the  second  class — are  processes  of  the  circular  canal ; in  Thau- 
mantias they  are  simple  processes  of  the  outer  foundation  membrane,  i.  e.  of  the  sub- 
stance of  the  disc.  Perhaps  this  difference  in  structure  among  the  tentacles  may 
turn  out  to  be  a good  means  of  generic  distinction  among  other  members  of  the 
class. 

33.  As  to  the  second  class  of  tentacles.  Such  are  the  marginal  tentacles  of  3Ie- 
sonema,  of  Geryonia  (Will),  of  Oceania  and  of  Medusa  aurita  (Ehrenberg);  the 
tentacles  of  the  under  surface  of  Phacellophora,  and  the  interbrachial  tentacles  of 
Cephea. 

34.  In  the  specimens  of  Mesonerna  I obtained,  there  were  not  more  than  eight 
tentacles,  placed  at  equal  distances  round  the  disc,  which  had  attained  their  full 
development.  The  interval  between  every  two  was  filled  up  by  a series  of  bud-like 
rudimentary  tentacles,  and  marginal  corpuscles  alternate  with  them.  Each  tentacle, 
in  its  bud-like  rudimentary  form,  is  simply  a csecal  process  of  the  circular  canal,  and 
has  therefore,  like  it,  a double  wall  and  an  internal  cavity,  usually  filled  with  granules 
in  rapid  motion,  produced  by  the  ciliae  of  the  inner  wall;  the  outer  wall  contains 
large  thread-cells.  The  structure  of  the  adult  tentacle  is  essentially  the  same,  but  in 
the  course  of  its  growth  it  has  become  divided  into  a lower  filamentous  portion  and 
an  upper  dilated  sac,  by  which  it  communicates  with  the  circular  canal,  fig.  8. 

The  marginal  tentacles  of  Oceania  resemble  these  in  all  points  ; they  are  double- 
walled,  communicate  freely  with  the  circular  canal,  and  contain  an  immense  number 
of  minute  thread-cells  in  their  outer  wall,  fig.  15. 

35.  In  Phacellophora  there  is  no  distinct  marginal  circular  canal,  but  the  sixteen 
radiating  canals  are  very  wide  and  sacciform,  and  communicate  only  by  anastomosing 
marginal  branches.  Eight  of  the  canals  are  narrower  and  run  to  the  marginal  cor- 
puscles. The  alternate  eight  are  very  much  wider,  and  their  outer,  under  surface  is 
beset  with  a curved  series  of  long  tentacles,  fig.  18.  Now  the  lower  wall  of  the 
canals  is  composed  of  the  two  “ foundation  membranes,”  and  the  tentacles  are  simply 


420 


MR.  T.  H.  HUXLEY  ON  THE  ANATOMY  OF  THE  MEDUSA. 


pi-olongations  of  these  membranes  ; they  are  therefore  do  able- walled,  and  contain  a 
cavity  continuous  with  that  of  the  canal.  At  their  upper  part  they  are  thicker  than 
below,  where  their  outer  membrane  is  developed  into  spherical  processes  containing 
multitudes  of  thread-cells  and  closely  resembling  those  on  the  generative  membrane 
(30.).  The  inner  cavity  becomes  obliterated  at  the  lower  part  of  the  tentacle, 
fig.  19. 

36.  The  large  interbrachial  tentacles  of  Cephea  are  processes  of  the  branched 

arms.  For  the  greater  part  of  their  length  they  have  the  same  structure  as  the  arms, 
i.  e.  consist  of  a dense,  thick,  transparent  outer  substance  and  an  inner  membranous 
wall  inclosing  a tubular  canal ; but  at  the  extremity  they  are  thickened,  and  the  outer 
wall  is  raised  into  a number  of  small  pyriform  processes,  x^^th  of  an  inch  in  diameter, 
thickly  covered  with  minute  spherical  thread-cells,  of  an  inch  in  diam.eter.  At 

the  same  time  the  central  canal  becomes  branched  out  into  a kind  of  plexus,  which 
occupies  the  interior  of  the  enlarged  end  of  the  tentacle,  fig.  37-  These  tentacles 
are  2 inches  or  more  in  length  and  ^^th  of  an  inch  in  thickness,  but  other  smaller 
tentacles,  fths  of  an  inch  in  length  by  -^th  of  an  inch  in  diameter,  depended  from 
the  arched  concavity  of  the  brachiferous  plate.  Their  general  structure  much  re- 
sembled that  of  the  foregoing,  except  that  the  central  canal  terminated  in  a blind 
simple  extremity,  and  that  the  pyriform  bodies  extended  rather  further  up  the  stem. 

Beside  these  there  was  a third  small  kind  of  tentacles,  which  appeared  as  small 
blue  points  among  the  stomachs.  These  were  clavate  bodies  placed  without  any  re- 
gular order  in  the  axils  between  the  stomachs,  and  containing  an  internal  cavity 
which  communicated  with  the  nearest  branch  of  the  common  canal.  A series  of  pyri- 
form processes,  exactly  resembling  in  form  those  above  described,  was  arranged  round 
their  hemispherical  extremities.  As  the  individual  I observed  was  a young  one  (the 
generative  organs  not  being  developed),  I conclude  that  these  were  young  forms  of 
the  longer  tentacles,  fig.  36. 

37.  Of  the  Generative  Organs. — It  has  been  already  noticed  with  regard  to  the 
Cryptocarpae  by  Will  (in  Geryonia,  Thaumantias,  Cytceis,  Polyxenia),  and  by  Milne- 
Edwards  (in  .SLquorea),  that  the  generative  organs  are  connected  with  some  part  of 
the  system  of  canals,  but  they  do  not  attempt  to  define  the  nature  of  this  connection. 
I shall  endeavour  to  do  this,  and  to  show  that  the  generative  organs,  both  in  these 
and  in  the  Phanerocarpse  and  Rhizostomidee,  are  always  portions  more  or  less  deve- 
loped of  the  wall  of  this  system  ; and  therefore  consist  of  the  two  “foundation  mem- 
branes,” in  or  between  which  the  generative  elements,  whether  ova  or  spermatozoa, 
are  developed. 

38.  In  Thaumantias  there  are  four  canals  radiating  from  the  centre  of  the  disc, 
at  right  angles  to  one  another,  and  terminating  in  a circular  vessel  at  the  edge  of  the 
disc.  Near  its  termination  each  has  a rounded  body  seated  upon  it.  In  most  of  the 
specimens  I examined  this  body  was  distended  with  ova,  and  its  structure  was  thereby 
obscured  ; but  in  one  instance  it  was  replaced  by  an  elongated,  somewhat  pyriform 


OF  THE  GENERATIVE  ORGANS. 


421 


body,  which  on  close  examination  was  found  to  be  simply  a dilatation  of  the  canal 
on  which  it  was  seated,  having  double  walls  continuous  with  those  of  the  canal,  only 
much-thickened,  and  a central  cavity  communicating  freely  with  that  of  the  canal. 
This  was  without  doubt  a young  generative  organ,  fig.  4. 

39.  In  Oceania  the  canals  are  very  numerous,  and  radiate  from  the  wide  central 
cavity  to  the  circular  vessel  at  the  margin  of  the  disc.  In  young  individuals  these 
canals  are  narrow  and  nearly  equal  throughout,  but  in  adults  their  inferior  wall,  for 
the  middle  three-fifths  of  their  extent,  is  greatly  enlarged  and  hangs  down  in  folds  or 
plaits,  fig.  15.  Under  the  microscope  the  wall  exhibits  an  immense  number  of  ova, 
of  all  sizes  and  stages  of  growth,  lying  in  its  substance ; and  if  the  edge  of  a fold  be 
examined,  these  are  seen  to  be  placed  between  the  inner  and  outer  membranes.  The 
inner  membrane  is  thick,  and  composed  of  projecting  cells  with  very  long  ciliee ; 
the  outer  membrane  is  dense,  thinner,  and  much  more  transparent,  figs.  16,  I/. 

40.  This  account  agrees  in  its  general  details  very  closely  with  that  given  by 
M.  Milne-Edwards  of  the  generative  organs  oi j^lquorea*  ; and  I regret  the  less  not 
having  been  able  to  obtain  male  individuals,  as  he  expressly  states  that  in  jEquorea 
the  spermatozoa  are  developed  in  the  same  position.  There  is,  however,  one  discre- 
pancy. M.  Edwards  states  that  the  generative  lamellse  “ sont  tout  a fait  distincts 
de  la  cavite  digestive  centrale.”  I think  that  on  repeating  his  examination  he  would 
find  this  not  to  be  the  case.  In  Oceania,  at  any  rate,  I could  readily  introduce  a 
needle  from  the  stomach  into  the  canals,  and  show  that  the  lamellse  were  mere  dila- 
tations of  their  wall. 

In  Polyxenia,  where  the  canals  are  very  short  and  the  central  cavity  very  large,  the 
ova  are  situated  in  the  under  wall  of  the  cavity,  according  to  Will;  but  this  author 
enters  into  no  particulars  as  to  the  structure  of  the  wall. 

41.  The  generative  organs  of  the  Phanerocarpse  have  been  much  investigated. 
The  general  result  arrived  at  appears  to  be,  that  they  are  plaited  tubular  bands  at- 
tached to  the  concave  wall  of  a depression  existing  between  the  pillars  of  attachment 
of  the  stomachal  membrane ; that  they  are  altogether  separate  from  the  central 
cavity ; that  the  spermatozoa  are  developed  in  pyriform  sacs  opening  externally,  and 
that  the  ova  lie  free  in  the  substance  of  the  ovarial  band. 

42.  The  structure  of  the  generative  organs  in  Phacellophora  is  as  follows ; — The 
voluminous  folded  and  plaited  stomachal  membrane  is  attached  by  four  thick  pillars 
to  the  under  surface  of  the  disc.  The  edges  of  the  pillars  are  connected  by  a thin 
membrane,  which  is  concave  externally  so  as  to  form  a sort  of  shallow  depression  or 
generative  cavity,  but  the  central  and  some  of  the  marginal  parts  of  this  membrane 
are  produced  into  long  plaited  processes,  which  hang  far  out  of  the  cavity,  fig.  18. 
Each  process  is  a sort  of  sac  communicating  freely  at  its  attached  extremity  with  the 
cavity  of  the  stomach,  air,  &c.  passing  readily  from  the  one  to  the  other  It  is  in  fact 

* Annales  des  Sciences  Naturelles,  t.  xvi.,  quoted  verhatim  in  Lesson's  Histoire  Naturelle  des  Zoophytes 
Acalephes. 

3 I 


MDCCCXLIX. 


422 


MR.  T.  H.  HUXLEY  ON  THE  ANATOMY  OF  THE  MEDUSA. 


a sort  of  eversion  of  the  walls  of  the  stomach,  or  more  properly,  of  the  central  cavity. 
It  consists  in  its  upper  or  attached  part  of  nothing  more  than  the  two  “ foundation 
membranes,”  and  here  they  are  smooth,  but  at  their  lower  or  free  edge  they  become 
much  plaited,  acquire  a deeper  colour,  and  exhibit  the  characteristic  generative  ele- 
ments. Short  tentacles,  similar  to  those  of  Rhizostoma  (31.),  are  scattered  over  the 
inner  surface  of  each  process,  fig.  21. 

43.  In  the  ovarium,  the  two  membranes  develope  between  them  immense  multi- 
tudes of  ova  with  a dark  granulous  yelk  and  clear  germinal  vesicle.  The  ova  are 
attached  to  the  outer  surface  of  the  inner  membrane,  the  outer  membrane  passing 
quite  freely  over  them,  fig.  24. 

44.  The  testis  is  similarly  composed  of  two  membranes  with  an  intervening  space. 
The  inner  membrane  is  produced  into  a vast  number  of  thick  pyriform  sacs,  which 
lie  between  the  two  membranes,  with  their  blind  ends  towards  the  inner  surface  of 
the  outer  membrane ; internally,  they  open  each  by  a distinct  aperture  on  the  free 
surface  of  the  inner  membrane. 

45.  The  contents  of  the  sacs  are  spermatozoa,  and  cells  in  every  stage  of  deve- 

lopment towards  spermatozoa.  These  stages  are — 1.  Spherical  cells,  xFu^th  of  an 
inch  in  diameter,  filled  with  smaller  nucleated  cells  (fig.  23  d).  2.  Cells  exactly 

resembling  these  included  cells  but  free,  and  about  5-^^th  of  an  inch  in  diameter  (&). 

3.  Similar  cells,  occasionally  united  into  masses  with  long  filiform  productions  (c). 

4.  Similar  cells  with  a short  process  in  the  opposite  direction  also ; these  swim  about 

freely  and  sometimes  move  their  tails  {d).  5.  Perfect  spermatozoa  with  elongated 

heads  (r^s-oth  of  an  inch),  rather  larger  below  than  above,  where  they  are  not  more 
^han  ^0  oopth  of  an  inch  in  diameter,  with  very  long  tails  of  immeasurable  fineness, 
extending  from  the  larger  extremity  (e).  From  the  existence  of  these  different  stages, 
I conclude  that  the  spermatozoa  are  formed  by  the  elongation  of  the  secondary  cells 
contained  in  the  large  cells  first  mentioned. 

46.  I have  not  been  fortunate  enough  to  meet  with  any  description  of  the  gene- 
rative organs  of  the  Rhizostomidse  except  that  of  these  organs  in  Cephea  by  Will  ; 
and  as  what  I have  observed  differs  somewhat  from  his  statements,  I will  describe 
those  of  Rhizostoma  mosaica  somewhat  fully. 

In  this  Acalephe,  the  eight  arms  which  bear  the  stomachs  are  inserted  into  the 
lower  angles  of  a thick  square  plate,  which  I have  thence  called  the  “ brachiferous 
plate,”  fig.  27.  From  the  upper  angles  of  this  plate  there  arise  four  pillars,  of  the 
same  structure  as  the  peduncles  of  the  arms,  and  are  inserted  into  the  under  surface 
of  the  disc  rather  external  to  the  middle  point  between  its  centre  and  margin.  The 
‘‘brachiferous  plate”  has  no  other  attachment  to  the  disc,  so  that  it  forms  the  floor  of 
an  arched  cavity,  with  four  entrances  between  the  suspending  pillars  of  the  plate. 

The  suspending  pillars  expand  at  their  attachment  to  the  disc  into  three  thickened 
ribs  or  crura,  two  of  which  are  lateral  and  external,  and  one  central  and  internal : 
these  are  united  by  a thin  membrane.  The  central  crura  meet  and  form  a cross  under 


OF  THE  GENERATIVE  ORGANS. 


423 


the  centre  of  the  disc ; the  lateral  crura  are  continuous  with  the  substance  of  the  disc 
above,  and  each  meets  with  its  fellow  external  to  the  centre  of  the  disc,  fig.  26.  The 
central  crura  are  united  with  these  and  thence  with  the  disc  by  the  thin  membrane 
only.  It  thence  follows  that  there  exists  above  the  central  crura  and  the  connecting 
membrane  a wide  crucial  cavity  ; into  this  the  canals  of  the  suspending  pillars  open, 
and  from  it  radiate  the  canals  which  are  given  off  to  the  circumference  of  the  disc  : 
the  crucial  cavity  then  is  only  a portion  of  the  great  system  of  canals. 

4/.  The  external  surface  of  the  outer  half  of  the  thin  uniting  membrane  (which  is 
composed  solely  of  the  two  “foundation  membranes”),  is  produced  into  a vast  num- 
ber of  transverse  folds  of  a grayish -green  colour  in  the  male,  but  of  a deep  orange-red 
in  the  female,  fig.  26.  These  give  rise  to  the  appearance  of  a coloured  cross  shining- 
through  when  the  disc  is  viewed  from  above.  The  inner  side  of  the  folds  is  beset 
with  a series  of  tentacles,  the  generative  tentacles  described  above  (31),  fig.  30.  In 
young  specimens,  not  more  than  3 inches  in  diameter,  the  generative  organs  were 
undeveloped ; the  outer  portion  of  the  thin  membrane  being  as  smooth  as  the  inner, 
but  the  series  of  tentacles  already  existed*. 

In  adults  the  margins  of  the  folds  contain  the  spermatozoa  in  the  male,  the  ova  in 
the  female. 

48.  In  the  ovarium  the  ova  lie  between  the  inner  and  outer  foundation  mem- 
branes, which  are  both  ciliated  on  their  free  surfaces.  The  ova  are  attached  to  the 
outer  surface  of  the  inner  membrane  by  a kind  of  pedicle,  which  expands  into  the 
thick  vitellary  (?)  membrane;  this  chorionic  coat  is  distinctly  cellular  in  middle-sized 
ova,  in  larger  ones  it  is  thicker  and  homogeneous.  If  the  inner  surface  of  the  inner 
membrane  be  examined,  a depression  will  be  seen  opposite  each  ovum  : the  yelk  of 
the  ova  is  granulous  and  of  a bright  orange  colour.  The  germinal  vesicle  is  clear 
and  thin-walled,  and  is  y^th  of  an  inch  in  diameter ; the  germinal  spot  is  a thick- 
walled  cell  3-3^0  qth  of  an  inch  in  diameter,  fig.  32. 

49.  So  far  as  the  structure  of  the  inner  and  outer  membranes  is  concerned,  the 
testis  resembles  the  ovary.  But  the  spermatozoa  are  contained  in  ovoid  or  pyriform, 
thick-walled  sacs,  about  :^th  of  an  inch  in  long  diameter  placed  between  the  two,fig.31. 
In  one  individual  the  sperm-sacs  were  more  ovoid  in  shape,  and  did  not  appear  to  have 
any  particular  attachment  to  either  membrane,  but  in  the  rest  they  were  all  connected 
with  the  inner  membrane,  and  when  its  inner  surface  was  turned  towards  the  eye,  the 

* It  appears  to  me  that  M.  Milne-Edwards  must  have  had  a young  individual  of  Rhizostoma  before  him, 
■when  he  says  (Observations  sur  la  Structure  de  la  Meduse  Marsupiale),  “ Nor  does  the  plaited  membrane,  which 
forms  a sort  of  partition  between  the  central  and  the  four  lateral  cavities,  appear  to  be  an  organ  of  reproduc- 
tion. If  we  examine  one  of  these  membranes  superficially  with  the  naked  eye,  we  see  towards  its  upper  part  a 
kind  of  woollen  fringe,  which  at  first  sight  might  be  taken  for  a series  of  glandular  sacs,  but  by  the  aid  of  the 
microscope  it  is  found  that  this  appearance  is  due  in  fact  to  a multitude  of  suckers  {su^oh's^,  having  the  greatest 
similarity  in  form  to  those  appendages  which  are  observable  in  certain  parts  of  the  body  of  different  Zoophytes, 
such  as  Vitella,  Actinia,  &c.  From  this  it  would  appear  that  these  membranes  are  much  more  fitted  for 
absorption  or  respiration,  as  is  the  opinion  of  M.  Eysenhardt,  than  for  the  formation  of  ova.” 

3 I 2 


424 


MR.  T.  H.  HUXLEY  ON  THE  ANATOMY  OF  THE  MEDUSiE.» 


openings  of  the  sacs  could  be  perceived ; the  sacs  were  filled  with  spermatozoa  with 
triangular  heads,  about  YO^^th  of  an  inch  in  diameter,  and  very  long,  fine,  delicate 
tails,  fig.  31  a.  The  course  of  their  development  appeared  to  be  as  in  Phacello- 
phor'a, 

50.  Rhizostoma  and  Phacellophora  then  agree  in  having  the  spermatozoa  deve- 
loped in  sacs  connected  with  the  inner  “foundation  membrane”  and  opening  inter- 
nally. It  would  appear  from  this  that  the  exit  for  the  spermatozoa  is  through  the 
mouth  of  the  animals,  though  this  course  in  Rhizostoma  would  certainly  be  a rather 
circuitous  one. 

51.  The  individual  of  Cephea  (C.  ocellata)  which  I examined  resembled,  with 
regard  to  the  generative  organs,  a young  Rhizostoma.  The  line  of  generative  tentacles 
was  present,  but  the  generative  organs  were  undeveloped.  According  to  Will,  the 
structure  of  the  testis  in  Cephea  Wagneri  closely  resembles  that  of  Rhizostoma.  He 
says  that  there  is  a cavity  under  the  disc  into  which  the  canals  of  the  arms  and  disc 
open ; that  the  floor  of  this  cavity  is  forined  by  a thin  membrane  covered  with  fine 
tentacular  appendages,  and  that  the  band-like  testes  are  attached  to  the  under  free 
surface  of  the  membrane ; they  consist  of  pyriform  sacs  {flaschenfonnigen  Driischen) 
closely  applied  together,  and  each  opening  independently  below.  The  spermatozoa 
are  elongated  and  cylindrical,  and  have  a very  long,  fine  appendage. 

52.  With  regard  to  the  muscular  system  of  the  Medusae,  such  observations  as  I 

have  made  lead  me  to  believe  that  the  muscular  fibres  are  always  developed  in  the 
outer  “foundation  membrane.”  In  Rhizostoma  the  muscular  fibres  of  the  under  sur- 
face of  the  disc  are  flat,  pale,  and  from  to  y^th  of  an  inch  in  diameter.  They 

run  parallel  to  one  another,  but  the  lines  of  separation  between  them  are  not  con- 
tinuous throughout,  but  thus : each  fibre  is  made  up  of  very  small  • 

and  indistinct  fibrils,  which  are  transversely  striated,  the  striation  ~ 

being  most  distinct  at  the  edge  of  the  fibres. 

53.  I have  not  observed  any  indubitable  trace  of  a nervous  system  in  the  Medusae. 

54.  Will  has  described  a blood-vascular  system,  consisting  of  a system  of  canals 
inclosing  the  water  canals  and  containing  a distinct  fluid  with  cells  floating  in  it.  I 
have  paid  particular  attention  to  this  point  in  all  my  examinations  of  the  Medusae, 
but  notwithstanding  that  I have  had  species  of  the  very  same  genera  {Cydippe,  Cephea, 
Thaumantias)  under  my  hands,  I have  never  observed  any  trace  of  it.  I am  at  a loss 
even  to  understand  what  he  means,  unless,  as  I strongly  suspect,  he  has  taken  the 
outer  foundation  membrane,  which  occasionally  is  thick  and  distinct  from  the  inner, 
especially  about  the  circular  marginal  canal,  for  the  walls  of  a distinct  vessel.  Even 
if  this  be  the  case,  what  are  the  blood-corpuscles  ? 

55.  The  thread-cells  resemble  in  all  respects  those  of  the  Diphydge,  which  I have 
described  elsewhere,  consisting  of  a delicate  outer  cell  inclosing  another  thick-walled 
cell,  with  a spiral  filament  of  greater  or  less  length,  coiled  up  in  its  interior  and 
capable  of  protrusion  on  pressure. 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSAE. 


425 


Section  II. — Of  the  Affinities  of  the  Medusae. 

56.  Certain  general  conclusions  are  deducible  from  the  facts  stated  in  the  pre- 
ceding section.  It  would  appear, — 

1st.  That  a Medusa  consists  essentially  of  two  membranes  inclosing  a variously- 
shaped  cavity,  inasmuch  as  its  various  organs  are  so  composed  (7,  8,  14,  21,  22,  29, 
33,  38,  39,  &c.). 

2ndly.  That  the  generative  organs  are  external,  being  variously  developed  processes 
of  the  two  membranes  (38,  39,  42,  48,  49) ; and 

3rdly.  That  the  peculiar  organs  called  thread-cells  are  universally  present  (7,  15, 
31,  32). 

Now  in  these  particulars  the  Medusae  present  a striking  resemblance  to  certain 
other  families  of  Zoophytes.  These  are  the  Hydroid  and  Sertularian  Polypes,  the  Phy- 
sophoridae  and  Diphydae,  with  all  of  which  the  same  three  propositions  hold  good*. 

57-  But  in  order  to  demonstrate  that  a real  affinity  exists  among  different  classes 
of  animals,  it  is  not  sufficient  merely  to  point  out  that  certain  similarities  and  analo- 
gies exist  among  them  ; it  must  be  shown  that  they  are  constructed  upon  the  same 
anatomical  type,  that,  in  fact,  their  organs  are  homologous. 

Now  the  organs  of  two  animals  or  families  of  animals  are  homologous  when  their 
structure  is  identical,  or  when  the  differences  between  them  may  be  accounted  for  by 
the  simple  laws  of  growth.  When  the  organs  differ  considerably,  their  homology 
may  be  determined  in  two  ways,  either — 1,  by  tracing  back  the  course  of  develop- 
ment of  the  two  until  we  arrive  by  similar  stages  at  the  same  point ; or,  2,  by  inter- 
polating between  the  two  a series  of  forms  derived  from  other  animals  allied  to  both, 
the  difference  between  each  term  of  the  series  being  such  only  as  can  be  accounted 
for  by  the  laws  of  growth.  The  latter  method  is  that  which  has  been  generally  em- 
ployed under  the  name  of  Comparative  Anatomy,  the  former  being  hardly  applicable 
to  any  but  the  lower  classes  of  animals.  Both  methods  may  be  made  use  of  in  in- 
vestigating the  homologies  of  the  Medusae -f-. 

58.  A complete  identity  of  structure  connects  the  “foundation  membranes”  of 

* “ Les  parois  du  tube  nutritif  sent  formees  d’une  double  membrane  toujours  rondee  intimement  dans  cette 
partle  du  polype,  I’externe  repond  aux  teguments ; I’lnterne  est  xme  continuation  de  la  membrane  digestive  de 
la  capacite  alimentaire.” — Cuvier,  Org.  de  Generation  des  Zoophytes,  Lemons  d’Anat.  Comp.  t.  viii.  2nd  edit. 

I have  elsewhere  pointed  out  that  the  same  circumstance  obtains  among  the  Diphydse  and  Physophoridse. 

That  the  generative  organs  are  external  in  the  Sertularian  and  Hydroid  Polypes  has  been  long  known. 
Milne-Edwards  has  shown  that  they  have  a similar  position  in  one  of  the  Physophoridae  (^Apolemia) . I have 
observed  it  myself  in  the  Diphydae. 

The  presence  of  the  thread-cells  has  been  determined  by  Will  in  the  Diphydae,  by  Milne-Edwards  in  Apo- 
lemia,  by  myself  (only  ??)  in  Physalia,  Physophora,  Athorybia  and  other  Physophoridae,  and  in  the  Sertularian 
Polypes. 

f The  above  definitions  may  be  thought  needless  and  even  trite,  but  the  establishment  of  affinities  among 
animals  has  been  so  often  a mere  exercise  tke  imagination,  that  I may  be  pardoned  for  pointing  out  the 
guiding  principles  which  I have  followed,  and  by  which  I would  wish  to  be  judged. 


426 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSA. 


the  Medusse  with  the  corresponding  organs  in  the  rest  of  the  series ; and  it  is  curious 
to  remark,  that  throughout,  the  outer  and  inner  membranes  appear  to  bear  the  same 
physiological  relation  to  one  another  as  do  the  serous  and  mucous  layers  of  the  germ  ; 
the  outer  becoming  developed  into  the  muscular  system  and  giving  rise  to  the  organs 
of  offence  and  defence ; the  inner,  on  the  other  hand,  appearing  to  be  more  closely 
subservient  to  the  purposes  of  nutrition  and  generation. 

59.  The  structure  of  the  stomach  in  the  Medusae  is  in  general  identical  with  that 
of  the  same  organ  in  the  rest  of  the  series.  The  Rhizostomidse  offer  an  apparent 
difficulty,  but  it  appears  to  me  that  the  marginal  folds  in  them  answer  to  the  stomachal 
membrane  of  the  Monostome  Medusse ; the  apertures  to  the  inner  orifice  of  their 
stomach,  and  the  common  canal  to  their  “ common  cavity.”  Just  as  in  a polygastric 
Diphyes  the  common  tube  answers  to  the  chamber  into  which  the  stomach  of  a 
monogastric  Diphyes  opens;  and  in  Cephea  JVagneri  (Will)  these  resemblances  are 
still  more  striking.  He  says  that  each  cotyledon  “ has  at  its  apex  a small  round 
opening,  tlie  mouth,  which  leads  to  an  ovate  cavity,  occupying  the  whole  interior  of 
the  cotyledon.  I consider  this  as  the  proper  digestive  or  stomaehal  cavity,  and  believe 
that  the  cotyledons  have  the  same  relation  to  the  vessels  as  the  so-called  suckers 
{Sangrohren)  of  the  Diphydse  to  the  common  tube  {Saftrohre)*." 

60.  The  disc  of  a Medusa  is  represented  by  the  natatorial  organ  among  the 
Diphydse  and  Physophoridse.  Take  for  instance  the  disc  of  Oceania  or  Cytceis.  It 
is  here  a more  or  less  bell-shaped  body,  traversed  by  radiating  canals,  lined  by  a 
distinct  membrane,  united  by  a circular  canal  at  the  margin.  In  the  centre  the  radi- 
ating canals  communicate  freely  with  the  chamber  into  which  the  stomach  opens. 
The  inner  margin  of  the  disc  is  provided  with  a delicate,  circular,  valvate  membrane. 
The  same  description  applies,  word  for  word,  to  the  natatorial  organs  of  the  Diphydse 
and  Physophoridse  ; the  only  difference  being,  that  in  the  latter  the  stomach  is 
outside  the  cavity  (fig.  47)  of  the  organ,  instead  of  being,  as  in  the  Medusse,  suspended 
from  its  centre  inside,  fig.  49.  And  even  if  the  different  texture  of  the  two  organs 
should  give  rise  to  any  doubt,  the  genus  Rosacea,  in  which  the  natatorial  organ  is 
perfectly  soft  and  gelatinous,  furnishes  the  needful  intermediate  form. 

61.  The  disc  of  the  Medusse  has  no  representative  among  the  Hydrse  and  Sertu- 
lariadse.  The  cell  of  the  Sertularian  Polype  rather  resembles  the  “bract”  of  the 
Diphydse  than  the  “natatorial  organ”  in  its  structure  and  function,  and  in  this 
manner  the  Diphydse  form  a connecting  link  between  the  Medusse  and  the  Physo- 
phoridse. 

62.  Of  the  two  kinds  of  tentacles  of  the  Medusse,  the  first  is  represented,  in  the 
Physophoridse  and  Diphydse,  by  the  thickenings,  richly  beset  with  thread-cells,  that 
frequently  occur  in  the  lip  of  the  stomach  ; in  the  Sertularian  Polypes  {Plumularia, 
Canipanularia)  by  the  tentacles  of  the  margin  of  the  mouth,  which  precisely  resemble 
the  tentacles  of  the  fringe  of  Rkizostoma,  or  the  marginal  tentacles  of  Thaumantias, 

* Horse  Tergutinse,  p.  60. 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUS.®. 


427 


in  being  composed  of  a single  membrane  covered  with  thread-cells,  and  having  a 
cellular  axis. 

63.  The  second  kind  of  tentacle  is  homologous  with  the  prehensile  organs  of  the 
Diphydae  and  Physophoridse  with  the  peculiar  clavate  processes  of  Plumularia,  and 
so  far  as  I can  judge  from  descriptions  of  their  structure,  with  the  tentacles  of 
Hydra. 

All  the  organs  here  mentioned  commence  their  development  as  bud-like  processes 
of  the  two  primary  membranes,  elongating  and  attaining  the  forms  peculiar  to  their 
perfect  state  as  they  grow  older.  The  tentacles  of  the  Medusae  are  usually  developed 
(as  in  most  Monostomatae)  from  the  circular  vessel  of  the  disc,  sometimes  {Phacello- 
phora)fvom  the  diverging  canals,  sometimes,  finally,  from  the  neck  of  the  stomach 
Lymnorea,  Javonia).  The  prehensile  organs  of  the  Physophoridae  also  have  consider- 
able variety  in  position.  In  Porpita,  Vitella,  Angela  (?),  they  are  developed  from  the 
margin  of  the  float ; in  PJiysophora  and  many  others  from  the  base  or  the  pedicle  of 
the  stomach.  The  prehensile  organs  of  the  Diphydae  are  always  developed  either 
from  the  base  or  the  pedicle  of  the  stomach.  The  peculiar  clavate  organs  of  Plumu- 
laria are  developed  from  the  common  tube  independently  of  the  stomach. 

64.  The  adult  forms  of  these  organs  have  all  the  same  structure,  being  composed 
of  two  membranes,  with  a vast  number  of  thread-cells  of  larger  or  smaller  size, 
seated  in  the  substance  of  the  outer  membrane  or  between  the  inner  and  the 
outer. 

65.  The  “clavate  organs”  of  Plumularia  deserve  especial  notice,  as  I am  not 
aware  that  they  have  been  hitherto  described,  and  as  they  exemplify  in  a very  beau- 
tiful manner  the  “ unity  of  organization”  manifest  among  these  families. 

I have  found  them  in  two  species  of  Plumularia  obtained  by  the  dredge  at  Port 
Curtis  ; they  were  of  two  kinds,  the  one  attached  to  the  cell  of  the  polype,  the  other 
to  the  pedicle  of  the  ovary,  figs.  43,  44,  45.  In  each  species  there  were  three  pro- 
cesses of  the  former  kind,  two  above  proceeding  from  near  that  edge  of  the  aperture 
which  is  towards  the  stem,  the  other  below  from  the  front  part  of  the  base  of  the  cell ; 
they  were  conical  in  the  one  species,  club-shaped  and  articulated  in  the  other,  and 
consisted  of  an  external  horny  membrane  open  at  the  apex,  and  an  internal  delicate 
membrane  inclosing  a cavity,  all  these  being  continuous  with  the  corresponding 
parts  of  the  stem.  At  the  apex  of  each,  and  capable  of  being  pressed  through  the 
aperture,  lay  a number  of  thread-cells ; with  moderate  pressure  the  threads  only  of 
these  organs  were  pressed  out. 

I found  the  second  kind  of  organ  in  the  species  with  conical  processes.  It  con- 
sisted of  a stem  proceeding  from  the  pedicle  of  the  ovary,  bearing  a series  of  conical 
bodies  having  the  same  constitution  as  those  just  described,  fig.  45.  The  perfect 
resemblance  between  these  and  the  prehensile  organs  of  the  Diphydae  cannot  be 
overlooked. 

66.  The  structure  of  the  generative  organs  is  still  more  instructive.  In  the 
Medusae  I have  endeavoured  to  show  that  there  are  always  processes  of  the  two 


428 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSAE. 


foundation  membranes,  the  generative  elements  being  developed  between  them, 
figs.  \ a,  \ \ a,  18  a,  26  a. 

67.  In  the  Diphydse  (and  as  1 have  good  reason  for  believing  in  the  Physopho- 
ridae  also)  the  generative  organ  commences  as  a simple  process  of  the  common  tube 
(fig.  39  a),  and  undergoing  great  changes  of  form  in  the  course  of  its  development 
{b,  c),  it  becomes  at  last  exactly  similar  to  an  ordinary  natatorial  organ  with  a 
sac  composed  of  twm  membranes  suspended  from  its  centre,  fig.  39.  In  external 
form  it  greatly  resembles  such  a Medusa  as  Cytceis,  and  this  resemblance  is  much 
heightened  when,  as  in  some  cases,  it  becomes  detached  and  swims  freely  about, 
fig.  41.  The  ova  or  spermatozoa,  as  the  case  may  be,  are  developed  between  the  two 
membranes  of  the  sac,  the  inner  of  which  at  any  rate  is  a continuation  of  the  inner 
membrane  of  the  common  tube,  fig.  39. 

68.  The  ovarium  of  the  Plumularia  above  mentioned  (65.),  commences  as  a 
dilatation  of  the  apex  of  its  pedicel,  which  again  is  a process  of  the  common  stem. 
It  then  becomes  lenticular  with  a horny  outer  wall,  glassy  and  transparent  externally, 
but  internally  coloured  by  pigment  masses.  Internally  it  has  an  oval  cavity  com- 
municating with  that  of  the  stem  and  lined  by  a distinct  membrane,  fig.  45.  Be- 
tween the  two  membranes  is  a thick  layer  of  ova,  more  or  less  oval  in  shape,  and 
about  ^3^th  of  an  inch  in  diameter,  with  a germinal  spot  about  -^woth  of  an  inch  in 
diameter,  seated  in  the  middle  of  a clear  space  about  twice  that  size,  which  doubtless 
represents  the  germinal  vesicle. 

69.  The  account  given  by  Lowen  of  the  generative  organs  of  Campanularia 
differs  considerably  from  the  foregoing.  After  all  however  his  ‘^female  polypes” 
may  be  nothing  more  than  ovaria  similar  to  those  of  Diphyes  or  Coryne,  but  having 
the  production  of  tentacles  from  the  margin  carried  to  a greater  extent  than  in  the 
latter.  If  this  be  a correct  explanation,  the  idea  promulgated  by  Steenstrup,  that 
there  is  an  “ alternation  of  generations”  among  the  Sertularian  Polypes,  must  be 
given  up. 

70.  In  Hydra*,  the  ova  are  developed  in  similar  processes  of  the  lower  part  of 
the  body.  But  among  the  Hydroid  Polypes  the  ovaries  of  Coryne,  Syncorine  and 
Corymorpha,  as  described  by  Sars,  Lowen  and  Steenstrup,  are  most  interesting. 
They  commence  as  tubercles  of  the  stem,  afterwards  become  bodies,  precisely  re- 
sembling the  ovaria  of  the  Diphydee,  and  finally  (fig.  42)  detaching  themselves  deve- 
lope  regular  tentacles  from  their  margin.  The  ova  are  formed  between  the  tw’o 
membranes  of  the  inner  sac'f'. 

* M.  Dujardin,  Annales  des  Sciences  Naturelles,  November  1845,  states  on  the  authority  of  Ehrenberg, 
CoRDA  and  Laurent,  that  the  ova  of  the  freshwater  Polype  are  “produits  dans  I’epaisseur  meme  du  tissu  sans 
ovarie  ni  ovule  prealable.” 

t “ The  axis  of  the  bell  is  occupied  by  a membranous  sac,  which  is  a prolongation  of  the  nutritive  canal,  and 
answers  to  the  alimentary  cavity  of  the  alimentary  Polypes.  The  ova  are  developed  in  regular  series  in  the 
interval  between  this  alimentary  capsule  and  the  parietes  of  the  outer  sac,  in  an  intermediate  membranous  sac, 
distinguished  by  its  yellowish  brown  colour.” — Cuvier,  Le9ons  d’Anat.  Comparde,  t,  viii.  Organs  de  Gene- 
ration des  Zoophytes,  p.  860.  See  also  Duvernoy,  Annales  des  Sciences  Naturelles  for  November  1845. 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSAE. 


429 


71.  What  has  now  been  advanced  will  perhaps  be  deemed  evidence  sufficient  to 
demonstrate, — 1st,  that  the  organs  of  these  various  families  are  traceable  back  to  the 
same  point  in  the  way  of  development ; or  2ndly,  when  this  cannot  be  done,  that 
they  are  connected  by  natural  gradations  with  organs  which  are  so  traceable,  in 
which  case,  according  to  the  principles  advanced  in  57,  the  various  organs  are 
homologous,  and  the  families  have  a real  affinity  to  one  another  and  should  form  one 
group. 

72.  Perhaps  the  view  that  I have  taken  will  be  more  clear  if  I throw  it  into  a 
tabular  form,  placing  opposite  one  another  those  organs  in  the  different  families,  for 
the  homologies  of  which  there  is,  I think,  sufficient  evidence,  thus : — 


Stomachs  identical  in  Structure  throughout. 


Medusce.  Physophoridce.  Diphydcc.  Sertularidee.  Hydra. 


Disc 

Canals 

Common  cavity  

Canals  of  branches  (Rhiz.) 


Natatorial  organ Natatorial  organ. 

Canals  of  natatorial  organ... Canals  of  natatorial  organ. 

Common  tube Sacculus  and  common  tube.  Cavity  of  stem. 


Tentacles,  1 

2 

Generative  organs 

Marginal  vesicle . . 


Bract 

, A 

...Thickened  edge  of  stomach  

...Prehensile  organs  

r Generative  sac 

I Natatorial  organ  of  generative  sac, 


.Polype-cell. 

■v 

•Oval  tentacles. 

.Clavate  organs  ...Tentacles  (.^). 

.Generative  organ... Generative  organ. 
Natatorial  organs  (Coryne). 


73.  It  appears  then  that  these  five  families  are  by  no  means  so  distinct  as  has 
hitherto  been  supposed,  but  that  they  are  members  of  one  great  group,  organized 
upon  one  simple  and  uniform  plan,  and  even  in  their  most  complex  and  aberrant 
forms,  reducible  to  the  same  type.  And  I may  add,  finally,  that  on  this  theory  it  is 
by  no  means  difficult  to  account  for  the  remarkable  forms  presented  by  the  Medusae 
in  their  young  state.  The  Medusae  are  the  most  perfect,  the  most  individualized 
animals  of  the  series,  and  it  is  only  in  accordance  with  what  very  generally  obtains  in 
the  animal  kingdom  if  in  their  early  condition  they  approximate  towards  the  simplest 
forms  of  the  group  to  which  they  belong. 

74.  I have  purposely  avoided  all  mention  of  the  Beroidae  in  the  course  of  the 
present  paper,  although  they  have  many  remarkable  resemblances  to  the  animals  of 
which  it  treats ; still  such  observations  as  I have  been  enabled  to  make  upon  them 
have  led  me  to  the  belief,  that  they  do  not  so  much  form  a part  of  the  present  group 
as  a link  between  it  and  the  Anthozoic  Polypes.  But  1 hope  to  return  to  this  point 
upon  some  future  occasion. 


Sydney,  April  24th,  1848. 

Since  the  above  was  written  I have  had  an  opportunity  (by  the  kindness  of 
W.  MacLeay,  Esq.,  to  whose  advice  1 am  much  indebted)  of  reading  M.  Dujardin’s 
“ Memoires  sur  le  Developpement  des  Meduses  et  des  Polypes  Hydraires,”  contained 

3 K 


MDCCCXLIX. 


430 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSA. 


in  the  Annales  des  Sciences  Naturelles  for  November  1845.  This  author  has,  as  it 
appears  to  me,  been  misled  by  the  great  analogy  between  the  structure  of  a Medusa 
and  that  of  the  generative  organ  of  a Coryniform  Polype,  into  taking  the  detached 
organ  of  the  Polype  for  a real  Medusa.  He  does  not  hesitate  to  say  that  the  Clavi- 
form  Polypes  are  “ only  a first  stage  of  development  of  the  Acalephee.”  He  hints 
that  each  clavate  Polype  has  its  corresponding  Acalephe,  and  he  does  not  hesitate 
to  give  the  latter  distinct  names  as  independent  genera  {Sthenyo,  Cladonema). 

Here,  as  in  many  other  instances,  the  study  of  the  Diphydae  throws  light  upon  the 
matter.  The  detached  free-swimming  testis  or  ovary  of  a species  of  Sphenia  has  just 
as  much  claim  to  a distinct  generic  name  as  has  Sthenyo  or  Cladonema,  and  yet  in 
what  respect  does  this  differ  from  the  persistent  ovary  of  Eudoxia,  which  surely  is  an 
organ,  and  nothing  but  an  organ  ? 

Would  it  not  be  as  reasonable  to  give  a distinct  name  to  Needham’s  sperm-sacs 
because  they  exhibit  certain  independent  motions  external  to  the  body  of  the  Cepha- 
lopod  ? 

The  point  is  of  consequence,  because  it  is  anything  but  desirable  that  true  polypes 
with  medusiform  generative  organs  should  be  confounded  with  the  Polypiform  larvae 
of  true  Medusae. 


Description  of  the  Plates. 

In  all  the  sectional  diagrams  the  letters  have  the  same  meaning,  viz.  m.  Sto- 
mach. n.  Common  cavity,  o.  Canals,  p.  Generative  organ,  q.  Natatorial  organ. 
t.  Tentacle,  u.  Marginal  vesicle,  x.  Outer  membrane,  x'.  Bract,  x".  Valvular 
membrane. 

PLATE  XXXVII. 

Thaumantias ? 

Fig.  1.  Disc  seen  from  above. 

Fig.  1 a.  Imaginary  vertical  section. 

Fig.  2.  Opening  of  the  stomach  into  the  canals  seen  from  above. 

Fig.  3.  Marginal  tentacles. 

Fig.  4.  Young  generative  organ. 

Mesonema  ? 

Fig.  5.  Lateral  view  of  the  animal. 

Fig.  5 a.  Vertical  section. 

Fig.  6.  View  of  a segment  of  the  disc  ; under  surface. 
a.  Buccal  tentacles. 
h.  Canals. 

c.  Marginal  membrane  (20.). 


sr. 


MRIrcuis.  MDCCCXLIK.7’^-^,:mViU./?4^z 


Z^astrs  sc. 


4 


1 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSAE. 


431 


Fig.  7-  A single  buccal  tentacle  much  magnified. 

Fig.  8.  A portion  of  the  marginal  canal  with  a tentacle  and  two  marginal  corpuscles. 
Fig.  9.  Portion  of  the  marginal  canal  (a)  with  young  tentacle  (6),  and  a marginal 
vesicle  containing  two  corpuscles,  each  inclosed  within  a delicate  cell- wall. 
Fig.  10.  A marginal  vesicle  highly  magnified;  the  two  corpuscles  do  not  appear  to 
have  attained  their  full  development,  as  they  refract  less,  and  the  cell 
appears  more  opake. 


Oceania ? 

Fig.  11.  Lateral  view  of  the  animal. 

Fig.  11  a.  Vertical  section. 

Fig.  12.  Part  of  the  under  surface  of  the  disc. 
a.  Marginal  membrane. 
h.  Canals  and  generative  organs, 

c.  Common  cavity. 

Fig.  13.  Part  of  the  membrane  surrounding  the  mouth. 

Fig.  14.  The  edge  of  this  much  magnified. 

Fig.  15.  Part  of  the  margin  of  the  disc  much  enlarged. 
a.  Marginal  membrane. 
h.  Canal  and  generative  organs. 

c.  Tentacle. 

d.  Marginal  corpuscles. 

e.  Circular  canal. 

Fig.  16.  Portion  of  the  ovarium  so  folded  as  to  have  its  inner  membrane  («)  out- 
wards. 

Fig.  17.  Sectional  view  of  the  ovarium. 
a.  Inner  membrane. 
h.  Outer  membrane. 

c.  Ovum. 

d.  Germinal  vesicle. 

e.  Germinal  spot. 


PLATE  XXXVIII. 

Phacellophora ? 

Fig.  18.  View  of  a segment  of  the  under  surface. 
a.  Marginal  vesicles. 

h.  Tentacles  in  this  individual  very  much  shorter  than  usual. 

c.  Ovary  or  testis. 

d.  Buccal  membrane. 

Fig.  18  a.  Vertical  section. 


3 K 2 


432 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSA. 


Fig.  19.  Tentacle. 

Fig.  20.  Portion  of  the  buccal  membrane. 

Fig.  20  a.  Round  processes  containing  thread-cells  scattered  over  its  outer  surface. 
Fig.  21.  Portion  of  the  testis. 

a.  Generative  tentacles. 

Fig.  22.  Sectional  view  of  part  of  the  testis. 

a.  Outer  membrane. 

b.  Sperm-sacs. 

c.  Inner  membrane. 

Fig.  23.  Stages  of  development  of  the  spermatozoa  (45.). 

Fig.  24.  Ovarium. 

a.  Outer  membrane. 
h.  Ova. 

c.  Inner  membrane. 

Fig.  25.  Marginal  vesicle  from  the  under  surface. 
a.  Dilatation  of  the  canal. 

Fig.  25  a.  Marginal  vesicle  and  pedicle  very  much  enlarged. 

Rhizostoma  mosaica. 

Fig.  26.  View  of  the  under  surface  of  the  disc,  the  brachiferous  plate  being  cut  away 
a.  Marginal  vesicles. 

h.  Cut  extremity  of  the  suspending  pillar  of  the  brachiferous  plate. 

c.  Central  crura. 

d.  Lateral  crura. 

e.  Generative  folds. 

f.  Connecting  membrane. 

Fig.  26  a.  Vertical  section  of  the  Rhizostoma. 

Fig.  27.  Side  view  of  the  brachiferous  plate  detached. 

PLATE  XXXIX. 

Rhizostoma  mosaica. 

Fig.  28.  Extremity  of  one  of  the  ultimate  ramifications  of  the  arms. 
a.  Thick  substance  of  the  outer  membrane. 
h.  The  central  common  canal. 

c.  The  lateral  canals  leading  to  the  apertures. 

d.  The  fringes. 

Fig.  29.  Lateral  view  of  one  of  the  apertures  much  magnified. 

a.  Thick  outer  membrane. 

b.  Inner  membrane. 

c.  Lateral  canal. 

d.  Tentacles. 


J^AzZ.^hms.MDCCCXLIK. 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSA. 


433 


Fig.  30.  Portion  of  the  testis  slightly  magnified. 
a.  Generative  tentacles. 

Fig.  31.  Sectional  view  of  testis  much  magnified. 
a.  Outer  membrane. 
h.  Inner  membrane, 

c.  Sperm-sacs. 

Fig.  31  a.  Spermatozoa. 

Fig.  32.  Ovarium. 

a.  Outer  membrane. 
h.  Inner  membrane. 

c.  Ova. 

Fig.  33.  Marginal  vesicle,  upper  surface. 

a a.  Lobes  connected  by  the  arched  membrane,  h. 

c.  Caeca  of  the  canal  f. 

d.  Vesicle  on  its  pedicle. 

e.  Cordate  depression. 

Fig.  34.  Marginal  vesicle  from  below,  much  magnified. 
a a.  Lobes. 

h.  Inferior  connecting  membrane. 

c.  Caeca. 

d.  Elevation  of  the  outer  membrane. 

e.  Muscular  fibres. 


Cephea  ocellata. 

Fig.  35.  An  aperture  surrounded  by  its  membrane. 

Fig.  36.  Portion  of  the  extremity  of  an  arm,  with  a young  interbrachial  tentacle  {a). 
Fig.  37.  Extremity  of  one  of  the  large  interbrachial  tentacles. 

Diphydce. 

Fig.  38.  Vertical  section  of  a monogastric  Diphyes. 

Fig  39.  Attached  ovarium. 

a.  Natatorial  organ. 

b.  Ovisac. 

Fig.  39  «.  Youngest  stage  of  ovarium. 

a.  Simple  process  of  the  common  cavity. 
h,  c.  Ovaria  further  advanced. 

Fig.  40.  Prehensile  organ. 

a,  h.  Early  stages. 

Fig.  41.  Free-swimming  ovarium. 

a.  Natatorial  organ. 

b.  Ovisac. 


434 


MR.  T.  H.  HUXLEY  ON  THE  AFFINITIES  OF  THE  MEDUSA. 


Fig.  42.  Free-swimming  ovarium  of  Coryne  (from  Steenstrup)  to  compare  with 
fig.  41. 

Sertularidce. 

Fig.  43.  Cell  of  Plumularia ? 

a.  Peculiar  clavate  organs. 

b.  Large  thread-cells. 

Fig.  44.  Cell  of  another  Plumularia,  letters  as  before. 

Fig.  45.  Ovarium  of  fig.  43. 

a.  Organs  containing  thread-cells  similar  to  fig.  43  a. 

b.  Ova. 

Fig.  46.  Section  of  Plumularia. 

Fig.  47.  Section  of  Polygastric  Diphyes. 

Fig.  48.  Section  of  Rhizostoma. 

Fig.  49.  Section  of  Monostome  Medusa. 


[ 435  ] 


XXIII.  On  the  Microscopic  Structure  of  the  Scales  and  Dermal  Teeth  of  some 
Ganoid  and  Placoid  Fish.  By  W.  C.  Williamson,  Esq.  Communicated  hy 
Dr.  Lankester,  F.R.S. 


Received  June  1, — Read  June  21,  1849. 


A-T  an  early  period  after  the  invention  of  the  microscope,  the  structure  of  the  scales 
of  fish  attracted  the  notice  of  observers.  At  that  time,  little  was  known  respecting 
the  important  group  to  which  M.  Agassiz  has  since  applied  the  term  Ganoid ; ” 
their  attention  was  consequently  directed  to  the  other  subdivisions,  and  especially  to 
the  “ Cycloid”  forms ; the  object  aimed  at  being  to  account  for  the  concentric  circles 
on  the  surface  of  the  scale,  which  had  been  noticed  by  Barellus  in  1656*.  Hooke 
touches  upon  them  in  his  ‘ Micographia,’  published  in  1667.  Five  years  later,  the 
accurate  Leeuwenhoek  submitted  them  to  a careful  examination,  and  concluded, 
according  to  M.  Mandl,  “ Qu’il  se  forme  chaque  annee,  une  nouvelle  ecaille  au  dessous 
de  I’ancienne,  qui  la  deborde,  de  sort  que  Ton  aperqoit  sur  I’ecaille  le  bord  de  I’an- 
cienne  ecaille,  et  qu’on  peut  ainsi  en  comptant  dans  une  section  transversale  le  nombre 
des  couches,  determiner  I’^e  du  poisson  et  le  nombre  d’^cailles  accessoires,  qui  fer- 
ment I’ecaille  enti^re'l'.” 

During  a century  subsequent  to  this  discovery,  but  little  new  light  appears  to  have 
been  thrown  upon  the  subject ; and  though  Mandl,  in  the  memoir  just  quoted,  cites 
the  names  of  Reaumur,  Roberg,  Petit,  Schaffer,  Raster,  Ledermuller  and  Brou- 
soNNET,  as  having  directed  their  attention  to  it,  they  appear  to  have  left  it  pretty 
much  where  they  found  it. 

During  the  present  century,  Heusinger,  Kuntzmann,  Ehrenberg,  Agassiz,  Mandl 
and  Owen  have  in  succession  investigated  the  matter,  but  the  labours  of  the  three 
last  alone  require  a more  special  notice. 

At  an  early  period  in  the  progress  of  the  colossal  labours  of  M,  Agassiz,  he  was 
struck  with  the  vast  importance  of  studying  the  scales  of  fish,  and,  as  is  well  known, 
ultimately  made  their  variations  the  basis  of  his  classification.  In  the  fourth  chapter 
of  his  large  work,  headed  “ Dermatologie  et  en  particulier  des  Readies  des  poissons:}:,” 
he  enters  very  elaborately  into  the  structure  of  the  skin  and  scales,  with  the  relation- 
ship of  the  one  to  the  other ; and  he  especially  seeks  to  illustrate,  what  was  then  a new 
topic,  the  structure  of  the  scales  of  many  of  his  ‘^Ganoid”  fish,  pointing  out  their 
enamelled  {emailU)  surface,  the  large  development  of  a dentine-like  substance  in  the 

* Petrus.  Observationum  Microscopicarum  Centuria. 

t Annales  des  Sciences  Naturelles,  vol.  ii.  p.  338.  I Poissons  Fossiles,  vol.  i.  p.  61. 


436  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


upper  part  of  many  of  them,  as  well  as  the  existence  of  a true  osseous  tissue  with 
lacunae,  and  even  Haversian  canals  in  the  lower  portions  of  some  scales.  The  usual 
existence  of  a structure  more  or  less  laminated,  is  accurately  noticed ; and  he  espe- 
cially points  out  the  close  and  striking  resemblance  between  some  of  these  organisms 
and  the  teeth  of  fishes ; one  general  result  of  his  observations  being  a conviction 
that  these  scales  were  formed  by  the  gradual  and  successive  deposition  of  layers  of 
osseous  tissue,  a practical  revival  of  the  opinion  first  promulgated  by  Leeuwenhoek, 
nearly  two  centuries  ago.  These  views  were  opposed  by  M.  Mandl,  in  a memoir^^  in 
which  he  endeavoured  to  account  for  the  structure  of  cycloid  scales  especially  in  a 
totally  different  way.  This  publication  elicited  from  M.  Agassiz  an  effective  reply, 
in  which  he  gives  the  following  valuable  summary  of  his  views  : — “ J’envisage  I’ecaille 
du  poisson  com  me  une  secretion  epidermoidale,  absolument  analogue  a celle  des  ongles 
et  autres  de  meme  nature,  qui  s’observent  chez  les  animaux  superieures.  Cornrne  les 
ongles,  elles  se  composent  de  lamelles  tres  fines  d’une  substance  cornee,  superposees 
dans  fordre  de  leur  formation.  L’organe  secr^teur  est  la  poche  epidermoidale  dans 
laquelle  elles  sont  enfoncees  par  leurs  bords  anterieurs.  La  portion  de  fecaille  re- 
couverte  par  le  feuillet  superieur  de  cette  poche  est  plus  ou  moins  considerable  ; le 
feuillet  inferieur,  au  contraire,  recouvre  presque  toute  la  face  interne  de  fecaille,  ex- 
cept6  dans  quelques  ctenoides,  oh  la  face  inferieure  des  dentelures  est  libre.  Les 
lamelles  nouvellement  form^es,  sont  plus  modes,  mais  de  meme  composition  que  les 
plus  anciennes.  La  poche  grandit  a mesure  que  I’ecaille  develope,  de  sorte  que  les 
lames,  nouvellement  deposees,  sont  toujours  plus  grandes  que  les  anciennes.  Les 
stries  concentriques  de  la  poche  sont  dues  a cette  circonstance,  en  ce  sens  que  le 
bord  de  chaque  nouvelle  lame  occasionne  par  le  pression  qu’il  exerce  sur  la  poche 
un  pli,  ou  plutot  une  impression  tr^s  legere  qui  correspond  naturellement  au  bord  de 
cette  lame.  Les  lignes  concentriques  des  6cailles  sont  le  reflet  des  bords  des  lamelles 
superposees.  Aussi  sont  elles  plus  nombreuses  chez  les  poissons  ages  que  chez  les 
jeunes'f'.” 

In  the  body  of  his  large  work:|:,  M.  Agassiz  introduces  descriptions  of  the  micro- 
scopic structure  of  some  ganoid  scales,  especially  of  those  of  the  recent  Lepidosteus 
osseus  and  Polypterus,  as  well  as  of  the  Lepidotus  gigas  and  L.  unguiculatus : and  in 
the  volume  on  the  fossil  fish  of  the  old  red  sandstone,  he  gives  the  result  of  some  very 
careful  examinations  of  the  scales  belonging  to  many  of  the  interesting  genera  from 
that  group  of  deposits. 

Professor  Owen  has  slightly  touched  upon  the  subject  in  his  recently  published 
leetures§,  where  he  observes,  “ In  the  Lepidosteus,  the  scales  defend  the  body  in 
close-set  oblique  rows ; are  thick,  completely  ossified,  and  with  an  exterior  hard, 
shining,  enamel-like  layer,  having  the  microscopic  structure  of  the  hard  dentine  of 
sharks’  teeth  ; the  subjacent  osseous  part  exhibits  the  radiated  corpuscles.  I described 

* Annales  des  Sciences  Naturelles,  vol.  ii.  f Ibid.  vol.  xiv.  p.  108.  + Poissons  Fossiles. 

§ Lectures  on  the  Comparative  Anatomy  and  Physiology  of  the  Vertebrate  Animals,  1846,  p.  140. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  437 


the  organic  structure  of  the  so-called  ganoid  scale-bones  in  1840,  both  in  recent  and 
extinct  fishes,  showing  that  it  militated  against  the  theory  of  the  development  by 
successive  deposition  of  layers  being  applied,  at  least  to  ganoid  scales.”  A reference 
is  made  to  the  ‘ Odontography,’  p.  15,  where  I find  the  following  foot-note  ; — ‘‘A  very 
close  analogy  exists  between  the  dermal  bony  tubercles  and  spines  of  tlie  cartilagi- 
nous fishes  and  their  teeth.  The  system  of  minute  parallel  tubes,  with  their  branches 
and  anastomoses  in  the  thick  scales  of  the  extinct  Lepidotus,  is  as  complicated  as  in 
many  teeth,  and  equally  militates  against  the  theory  of  transudation  of  layers  being 
applied,  at  least  to  ganoid  scales.”  The  new  facts  brought  forward  by  Professor 
Owen  are  some  observations  on  the  opercular  and  other  bones  of  the  Carp  and  Gold- 
fish, from  which  he  concludes  that  the  opercular  bones  are  not  modified  dermal 
scales ; the  remaining  illustrations  had  already  been  developed  by  M.  Agassiz,  both 
in  his  descriptions  and  by  his  drawings*. 

The  last  writer  who  has  alluded  to  the  subject  is  Mr.  E.  Quekett.  His  observa- 
tions however-l-  are  confined  principally  to  the  forms  of  the  lacunee  found  in  the  scales 
of  Lepidosteus  osseus  and  Callichthys.  Such  was  the  state  of  this  subject  when  I 
entered  upon  a further  series  of  observations.  The  difficulty  which  I had  experienced 
in  identifying  what  I had  seen  of  the  structure  and  development  of  human  bone,  with 
the  descriptions  given  by  Muller,  Tomes,  Todd,  Bowman  and  others,  led  me  to  take 
up  the  examination  of  these  forms  of  osseous  tissue,  in  the  hope  that  they  would 
throw  some  additional  light  on  the  question.  The  wide  difference  also  which  existed 
betw'een  the  views  of  Owen  and  Agassiz  as  to  their  mode  of  growth,  rendered  a 
further  inquiry  into  the  development  of  the  scales  necessary.  I hope  and  believe  that 
the  facts  about  to  be  brought  forward  will  at  least  be  found  sufficiently  conclusive  to 
settle  the  question  ; by  showing  that,  whilst  the  scales  are  formed,  as  originally  stated 
by  M.  Agassiz,  by  the  apposition  of  successive  layers,  these  layers  are  not  generated 
by  any  process  of  secretion,  but  by  the  calcification  of  an  organized  basis,  resembling 
that  of  bones  and  teeth,  as  asserted  by  Professor  Owen, 

Though  M.  Agassiz  has  already  investigated  the  structure  of  the  scales  of  Lepi- 
dosteus osseus  and  Polypterus  niloticus\^  the  importance  of  an  accurate  knowledge  of 
these  recent  types  of  the  Sauroid  group  of  fish,  in  contributing  to  the  illustration  of 
the  fossil  species,  led  me  again  to  subject  the  scales  of  Lepidosteus  osseus  to  a careful 
examination : whilst  the  result  has  been  confirmatory  of  most  of  the  observations  of 
M.  Agassiz,  it  has  also  revealed  one  or  two  points  which  have  escaped  his  eye,  but 
which  are  of  importance. 

Plate  XL.  fig.  1 represents  a vertico-longitudinal  section  of  a scale  of  Lepidosteus 
osseus.  From  a tob  represents  the  anterior  portion  of  the  scale,  which,  when  in  situ,  is 
imbedded  in  the  skin,  and  covered  by  the  posterior  overlapping  margin  of  the  antece- 
dent scale,  c represents  the  posterior  margin.  The  whole  structure  is  composed  of 

* Poissons  Fossiles,  vol.  i.  p.  73  tab.  H. ; vol.  ii.  tab.  G. 

f Transactions  of  the  Microscopical  Society  of  London,  vol.  ii.  part  2.  J Vol.  ii.  part  2,  p.  5 et  seg. 

3 L 


MDCCCXLIX. 


438 


MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


exceedingly  thin  lamellee*,  which  are  folded  back  upon  themselves  at  the  edges  of 
the  scale,  the  lowermost  ones  overlapping  those  which'  rested  upon  them,  and  cover- 
ing them  over  to  a considerable  extent.  This  is  especially  the  case  at  the  anterior 
portion  of  the  scale,  but  also  exists  to  a considerable  extent  at  the  lateral  margins,  or 
those  which  are  parallel  to  the  mesial  line.  Fig.  2 represents  the  section  of  the  half 
of  a scale  taken  at  right  angles  to  this  line,  and  where  along  the  whole  of  the  upper 
margin  we  see  this  duplicature  of  the  lamellae  towards  the  centre  of  the  scale.  It  is 
also  seen  to  a slight  extent  along  its  anterior  border. 

Between  these  parallel  lamellae  are  multitudes  of  lacunae  with  radiating  canaliculi. 
These  lacunae  M.  Agassiz  designates  by  the  almost  exploded  term  of  “ bone-cor- 
puscles.” They  appear  to  be  cavities  between  two  contiguous  lamellae,  in  the  plane 
of  which  the  canaliculi  are  spread  out,  but  without  appearing  to  perforate  either  of 
them.  1 have  not  attempted  to  represent  them  in  the  Plate,  as  they  would  have 
rendered  its  details  confused  and  indefinite. 

Along  the  upper  margin  of  the  section,  especially  at  certain  points,  as  at  fig.  2 a, 
the  terminations  of  several  of  these  lamellae  combine  to  form  a tooth-like  projection, 
each  of  which  corresponds  with  more  clearly  marked  divisions  existing  in  the  section 
of  the  scale,  and  which  I have  distinguished  as  constituting  the  Lamince ; were  not 
these  surmounted  by  ganoin-f',  they  would  have  formed  elevated  ridges  on  the  surface 
of  the  scale. 

Arranged  nearly  at  right  angles  to  the  lamellae,  are  a number  of  narrow  tubes, 
figs.  1 y'and  2 b.  These  penetrate  from  the  exterior  to  the  interior  of  the  scale,  and 
have  usually  a diameter  of  about  g^^th  of  an  inch.  They  are  of  nearly  uniform 
width,  somewhat  undulating,  and  though  usually  simple,  sometimes  divide  into  two 
or  three  branches.  A few  of  them  terminate  in  the  inferior  and  middle  lamellae  of 
the  scale,  but  in  the  central  and  anterior  regions,  they  are  generally  prolonged  until 
reaching  within  a short  distance  from  the  upper  surface.  At  the  anterior  part,  and 
towards  the  lateral  margins,  they  terminate  in  the  region  where  the  successive  lamellae 
turn  back  upon  themselves,  figs.  1 c and  2 c.  Thus  the  scale  is  divided  into  two  por- 
tions ; a superior  one,  in  which  all  these  tubes,  preserving  their  rectangular  position  in 
relation  to  the  lamellae  through  which  they  pass,  enter  from  the  upper  surface,  and  an 
inferior  and  far  more  extensively  developed  one,  which  is  wholly  supplied  from  below. 
At  their  termination  these  tubes  generally  divide  into  two  or  three  short  branches. 
They  were  seen  by  M.  Agassiz,  but  on  some  points  our  observations  differ.  He  says 

* I have  employed  the  terms  lamellae  and  laminae  throughout  the  memoir  to  represent  two  distinct  appearances. 
The  former  I have  applied  to  the  ultimate  thin  layers  into  which  the  use  of  high  magnifying  powers  enables  us 
to  subdivide  the  thickness  of  the  scale.  By  the  latter  I have  distinguished  certain  more  conspicuous  subdivi- 
sions, each  consisting  of  numerous  lamellae,  and  each  of  which  is  thought  by  M.  Agassiz  to  be  the  result  of 
one  year’s  growth. 

t 1 have  preferred  employing  the  term  Ganoin,  to  represent  the  hyaline  substance  covering  over  many  of 
these  scales,  in  preference  to  that  of  Enamel.  It  is  different  in  its  character  from  the  prismatic  structure  covering 
the  dentine  of  the  teeth  of  mammals,  and  the  employment  of  one  term  to  designate  both  leads  to  error. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  439 


that  “ ces  tubes  vont  mourir  ala  limite  de  la  substance  osseuse,  et  jamais  on  ne  les  voit 
entrer  dans  la  couche  emaillee.”  Sometimes  however  they  do  penetrate  the  layers  of 
ganoin,  as  at  fig.  2 d,  where  the  tubes  perforate  several  of  its  laminae,  having  evidently 
once  passed  through  them  to  open  upon  the  external  surface  of  the  scale,  and  having 
only  been  closed  up  by  the  subsequent  addition  of  new  laminae  of  ganoin.  In  the  Lepi- 
dosteus  their  branching  extremity  always  terminates  in  the  structure  below  the  ganoin 
and  never  in  it. 

M.  Agassiz  thinks  that  these  tubes  have  not  served  as  channels  for  the  conveyance 
of  nutriment  to  the  interior  of  the  scale,  but  as  depots  of  calcareous  matter.  “Je 
serais  plutot  dispose  a croire  que  ces  tubes  ont  une  destination  analogue  aux  corpus- 
cules  osseux  et  des  tubes  dentaires,  savoir,  de  servir  de  depots  de  matik’e  calcaire.” 
With  this  conclusion  I cannot  agree ; the  tubes  appear  to  me  to  be  open  canals  in 
the  hard  tissue  of  the  scale.  Besides  which,  most  modern  physiologists  entertain 
a different  view,  both  of  the  lacunae  of  bone  and  the  dental  tubes  of  teeth,  to  that 
held  by  the  Swiss  philosopher. 

The  real  nature  and  use  of  these  tubes  is  a point  about  which  I am  dubious.  In 
Lepidosteus  osseus  we  only  see  their  partial  development,  but  in  some  of  the  fossil 
species,  hereafter  to  be  described,  we  shall  find  them  assuming  a new  aspect. 

In  addition  to  these,  there  exists  an  extensive  development  of  a second  set  of  tubes 
(fig.  2 e),  which  are  still  more  minute,  but  which  also  radiate  from  the  outer  surface 
to  the  inner  portions  of  the  scale.  They  penetrate  the  lamellae  in  a much  more  ob- 
lique direction,  crossing  the  larger  tubes  at  an  acute  angle,  verging  as  they  do  so,  from 
the  outer  border,  towards  the  centre  of  the  scale.  They  do  not  ascend  directly,  but 
in  the  manner  of  a succession  of  steps,  having  a constant  tendency  to  be  spread  out 
for  a short  space  between  the  lamellae,  and  then  obliquely  penetrating  those  above 
them,  they  repeat  the  same  process.  They  are  very  much  branched.  This  system 
of  tubes  appears  to  have  escaped  the  notice  of  M.  Agassiz,  and  I have  not  seen  any 
reference  to  their  existence  in  Lepidosteus  by  subsequent  writers.  We  shall  find,  as 
we  proceed,  that  in  one  form  or  another  there  are  very  few  ganoid  scales  in  which  they 
are  not  extensively  developed,  and  as  we  shall  often  have  to  refer  to  them,  I should 
propose  to  distinguish  them  by  applying  to  them  the  term  Lepidine.  Though  not  the 
homologues  of  dentine,  they  appear  to  fulfill  a similar  function  in  the  scales  to  that 
which  the  dentine  tubes  do  in  the  teeth,  though  they  are  often  limited  in  their  distri- 
bution to  particular  portions  of  the  true  scale  tissue,  which  is  not  the  case  with  dentine. 
I suspect  that  they  have  much  more  to  do  with  the  general  nutrition  of  the  scale,  than 
the  more  parallel  and  larger  tubes  previously  described  : we  shall  afterwards  find  that 
the  latter  only  exist  in  a few  groups  of  fish,  and  that  in  them  the  ultimate  distribu- 
tion of  these  tubes  is  mainly  restricted  to  particular  regions  of  the  scale.  But  the 
lepidine  tubes  are  very  different.  I have  seen  few  scales  in  which  I could  not  de- 
monstrate their  existence,  generally  crowded  together  in  vast  numbers,  and  giving- 
off  numerous  minute  branches  as  they  proceed,  to  each  succeeding  lamella,  even 

3 L 2 


440  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


when  their  distribution  is  confined,  as  we  shall  occasionally  find  it  to  be,  to  particular 
portions  of  the  scale ; they  always  penetrate  every  one  of  the  lamellse,  and  thus  com- 
municate with  each  parallel  layer  of  lacunae,  through  the  canaliculi  of  which  the 
necessary  lateral  communication  can  be  carried  on^. 

There  is  in  addition,  a third  set  of  still  larger,  though  less  numerous  canals,  which 
pass  completely  through  the  scale,  fig.  1 g.  These  are  supposed  by  M.  Agassiz  to 
convey  the  blood  through  the  scale  in  order  to  supply  the  epidermal  layer  by  which 
it  is  covered.  Existing,  as  we  shall  subsequently  see,  in  nearly  all  the  fossil  species, 
they  obviously  play  an  important  part  in  the  economy  of  the  scale,  by  keeping  up  a 
free  communication  between  its  upper  and  lower  surfaces.  They  are  not  confined  to, 
or  even  chiefly  found  in,  the  anterior  portion  of  the  scale,  which,  when  in  situ,  is  em- 
braced by  the  thick  duplicature  of  the  skin,  but  in  that  part  of  it  which  is  free,  and 
which  has  beyond  doubt  been  covered  over  with  a thin  secreting  membrane  like  a 
periosteum,  and  which  has  received  some  of  its  supply  of  blood  through  these  open 
canals,  by  means  of  anastomosing  blood-vessels,  ascending  from  the  integument 
below.  About  the  posterior  two-thirds  of  each  scale  is  covered  over  with  a layer  of 
ganoin.  In  some  parts  this  is  so  thin  as  to  be  scarcely  visible,  figs.  \h  and  2f, 
whilst  in  others  it  is  developed  into  irregular  tubercles,  fig.  2g.  From  the  latter 
representation,  we  see  the  way  in  which  these  tubercles  of  ganoin  are  formed.  They 
are,  in  fact,  prolongations  of  the  upturned  edges  of  the  bony  lamellse,  running 
towards  the  centre  of  the  scale,  but  only  covering  small  portions  of  the  surface, 
instead  of  uniformly  extending  over  the  whole,  as  we  shall  afterwards  find  to  be  the 
case  in  Lepidotus  and  other  fossil  forms.  We  see  from  this,  that  each  lamella  of  the 
ganoin  was  formed  contemporaneously  with  that  of  the  bone  from  which  it  springs; 
each  lamina,  shown  in  the  drawing,  consists  of  a number  of  more  minute  lamellse, 
as  has  been  already  observed  in  reference  to  the  osseous  portions.  With  the  excep- 
tion of  the  tubes,  of  whicli  the  orifices  have  been  already  alluded  to  as  perforating'  its 
laminse,  I have  not  been  able  to  detect  any  other  microscopic  structure  than  these 
lamellse  in  the  ganoin. 

1 subjeeted  some  of  these  scales  to  the  decalcifying  action  of  dilute  hydrochloric 
acid,  and  obtained  a dense  flexible  tissue,  preserving  all  the  original  contour  of  the 
scale.  In  this  were  still  exhibited  the  three  sets  of  canals  or  tubes,  and  the  lacunae 
with  their  canaliculi.  The  traces  of  the  lepidine  tubes  were  to  be  seen  so  crowded 
together  as  apparently  to  compose  almost  the  entire  tissue  of  the  scale.  Sections 
taken  at  right  angles  to  these  tubes  exhibited  very  similar  appearances  to  what  are 
seen  in  a corresponding  section  of  the  decalcified  tooth  of  a Cachalot,  or  any  other 

* These  tubes  appear  to  correspond  with  those  to  which  Prof.  Owen  has  applied  the  term  “plasmatic.” 
But  as  he  includes  under  this  title  all  those  commonly  known  as  canaliculi,  radiating  from  the  lacunae,  which 
are  obviously  distinct  in  their  nature,  I think  it  will  serve  the  purpose  of  rendering  our  descriptions  more  clear, 
if  we  employ  a new  term  to  distinguish  those  which  I have  designated  “lepidine”  tubes.  See  the  Lectures 
on  the  Comparative  Anatomy  and  Physiology  of  the  Vertebrate  Animals,  by  Prof.  Owen,  part  1,  p.  28.  This 
eminent  anatomist  appears  to  have  noticed  them  in  the  scale  of  the  Sturgeon. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  441 


analogous  form  of  dentine.  But  what  I more  especially  sought  for  I obtained,  in  the 
comparative  ease  with  which  vertical  sections  could  be  torn  into  fragments  along  the 
lines  of  the  original  lamellae,  in  the  same  way  that  Dr.  Sharpey  has  demonstrated  in 
the  case  of  human  bone*.  This  result  left  no  doubt  on  my  mind  as  to  the  applica- 
bility of  the  views  of  Leeuwenhoek  and  Agassiz  to  the  scales  of  Lepidosteus  osseus, 
being  thoroughly  convinced  that  their  formation  was  accomplished  by  the  successive 
organization  of  separate  lamellae,  though  this  organization  was  not  confined,  as 
imagined  by  Leeuwenhoek,  to  the  inferior  surface. 

I may  observe,  that  on  decalcification,  the  lacunae  and  tubuli  did  not  disappear,  as 
is  stated  by  M.  Agassiz,  though  they  became  somewhat  less  distinct,  as  they  do  in 
human  bone  under  similar  circumstances.  This  latter  example  has  been  already 
explained  by  Dr.  Sharpey'I';  and  his  explanation  is  probably  applicable  to  these  bony 
scales : consequently  the  circumstance  of  the  lacunae  and  tubuli  becoming  somewhat 
less  conspicuous  after  decalcification,  does  not  militate,  against  the  idea  of  their  being 
cavities. 

Did  any  doubt  exist  however  on  this  point,  the  long  streams  of  air-bubbles  which 
issue  out  of  them  on  mounting  a section  in  Canada  balsam  would  settle  the  question. 

Employing  this  scale  of  Lepidosteus  as  a valuable,  and  I believe  the  only  recent, 
type  of  its  class,  we  will  proceed  to  examine  those  of  some  of  the  numerous  fossil 
genera  which  have  been  constructed  upon  the  same  general  plan.  These  are  espe- 
cially the  widely-diffused  genera  of  Lepidntus,  Seminotus,  Dapidius,  Tetragonolepis, 
Pholidotus  and  Ptycholepis. 

Lepidotus. — The  scales  of  two  species  of  this  genus  have  already  been  examined  by 
M.  Agassiz  with  reference  to  their  microscopic  structure,  L.  unguiculatus  and  L.gigas. 
Of  the  former,  he  merely  notices  the  superimposed  arrangement  of  the  lamellee;}:.  Of 
the  latter  he  says,  “ Lorsque  I’email  est  enleve,  on  aperqoit  a la  surface  de  la  partie 
osseuse  les  bords  des  lames  d’accroissement  dont  se  composent  les  ecailles,  et  de 
distance  en  distance  des  lignes  plus  marquees,  indiquant  des  interruptions  dans  I’ac- 
croissement ; elles  sont  causees  par  I’lisure  des  bords  des  dernieres  lames  qui  ont 
precede  un  nouveau  developpement.  Je  me  suis  assure  par  I’examen  des  poissons 
vivans  que  ces  interruptions  etaient  periodiques  et  annuelles'^.” 

The  most  beautiful  scale  belonging  to  the  genus  which  has  come  under  my  notice, 
is  that  of  the  L.  semiserratus,  from  the  Whitby  lias,  two  representations  of  which  are 
given  in  figs.  3 and  4.  The  general  form  of  the  scale  is  rhomboidal,  having  one  of  its 
free  margins  furnished  with  large  teeth,  two  other  sides  of  the  rhomboid  having  been 
imbedded  in  the  soft  integument,  and  overlaid  by  the  margins  of  the  adjoining  scales. 

On  making  a vertical  section  of  the  scale  (fig.  3)  in  the  direction  of  the  lateral  line, 
we  find  it  to  consist  of  well-marked  parallel  lamime,  varying  from  -2^th  to  ^^th  of 
an  inch  in  thickness,  which,  as  in  Lepidosteus,  though  in  a less  degree,  are  turned 

* Dr.  Quain’s  Anatomy,  5th  edition,  by  Dr.  Sharpey  and  Mr.  Quain,  p.  cxlii.  t Ut  supra. 

J Poissons  Fossiles,  vol.  ii.  p.  253.  § Ibid.  vol.  ii.  part  1,  p.  237. 


442  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


upwards  at  an  acute  angle  round  the  margin  of  the  scale — especially  on  the  two  sides 
that  are  fixed  in  the  soft  integument — from  one  of  which  the  section  represented  in 
the  sketch  (fig.  3)  was  made.  These  laminse  are  composed  of  a multitude  of  still  more 
minute  lamellae.  They  are  perforated  by  a number  of  narrow  parallel  tubes  Wg^th 
of  an  inch  in  diameter,  the  greater  proportion  of  which  ascend  direct  from  the  inferior 
surface  to  the  region  immediately  under  the  ganoin,  fig.  3 a ; hut  in  the  anterior 
margin  of  the  scale  these  tubes  abandon  the  vertical  and  assume  the  horizontal  one, 
or  even  descend  obliquely  (fig.  3 h),  but  always  run  at  right  angles  to  the  plane  of  the 
laminae  through  which  they  pass.  In  the  latter  case,  instead  of  terminating,  like  the 
vertical  ones,  immediately  under  the  ganoin,  they  do  so  at  the  angles  which  the 
various  lamellae  make,  when  assuming  the  upward  direction ; many  of  them  even 
appearing  to  take  their  rise  from  the  under  surface  of  the  ganoin,  as  at  fig.  3 c;  but 
in  the  latter  case  the  tube  was  originally  in  the  position  of  fig.  3 d,  its  orifice  having 
been  subsequently  covered  over  by  the  formation  of  newer  lamellae  of  bone  and 
ganoin. 

At  the  two  free  margins  of  the  scale  which  overlap  the  concealed  borders  of  those 
behind  them,  the  tubes  ascend  from  the  lower  surface,  as  shown  at  fig.  5 h (which 
represents  a similarly  constructed  scale  of  Seminotus  rhombife?') . On  reaching  the 
ganoin  these  tubes  become  branched ; their  ramifications  spreading  out  in  a very 
thin  layer,  which  covers  the  outer  surface  of  each  of  the  ridge-like  projections  which 
form  the  upper  boundary  of  the  vertical  osseous  laminae.  This  layer  consists  of  a 
substance  alike  distinct  from  the  ganoin  above  and  the  true  bony  tissue  below,  and 
to  which  I propose  to  give  the  name  of  Kosmine  (from  Koafieiv,  to  adorn).  It  is  much 
more  dense  in  its  structure  than  the  true  bone  containing  no  lacunae  (though  these, 
as  the  case  in  the  example  before  us,  are  often  seen  through  it),  but  is  always  fur- 
nished with  some  arrangement  or  other  of  minute  branching  tubuli.  This  kosmine, 
which  has  hitherto  been  confounded  with  the  ganoin,  under  the  common  name  of 
“ enamel,”  occurs  so  frequently  as  to  constitute  an  important  feature  in  many  ganoid 
and  other  scales,  and  consequently  requires  to  be  distinguished  from  the  transparent 
and  almost  structureless  tissue  to  which  I have  limited  the  application  of  the  term 
ganoin  throughout  this  memoir. 

The  exquisitely  beautiful  appearance  produced  by  this  distribution  of  the  tubes  in 
the  scale  under  consideration,  is  shown  in  fig.  4 a,  which  represents  the  upper  surface 
of  that  portion  of  the  scale  as  seen  through  the  transparent  ganoin.  The  sharp  tooth- 
like ridges  presented  in  the  vertical  section,  fig.  3 c,  are  here  more  highly  magnified, 
and  form  parallel  spaces,  fig.  4 a,  before  reaching  which,  the  tubes  usually  divide  into 
two  or  three  branches,  which  afterwards  give  off  beautiful  arborescent  ramifications, 
reminding  us  of  leafless  trees  in  winter.  These  communicate  freely  with  one  another, 
by  means  of  anastomosing  loops,  in  the  arches  of  which  some  of  the  small  lateral 
twigs  dilate  into  crescentic  cavities,  fig.  4 h.  The  branches  of  each  tube  are  usually 
limited,  in  their  distribution,  to  the  one  lamina  to  which  it  is  destined,  but  some- 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  443 


times,  after  thus  giving  off  a group  of  branches,  the  main  trunks  pass  on  to  supply 
the  next  lamina  which  lies  on  the  inner  side. 

This  distribution  of  tubes  on  the  extremity  of  each  lamina,  shows  that  the  more 
strongly-marked  lines  of  division  which  separate  them,  in  contradistinction  to  those 
merely  dividing  the  lamellae,  are  not  due  to  “ I’usure  des  bords  des  dernieres  lames 
qui  ont  precede  un  nouveau  developpernent,”  but  to  some  internal  physiological 
cause,  which,  whatever  it  has  been,  may  have  operated  annually,  as  is  supposed  by 
M.  Agassiz. 

In  the  central  and  earliest  formed  lamellae,  these  tubes  terminate  as  at  fig.  3 b,  c 
and  d,  by  subdividing  into  two  or  three  small  branches,  but  do  not  exhibit  any  exten- 
sive ramifications.  The  same  is  also  the  case  with  the  tubes  of  the  two  opposite 
margins  which  terminate  in  the  interior  of  the  scale. 

We  also  find  in  this  scale  a development  of  lepidine  tubes;  they  are  not  dif- 
fused throughout  its  whole  extent,  as  in  Lepidosteus,  but  appear  to  be  chiefly  con- 
fined to  the  margins;  and  even  there,  only  exist  in  those  portions  of  the  lamellae 
which  assume  the  oblique  and  vertical  directions.  These  latter  are  copiously  per 
forated  by  them,  fig.  3 f,  but  the  horizontal  portions  exhibit  few,  if  any,  traces  of  tlieir 
existence. 

Between  each  of  the  contiguous  lamellae  is  distributed  a layer  of  lacunae  which 
exhibit  the  same  features  as  those  of  the  Lepidosteus  already  described.  In  the 
parallel  spaces  of  fig.  4 we  only  see  the  edges  of  the  lacunae  and  their  canaliculi 
following  the  plane  of  the  ascending  lamellae. 

On  the  upper  surface  of  the  scale  is  found  a thick  deposit  of  ganoin,  the  formation 
of  which,  the  section  represented  in  fig.  3 enables  us  to  comprehend.  At  g,  like  the 
subjacent  part  of  the  scale,  it  consists  of  parallel  laminae,  each  of  vvhich,  under  a higli 
magnifier,  is  seen  to  be  again  separated  into  still  more  minute  lamellae.  At  h,  we 
find  that  each  of  the  laminae  is  merely  a prolongation  of  a corresponding  one  in  the 
osseous  portion,  only  having  the  character  of  ganoin  instead  of  bone,  and  separated 
from  it  by  the  thin  film  of  kosmine  already  described.  To  some  extent  we  found  the 
same  condition  to  exist  in  Lepidosteus,  only  the  kosmine  was  wanting,  and  what 
was  there  seen  to  be  a partial  and  unequal  distribution,  producing  irregular  superficial 
tubercles,  here  extends  uniformly  over  the  whole  scale,  showing  that,  in  Lepidotiis  at 
least,  each  new  growth  has  completely  surrounded  all  that  had  been  previously  formed, 
enclosing  it  as  a nut  does  its  kernel  ; only  the  upper  portion  was  ganoin,  whilst  the 
lower  one  was  true  bone. 

We  also  find  in  the  large  opercular  bone  of  the  same  Lepidotus  a still  further  resem- 
blance to  the  scales  of  Lepidosteus,  m the  existence  of  similar  large  canals  communi- 
cating between  its  upper  and  lower  surfaces.  I have  observed  sections  of  these  to 
exhibit  concentric  laminae  surrounding  the  canals,  showing  that  the  membrane  which 
lined  them  was  also  a secreting  tissue,  depositing  calcareous  matter,  and  was  doubtless 
a prolongation  of  the  periosteum  already  spoken  of.  These  concentric  lamellae  do  not 


444  MR.  VF.  c.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


all  exhibit  complete  circles,  those  forming  the  canal  alone  doing  so  ; on  one  side  of,  and . 
external  to  the  latter,  we  often  observe  a number  of  half-circles,  as  if  it  had  for  a long 
time  been  merely  a groove  at  the  margin  of  the  scale.  In  other  respects,  the  bony 
lamellae  of  the  operculum  exhibit  the  same  appearances  as  those  of  the  true  scales, 
and  prove  that  it  has  been  formed  by  a similar  deposition  of  laminae.  This  close 
resemblance  between  the  minute  structure  of  the  scales  and  opercular  bones  of  Lepi- 
dotus  seems  to  support  the  view  once  entertained  by  Prof.  Owen,  but  since  abandoned 
by  him,  that  the  opercular  bone  is  merely  a modified  scale,  and  consequently  belongs 
not  to  the  endo-  but  to  the  exo-skeleton. 

Lepidotus  Mantelli  and  L.Jimhriatus  have  scales  of  a similar  structure  to  those  of 
L.  sefniserratiis,  only  the  latter  appears  to  want  the  beautiful  ramifications  of  the 
kosmine.  The  central  tubes  which  ascend  from  below  all  terminate  in  short  branches 
like  those  seen  in  the  centre  of  the  last-described  scale.  The  ganoin  of  L.  Mantelli 
is  filled  with  minute  brown  granular  points  ; but  whether  these  are  parts  of  its  original 
structure,  or  whether  it  is  merely  an  effect  of  fossilization,  I am  undecided.  I suspect 
the  former  to  be  the  case.  Similar,  but  still  more  minute,  granules  exist  in  great 
abundance  in  the  ganoin  of  L.Jimhriatus. 

Semhiotus. — Fig.  9 represents  a vertical  section  of  Seminotus  rhombijer,  taken 
parallel  to  the  mesial  line  of  the  fish.  It  exhibits  an  excellent  illustration  of  the 
general  contour  of  this  class  of  fossil  scales  : a is  the  anterior  extremity,  which  is  im- 
bedded in  the  soft  skin,  its  oblique  margin  being  overlapped  by  the  scale  in  front  of 
it : b is  the  opposite  edge,  adapted  for  resting  on  the  anterior  bevelled  portion  of  the 
adjoining  scale.  We  have  the  same  arrangement  of  laminae,  lamellae,  lacunae,  canals 
and  lepidine  tubes  as  in  Lepidotus,  only  we  want  the  arborescent  ramifications  of  the 
kosmine  tubes.  The  ganoin  exhibits  the  laminated  structure  found  in  the  other 
scales. 

Pholidotus. — In  PJioUdotus  Leachii  we  have  a close  resemblance  to  the  scale  of 
Seminotus  rhomhifer,  only  the  edges  of  the  upturned  laminae,  as  seen  in  a vertical 
section,  exhibit  less  of  a tooth-like  arrangement ; and  amongst  the  lower  laminae  of 
each  scale  is  developed  a large  central  lenticular  cavity,  produced  by  the  divergence 
of  some  of  the  last-formed  layers.  I have  not  yet  discovered  any  traces  of  an  open- 
ing into  this  cavity,  though  there  most  probably  is  one.  The  parallel  tubes  take  their 
rise  from  it  as  from  the  bases  of  ordinary  scales,  ascending  towards  the  ganoin. 

Ptycholepis  Bollensis. — In  the  structure  of  the  small  thick  scale  of  this  curious  spe- 
cies, we  find  a resemblance  to  that  of  Lepidotus  semiserratus.  The  parallel  ascending 
canals  terminate  in  a similar  thin  layer  of  kosmine,  which  exhibits  three  or  four 
parallel  rows  of  anastomosing  loops,  giving  off  minute  branching  tubuli.  The  ganoin, 
which  is  unusually  thick,  exhibits  precisely  the  same  laminated  structure  as  that  of 
the  Lepidotus. 

Beryx. — The  scales  of  a new  species  of  this  genus,  from  the  Chalk  of  Sussex,  belong 
to  the  same  group.  We  find  the  large  canals,  like  those  of  the  Lepidosteus,  commu- 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  445 


nicating  between  the  two  surfaces  of  the  scale — the  parallel  ascending  tubes,  which,  as 
in  Lepidotus  semiserratus,  teriniuate  in  a considerable  development  of  kosmine,  the 
elevated  ridges  of  which  project  into  the  ganoin.  The  anastomosing  loops  of  the 
kosmine  are  in  every  way  larger  and  stronger  than  in  any  species  hitherto  described, 
the  numerous  branches  and  twigs  which  they  give  off  from  their  elongated  arches  ex- 
hibiting the  appearance  of  cJievaux-de-frise. 

Dapidius. — In  Dapidius  orhis,  the  lamellse  of  the  scale  are  exceedingly  distinct 
and  beautifully  parallel,  but  the  division  of  them  into  laminae  is  less  obvious.  We 
have  the  large  canals  communicating  between  the  two  surfaces,  causing  the  puncta 
on  the  exterior  of  the  scale,  and  the  parallel  tubes  as  in  the  Lepidosteus.  Tlie  lepi- 
dine  tubes  are  very  extensively  developed,  especially  at  the  anterior  margin  of  the 
scale.  The  ganoin  is  remarkably  thin,  and  in  some  examples  scarcely  visible. 

In  Dapidius  grmmlosus,  the  substance  of  the  scale  has  the  same  structure  as  that 
of  D.  orhis,  but  its  surface  is  studded  over  with  scattered  raised  points,  one  of  which, 
as  seen  through  the  superficial  ganoin,  is  represented  in  fig.  5.  Each  one  forms  an 
elevated  point,  the  posterior  portion  of  which  (a)  exhibits  a defined  convex  edge.  It 
is  covered  with  a layer  of  ganoin,  which  is  but  slightly  developed  over  the  intervening 
layer  of  the  scale.  This  is  seen  in  fig.  6 a,  which  represents  a vertical  section  of  one 
of  these  tubercles,  made  in  the  direction  of  the  dotted  line,  fig.  b c c.  Under  each  of 
these  exists  a small  cavity,  figs.  5 b and  Qb,  which  opens  externally,  by  means  of 
three  or  four  small  canals,  fig.  5 d,  the  orifices  of  which  are  placed  behind  the  tubercle. 
Above  this  cavity  we  have  a development  of  kosmine,  the  tubes  of  which  chiefly  arise 
from  the  anterior  side  of  the  cavity,  6 e,  6 c.  Thus  we  find  that  each  of  these  tubercles 
consists  of  a local  development  of  kosmine  and  ganoin  upon  the  upper  laminae  of  the 
scale,  fig.  6 d,  these  latter  being  constructed  on  the  ordinary  type  seen  in  so  many  of 
the  lepidoid  scales.  To  this  limitation  in  the  distribution  of  the  kosmine  and  ganoin 
we  shall  have  to  refer  again,  as  it  constitutes  one  of  the  earliest  forms,  in  which  the 
tendency  existing  in  many  fish  to  the  development  of  dermal  teeth-like  structures, 
manifests  itself. 

Palceoniscus. — This  genus,  of  which  I have  investigated  two  species,  the  P.  comptus 
from  the  magnesian  limestone  of  Durham,  and  the  P.  Beaumonti  from  Autun,  is 
allied  in  many  respects  to  the  group  already  noticed.  In  the  arrangement  of  the 
laminse  and  lamellae,  the  scales  of  the  above  species  exhibit  the  general  aspect  of  the 
Lepidoids  already  described,  but  they  materially  differ  in  the  distribution  of  their 
system  of  internal  canals. 

On  making  a vertical  section  of  the  scale  of  P.  comptus,  parallel  with  the  mesial 
line,  we  see  none  of  the  long  parallel  tubes  traversing  the  laminae  at  right  angles, 
which  form  so  conspicuous  a feature  in  the  scales  hitherto  described.  In  other  re- 
spects, the  laminae,  fig.  7 e,  both  in  their  horizontal  and  upturned  portions,  as  well  as 
the  lacunae  and  their  canaliculi,  agree  with  those  of  Lepidotus  and  its  allies. 

On  looking  through  the  ganoin,  when  the  lower  portion  of  the  scale  has  been 

3 M 


MDCCCXLIX. 


446  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


ground  away  to  render  it  more  transparent,  we  find  a beautiful  arrangement  of 
tubes  or  canals  running  immediately  under  and  in  the  plane  of  the  ganoin,  form- 
ing, by  their  branches,  a development  of  kosmine.  The  main  channels  (7  a)  are 
slightly  undulated,  and  send  off  to  each  lamina  small  lateral  twigs  (7  b),  which, 
anastomosing  with  similar  ones  from  adjoining  tubes,  form  a series  of  loops,  the 
arborescent  terminal  ramuli  of  which  supply  the  parallel  lines  of  the  kosmine  with 
nutriment. 

The  subjacent  laminse  may  be  ground  so  thin  as  to  exhibit  no  trace  of  either 
lacunae  or  any  other  kind  of  cavity  or  perforation  whatever,  appearing  merely  as  a 
structureless  calcareous  layer  separating  two  layers  of  lacunae  and  their  parallel 
planes  of  canaliculi.  There  appears  to  be  no  way  in  which  these  horizontal  laminae 
could  receive  their  nutriment  except  through  the  lepidine  tubes.  The  latter  abound 
at  each  extremity  of  the  section,  where  the  laminae  leave  the  horizontal  to  assume  the 
upward  direction : through  the  branches  of  these  tubes  the  nutrient  fluid  might 
reach  each  layer  of  lacunae,  and,  by  means  of  their  canaliculi,  be  distributed  laterally 
to  every  portion  of  the  scale.  The  lacunae  are  somewhat  larger  than  in  Lepidotus 
semiserratus.  I have  found,  that,  however  various  may  have  been  the  dimensions  of 
the  scales  under  examination,  there  is  but  little  difference  in  the  size  of  their  lacunae. 
The  centre  of  each  scale  of  P.  Comptoni  (7  c)  merely  exhibits  a layer  of  these  lacunae, 
and  corresponding  ones,  following  the  plane  of  the  upturned  laminae,  are  seen  edge- 
ways through  the  kosmine,  7 d. 

M.  Agassiz  describes  the  enamel  {dmaiV)  of  Palceomscus  as  being  nearly  opake. 
It  is,  however,  not  more  so  than  in  any  other  genus. 

The  scale  of  P.  Beaumonti  resembles  that  of  P.  comptus  in  its  general  features,  but 
differs  in  points  of  detail.  The  large  tubes  or  canals  supplying  the  kosmine  chiefly 
enter  at  the  sides  of  the  scale,  Plate  XLI.  fig.  8 a.  They  do  not  terminate  at  the  central 
rhomboid  in  the  fine  filamentous  loops  which  characterise  P.  comptus,  but  some  of  the 
large  tubes  traverse  this  central  portion,  and  communicate  with  corresponding  ones 
entering  from  the  other  sides  of  the  scale,  8 h.  Along  the  upturned  edge  of  each  of 
the  laminee,  and  parallel  with  it,  are  large  transverse  inosculating  branches,  8 d,  which, 
by  connecting  the  main  trunks  together,  form  a network,  from  which  are  given  off  a 
vast  number  of  minute  branching  filaments ; these  are  distributed  to  the  thick  layer 
of  kosmine.  On  one  side  these  anastomosing  branches  are  very  long,  their  extent 
being  occasionally  equal  to  the  entire  diameter  of  the  scale,  8 e,  owing  to  the  entire 
absence,  in  this  portion,  of  the  large  trunks  which  enter  laterally.  The  very  few 
which  are  visible,  instead  of  being  parallel  with  the  ganoin,  seem  somewhat  to  ascend 
from  below,  8 f.  The  same  is  the  case  with  some  of  the  main  trunks  at  the  angles  of 
the  scale,  8 c. 

Its  anterior  and  posterior  margins  are  freely  supplied  with  lepidine  tubes. 

No  pencil  can  adequately  depict  the  beauty  of  the  filamentous  branches  of  the 
anastomosing  canals  in  the  kosmine  of  this  interesting  scale.  Though  differing  in 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  447 


some  of  its  details  from  that  of  P.  comptus,  the  two  evidently  belong  to  one  common 
type,  which  is  distinct  from  any  previously  described.  So  far  as  the  nutrition  of  the 
kosmine  is  concerned,  the  horizontal  canals  evidently  fulfill  the  functions  of  the  parallel 
vertical  ones  amongst  the  Lepidoti ; they  do  not  appear  to  contribute  any  branches 
to  the  osseous  lamellae,  which,  as  in  the  case  of  the  P.  comptus,  must  be  nourished 
through  the  lepidine  tubes. 

Gyrodus. — The  scale  of  a species  of  Gyrodus  from  Kellheim  exhibited  the  appear- 
ance represented  in  fig.  9*.  It  is  a modified  form  of  the  type  found  in  the  Lepi- 
dosteus,  presenting  similar  laminae,  lamellae,  parallel  tubes,  and  lepidine.  The  anterior 
portion  of  the  scale,  9*  a,  which  is  very  much  thickened,  exhibits  well-marked  con- 
centric lamellae,  which  become  curiously  inflected  towards  the  centre  of  the  scale. 
Owing  to  these  inflections,  the  posterior  portion,  which  rests  on  the  thickened  ex- 
tremity of  the  one  behind  it,  suddenly  becomes  very  thin,  fig.  9*  b,  but  still  preserving 
its  laminated  structure,  and  divisible  into  two  parts  ; a lower  one,  in  which  the  large 
tubes  ascend  from  below,  fig.  9*  c,  and  an  upper  one,  in  which  they  enter  from  above, 
fig.  9*  d.  These  tubes  are  much  less  numerous  and  less  regularly  arranged  than  in 
the  majority  of  the  preceding  scales ; those  especially  which  come  from  above  exhi- 
biting less  parallelism.  The  anterior  extremity  of  the  section,  which  when  in  situ  has 
been  deeply  imbedded  in  the  soft  integument,  is  abundantly  supplied  with  lepidine 
tubes,  fig.  9=^e;  those  from  the  upper  surface  inclining  downwards,  and  those  from 
the  lower  margin  running  upwards  in  the  direction  of  the  centre  of  the  scale. 

The  sudden  inflection  of  the  laminae  produces  the  appearance  of  the  thick  trans- 
verse rib,  extending  over  the  breadth,  which  is  the  longer  axis,  of  the  scale. 

Aspidorhynclius. — In  the  large  scale  of  Aspidorhynchus  acutirostris,  from  the  litho- 
graphic stone  of  Solenhofen,  we  find  a somewhat  analogous  structure  to  the  last, 
only  without  the  contracted  inflections  of  the  laminae.  The  bulk  of  the  scale  con- 
sists of  an  arrangement  of  lamellae,  perforated  by  beautifully  defined  and  regular 
parallel  tubes,  the  interlamellar  spaces  being  occupied  by  layers  of  magnificently 
developed  lacunae  with  their  branching  canaliculi.  These  last  are  more  beautiful 
than  in  any  species  of  fish  which  I have  examined.  The  upper  surface  of  the  scale 
exhibits  a series  of  large  and  nearly  parallel  ridges  and  furrows : a vertical  section 
(fig.  10  a)  shows  these  ridges  to  be  formed  by  an  undulatory  arrangement  of  the  up- 
turned lamellae,  which  here  take  the  place  occupied  by  tbe  ganoin  amongst  the 
Lepidoti.  These  undulating  lamellae  are  perforated  from  above  by  a series  of  tubes, 
fig.  10  6,  which,  like  those  coming  from  below,  fig.  10  c,  terminate  in  a kind  of  neu- 
tral line  between  the  upper  and  lower  portions,  which  is  about  one-third  of  the  thick- 
ness of  the  scale  below  its  upper  surface. 

If  there  is  any  ganoin  upon  the  scale,  it  is  so  thin  as  to  be  invisible.  Its  place  is 
occupied  by  these  wavy  lamellae ; and  not  only  do  the  latter  occupy  its  position,  but 
they  produce  those  superficial  irregularities,  which  in  Lepidosteus  are  due  to  the 
distribution  of  the  ganoin  : they  have  obviously  been  produced  by  the  superior  por- 

3 M 2 


448  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


tion  of  the  periosteal  membrane  corresponding  to  that  which  forms  the  ganoin  in  the 
other  scales. 

Acipemer. — Sections  of  the  scale  of  the  common  Sturgeon  present  a structure  some- 
what similar  to  that  existing  in  the  Aspidorhynchus,  only  the  numerous  ascending 
parallel  tubes  are  wholly  wanting,  and  the  process  of  involution  of  the  upper  portions 
of  the  lamellae  has  been  carried  to  a much  greater  extent,  leading  to  the  production 
of  true  Haversian  canals. 

When  one  of  the  large  lozenge-shaped  scales  is  examined,  its  upper  surface  is  found 
to  be  rough  and  thorny.  This  is  owing  to  the  existence  of  what  at  first  sight  would 
appear  to  be  a deposition  of  something  resembling  ganoin  upon  the  true  bony  tissue  : 
this  hard  substance,  which  covers  the  free  portion  of  each  scale,  has  a tendency  to  be 
arranged  in  the  form  of  radiating  ridges,  extending  from  the  centre  to  near  the  cir- 
cumference of  the  scale,  excepting  on  the  anterior  portion,  which,  having  supported  the 
opposite  margin  of  the  preceding  scale,  is  quite  smooth,  as  is  also  the  inferior  surface. 
In  the  central  portion  of  the  upper  surface  the  radii  are  less  regular  than  towards 
the  posterior  edge  of  the  scale,  being  more  cribriform  in  their  aspect,  from  the  exist- 
ence of  numerous  irregular  pits  and  deep  depressions  which  exist  in  it.  A smooth 
elevated  ridge  crosses  the  centre  parallel  with  the  lateral  line  ; this  covers  over  a very 
large  canal,  the  superficial  opening  of  which  is  in  the  smooth  anterior  portion  of  the 
scale,  which  has  been  covered  over  by  the  upper  fold  of  the  integument : its  opposite 
extremity  is  at  the  under  surface  of  the  scale,  near  its  posterior  border.  The  canal  has 
obviously  transmitted  blood-vessels,  and  probably  nervous  twigs  also,  keeping  up  a 
free  communication  between  the  two  portions  of  the  integument.  Several  smaller 
but  analogous  canals  communicate  between  the  upper  and  lower  surfaces,  each  of 
them  verging  towards  the  centre  as  it  ascends. 

The  lower  surface  is  very  smooth  and  translucent,  exhibiting  a series  of  concentric 
lines,  like  those  in  the  interior  of  a bivalve  shell,  and  which  at  first  glance  might 
lead  to  the  idea  that  the  enlargement  of  the  scale  had  been  accomplished,  as  in  the 
shell,  principally  by  the  addition  of  new  matter  to  its  edges.  Such,  however,  is  not  the 
case.  These  concentric  lines  are  in  reality  only  the  points  at  which  the  successive 
laminae  constituting  the  inferior  portion  of  the  scale  turn  upwards  and  inwards  at  a 
very  acute  angle,  as  seen  in  the  section,  fig.  11a:  these  lines  of  course  represent  what 
were  from  time  to  time  the  external  boundaries  of  the  scale,  which  were  enclosed  by 
successive  new  growths. 

As  we  have  seen  to  be  the  case  in  Aspidorhynchus,  soon  after  leaving  the  horizontal 
condition,  the  upturned  laminae  present  a strong  tendency  to  undulate,  but  even  to 
a much  greater  degree.  Near  the  margins  of  the  scale,  these  undulations  only  pro- 
duce alternating  grooves  and  ridges  on  the  surface.  This  appears  to  be  the  portion 
figured  by  M.  Agassiz*  ; whose  representation,  however,  gives  a very  imperfect  idea  of 
its  true  structure.  But  as  the  section  approaches  the  centre  of  the  scale,  we  find  that 

* Poissons  Fossiles,  vol.  ii.  Tab.  H.  fig.  22. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISK.  449 


by  the  deposition  of  new  layers,  these  grooves  are  covered  over  and  converted  into 
true  Haversian  canals.  As  we  should  expect  to  be  the  result  of  this  mode  of  growth, 
none  of  the  laminae  forming  these  canals  exhibit  complete  circles;  the  involutions 
of  the  lower  layers  are  met  by  corresponding  ones  in  the  upper  laminae ; and  by  the 
juxtaposition  of  their  respective  salient  points,  the  canal  is  rendered  complete.  Thus 
in  fig.  ] 1,  the  depressions  h are  quite  ready  to  be  covered  over  in  the  same  way  as  the 
completed  canals  c,  and  doubtless,  in  time,  the  addition  of  new  laminae  would  have 
so  closed  them  in.  The  whole  of  the  scale  is  abundantly  supplied  with  lacunae  and 
their  stellate  canaliculi,  though  in  the  inferior  horizontal  portions  of  the  lamellae 
these  are  not  so  beautifully  distinct  as  in  those  surrounding  the  Haversian  canals. 
The  latter  portions  are  also  freely  supplied  with  minute  branching  lepidine  tubes, 
which  descend  from  above,  and,  with  the  exception  of  the  large  canals  already 
described,  appear  to  be  the  only  tubes  the  scale  contains*.  This  beautiful  illustra- 
tion of  the  way  in  which  Haversian  canals  may  be  formed  is  one  of  great  value  to  the 
physiologist ; because,  from  the  size  and  distinctness  of  the  laminae,  and  the  ease 
with  which  their  direction  can  be  traced,  they  leave  no  possible  room  for  doubt  on 
the  subject.  We  thus  derive,  from  this  comparatively  remote  source,  strong  corro- 
borative evidence  of  the  accuracy  of  Professor  Sharpey’s  views  respecting  the  origin 
and  mode  of  formation  of  the  analogous  structures  in  human  bones. 

Platysomus. — Constructed  on  the  same  principle  as  those  already  noticed,  but 
exhibiting  a very  curious  modification  of  it,  is  the  scale  of  Platysomus  parvulus,  from 
the  upper  coal-measures  of  Leeds  and  Manchester. 

The  exposed  part  of  the  upper  surface  of  this  scale  is  covered  with  deep  grooves 
and  intervening  ridges,  running  nearly  parallel  with  its  long  axis,  which,  as  in  Gyro- 
dus,  really  represents  its  breadth,  and  is  at  right  angles  to  the  direction  of  the  lateral 
line  of  the  fish. 

On  making  a section  of  the  scale  in  the  opposite  direction  to  that  taken  by  these 
ridges,  we  find  it  to  consist  of  two  portions,  an  upper  and  a lower  one.  The  latter, 
figs.  12  a and  13  a,  though  apparently  of  a dense  homogeneous  structure,  exhibits,  on 
a careful  examination,  clear  evidence  that  it  consists  of  a series  of  minute  lamellae, 
though  these  do  not  appear  to  be  aggregated  into  any  more  conspicuous  laminae.  In 
the  upper  portion,  we  find  that  each  elevated  ridge  consists  of  a series  of  concentric 
arches,  fig.  12  b,  having  intervening  crescentic  spaces,  12  c,  and  exhibiting  traces  of 
the  existence  of  canals,  connecting  one  set  of  arches  with  another.  On  making  a 
section  in  the  opposite  direction,  along  the  line  of  one  of  these  elevated  ridges,  fig.  13, 
this  strueture  is  more  fully  explained  ; and  each  individual  ridge  shown  to  be  formed 
by  a series  of  arehing  plates,  13  b,  which  arise  from  the  compact  portion  of  the  scale, 
13  a,  and  after  successively  overlapping  each  other,  losing  themselves  at  the  upper 
surface  of  the  scale.  In  fig.  14,  which  represents  a horizontal  seetion,  taken  in  the 

* These  were  noticed  by  Prof.  Owen,  and  recognized  as  belonging  to  his  “ plasmatic  series.”  See  Lec- 
tures on  the  Vertebrate  Animals,  part  1,  p.  31. 


450  MR.  \V.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


plane  of  the  line  12  e,f,  the  same  letters  are  employed  to  mark  the  corresponding- 
portions  of  the  two  sections  : thus,  whilst  the  portion  14  e dips  rather  deeply  into  the 
lower  part  of  the  scale,  the  oppposite  one,  14  f,  cuts  across  the  bases  of  the  arches  14  ^ 
shortly  after  taking  their  rise  from  the  body  of  the  scale.  We  see  that  they  do  not 
spring  up  at  right  angles  to  the  axis  of  the  ridge,  but  obliquely ; the  section  of  this 
portion  of  each  intervening  cavity,  14  c,  being  somewhat  pyriform.  Each  lamina 
is  about  iwotli  inch  in  thickness.  Between  these  and  the  body  of  the  scale  is 
a series  of  anastomosing  canals,  lA  d,  which  connect  the  isolated  cavities  together, 
opening  into  them  by  small  oval  orifices,  14  h.  Traces  of  the  corresponding  canals 
are  seen  \n  \ 2 d and  13  d,  whilst  their  orifices  are  likewise  shown  in  12  h and  13  h. 

In  the  lower  part  of  this  section,  14  c,  we  find  numerous  laminse  cut  through  some- 
what obliquely,  14  g.  These  are  also  seen  in  the  two  vertical  sections. 

Singular  as  is  tlie  construction  of  this  scale,  a very  careful  investigation  of  it  has 
satisfied  me  that  it  is  formed  on  the  type  of  those  previously  described.  The  pointed 
extremity  of  the  section,  fig.  13,  represents  the  anterior  margin  of  the  scale,  which  has 
been  covered  with  the  fold  of  soft  integument  and  by  the  free  edge  of  the  antecedent 
scale  ; the  curious  arched  plates,  13  b,  are  in  reality  formed  by  the  upturned  portions 
of  the  lamellae,  and  probably  correspond  with  the  laminae  of  the  other  scales  ; each  of 
them,  whilst  enclosing  those  previously  existing,  has  not  been  deposited  in  immediate 
contact  with  it,  but  intervening  spaces  have  been  left ; whilst  between  each  of  these 
cavities  there  exist  connecting  channels  admitting  of  a free  vascular  intercommunica- 
tion. The  cavities  and  the  canals  together  appear  to  be  the  representatives  of  the  true 
Haversian  canals  ; the  large  cavities  bearing  the  same  relation  to  the  connecting 
passages,  probably,  that  the  large  cancelli  of  Mammalian  bones  do  to  the  Haversian 
canals  which  open  into  them.  Each  of  the  arched  plates  contains  numerous  lacunae, 
with  peculiarly  long  trailing  canaliculi,  especially  at  the  surface  of  the  scale.  No 
appreciable  layer  of  ganoin  covers  these  arches. 

The  modifications  of  the  Lepidostean  type  of  scale  found  in  Aspidorhynchus  wad  Aci- 
penser,  conduct  us  to  some  of  the  most  complicated  and  beautiful  structures  that  I have 
yet  seen  amongst  the  ganoid  fish,  occurring  in  the  genera  Megalichthys,  Diplopterus, 
and  Holoptychius  but  notwithstanding  all  their  complications,  it  is  not  difficult  to 
trace  the  same  principle  of  growth  which  we  have  thus  far  seen  to  apply  in  every  case. 

Megalichthys. — The  matured  scales  of  this  genus  exhibit  on  their  exposed  surfaces 
a layer  of  bright  shining  ganoin,  which  is  densely  covered  with  minute  puncta.  These 
were  noticed  by  M.  Agassiz,  who  says,  respecting  them,  “ Ce  sont  des  petits  points 
creux,  extremement  rapproches,  et  dont  les  intervalles  en  relief  forment  un  reseau  de 
mailles*.”  On  making  a vertical  section  of  a scale  of  Megalichthys  Hibbertii  from 
the  upper  coal-measures  of  Lancashire,  fig.  15, 1 found  that  each  of  these  puncta  con- 
stituted the  orifice  of  a vertical  trumpet-shaped  cavity,  15  n,  very  narrow  superiorly, 
but  expanding  and  becoming  triangular  or  quadrangular  inferiorly.  This  is  well  sliown 

* Poissons  Fossiles,  vol.  ii.  part.  2,  p.  154. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  451 


in  Plate  XLII.  fig.  16,  which  represents  a horizontal  section  of  the  upper  surface  of  the 
same  scale,  as  seen  when  looking  downward  through  the  transparent  ganoin.  The  in- 
ferior portion  has  been  more  freely  ground  away  at  the  light-coloured  extremity  h,  than 
at  the  opposite  one,  where  the  section  retains  some  of  the  deeper  osseous  layers  ; con- 
sequently these  vertical  cavities  are  here  cut  across  at  their  narrowest  part  and  exhibit 
a circular  contour,  16  a,  but  in  the  middle  portion,  we  find  that  the  section  has  passed 
through  these  cavities  lower  down,  where  they  assume  a triangular  or  quadrangular 
form,  16  5.  In  their  upper  and  middle  part,  we  not  unfrequently  see  them  to  be 
surrounded  by  concentric  rings,  reminding  us  of  the  rudimentary  Haversian  canals 
in  the  opercular  bone  of  Lepidotus  semiserratus.  After  descending  a little  distance, 
these  cavities  give  off  three,  four,  or  five  narrow  horizontal  tubes,  which  commu- 
nicate with  contiguous  cavities,  15  c;  thus  combining  to  form  a horizontal  network 
which  lies  a little  below  the  superficial  ganoin.  Neither  these  cavities  nor  the  tubes 
into  which  they  thus  subdivide  give  off  any  minute  branches.  They  are  obviously 
but  the  channels  of  communication  which  lead  to  more  important  tissues.  After 
giving  off  the  tubes,  the  cavity  becomes  suddenly  constricted,  and,  descending  a little 
further,  connects  itself  with  a second  and  more  irregular  network  of  larger  canals, 

15  and  \Q  d,  constituting  the  uppermost  of  the  Haversian  canals.  The  meshes  of 
the  network  of  tubes  15  c,  16  c,  constitute  a series  of  cup-shaped  areolar  spaces,  15  e 
and  16  e*;  into  each  of  which  the  second  layer  of  canals  sends  up  an  ascending 
branch,  or  cul-de-sac,  like  the  stump  of  a pollard  willow,  15^,  \Qf.  This  gives  off  a 
multitude  of  ramifying  tubuli,  the  main  branches  of  which  ascend,  and  distribute 
their  terminal  ramifications  immediately  under  the  ganoin.  Their  distribution  is 
very  well  seen  in  the  horizontal  section  16,  in  the  thicker  extremity  of  which  the 
branches  are  still  connected  with  the  cul-de-sac  from  which  they  spring,  IQf,  whilst 
at  the  opposite  end  we  have  only  the  branches  or  their  terminal  twigs  remaining, 

16  A,  the  cul-de-sac  being  wholly  ground  away.  The  inferior  portion  of  each  areola 
is  supplied  with  exceedingly  minute  recurved  tubuli,  which  spring  from  the  same 
point  as  the  larger  ascending  branches. 

In  each  of  these  areolar  systems,  four  or  five  of  the  branches,  instead  of  subdividing 
until  they  become  wholly  lost,  retain  their  original  calibre,  and  connect  themselves 
laterally  with  corresponding  branches  from  adjoining  areolae,  forming  a third  network 
(16g,  17  5)  which  is  still  nearer  the  ganoin  than  the  other  two,  and  which  gives  off 
numerous  minute  horizontal  and  ascending  twigs. 

After  thus  giving  rise  to  these  three  well-marked  systems  of  reticulations,  distri- 
buted in  the  plane  of  the  surface  of  the  scale,  the  trumpet-shaped  cavities  continue 
their  downward  course,  when  they  become  lost  in  an  irregular  network  of  Haversian 
canals,  15  5,  which  generally  terminate  inferiorly,  in  others  of  a much  larger  size, 

* In  the  large  scales  of  M.  Hibbertii,  each  of  these  areolae  have  an  average  diameter  of  H-g-th  of  an  inch. 
In  the  smaller  species  from  Leeds,  fig.  17,  they  average  about 


452  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


15^';  and  which  usually  exhibit  a tendency  to  run  parallel  with  the  long  axis  of  the 
scale. 

In  fig.  15  these  are  cut  transversely,  but  in  fig.  17,  which  represents  a vertical 
section  of  a smaller  species  of  MegaUckthys  from  the  coal-measures  near  Leeds,  the 
large  canal  is  divided  longitudinally,  \7  g-  In  this  latter  species,  the  ramJfications 
of  the  Haversian  canals  are  much  less  extensively  developed  than  in  M.  Hihbertii. 
The  same  is  the  case  with  an  analogous  scale  from  the  old  red  sandstone  of  Cromarty. 

With  the  exception  of  the  thin  superficial  layer  of  ganoin,  15  h,  all  that  portion  of 
the  scale  which  lies  above  the  plane  of  the  network  of  narrow  tubes,  15  c,  consists  of 
a beautiful  and  largely  developed  form  of  kosmine;  the  remaining  channels  are 
Haversian  canals,  penetrating  true  osseous  tissues.  The  two  structures  merge  in  each 
other  through  the  ascending  cul-de-sacs. 

Below  this  system  of  Haversian  canals,  we  find  a large  development  of  exceedingly 
thin  parallel  laminae,  the  majority  of  which  extend  completely  across  the  scale,  fig.  15  i 
and  18  a,  each  having  an  average  thickness  of  about  irsVolh  of  an  inch.  Their 
number  and  regular  parallelism  are  alike  the  greatest  towards  the  central  and  ante- 
rior portions  of  the  scale.  As  we  approach  the  posterior  margin,  each  one  becomes 
thicker,  less  uniformly  parallel,  and  more  disposed  to  curve  upwards,  mingling  with 
those  forming,  by  their  involutions,  the  Haversian  canals. 

Inferior  to  these  parallel  laminae,  which  divide  the  scale  horizontally  into  two  por- 
tions, we  find  a second  distribution  of  Haversian  canals,  fig.  15  A:  and  18  They 
are  especially  developed  along  the  centre  and  across  the  anterior  extremity  of  the 
scale,  where  they  form  a projecting  ridge.  I have  not  found  any  example  in  which 
these  canals  penetrate  the  parallel  laminae  towards  the  centre  of  the  structure  to  any 
considerable  extent ; but  as  we  approach  the  anterior  margin,  where  the  laminae  lose 
much  of  their  parallelism,  a free  communication  is  established  between  the  upper  and 
lower  portion  by  means  of  large  anastomosing  canals.  Along  the  inferior  surface 
the  outline  is  exceeding  irregular,  in  consequence  of  the  existence  of  the  numerous 
open  orifices  of  these  canals,  and  where,  as  at  fig.  15  /,  incipient  canals  are  in  pro- 
cess of  formation,  like  those  already  described  in  the  scale  of  the  Sturgeon.  On  the 
upper  surface  of  the  anterior  portion  of  each  scale,  also,  where  from  the  juxtaposition 
of  the  upper  fold  of  the  soft  integument  no  ganoin  was  needed,  and  consequently 
it  did  not  exist,  we  find  precisely  the  same  structure,  which  is  one  reminding  us  most 
strongly  of  the  aspect  presented  by  the  section  of  a human  foetal  bone.  Through 
these  open  canals,  blood-vessels  have  had  free  access  to  every  part  of  the  scale. 
Fig.  15  is  taken  from  near  the  lateral  portion  of  a scale,  where  the  extension  of  the 
inferior  system  of  Haversian  canals  is  limited,  but  fig.  18  is  from  a section  which 
cuts  across  the  central  ridge  already  described,  and  where  the  degree  of  their  deve- 
lopment is  well  shown.  In  this  specimen  the  ganoin  has  been  accidentally  re- 
moved. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  453 


With  the  exception  of  the  ganoin  and  kosmine,  all  the  various  modifications  of 
laminae  in  this  scale  abound  in  lacunae.  The  bony  matter  surrounding  the  Haversian 
canals  is  deposited  in  concentric  lamellae,  between  which  are  numerous  lacunae  with 
their  stellate  canaliculi  of  various  forms,  usually  of  the  common  icbthyal  type;  but 
sometimes,  especially  in  the  lamellae  nearest  to  the  canals,  showing  a disposition  to 
become  elongated  in  the  direction  parallel  to  the  axis  of  the  latter.  In  the  hori- 
zontal laminae,  already  described,  fig.  15  /,  we  find  a very  curious  form  of  lacuna. 
They  are  very  much  elongated,  being  about  inch  in  length,  and  some- 

times almost  linear,  giving  off  numerous  rectangular  canaliculi.  Not  unfrequently 
these  spring  from  the  lacuna  diagonally;  those  on  different  sides  verging  to  the 
opposite  extremities  of  the  lacuna,  as  is  seen  in  fig.  \9h,  which  sketch  represents 
the  appearance  of  these  lacunae  as  seen  under  a magnifier  of  300  diameters  linear. 
Those  of  each  layer  exhibit  a considerable  tendency  to  parallelism  of  arrangement, 
but  owing  to  the  extreme  thinness  of  the  laminae,  the  lacunae  belonging  to  two 
or  three  layers  may  be  seen  at  once,  even  under  a magnifying  power  of  300,  as 
shown  in  fig.  19:  and  it  is  a curious  fact,  that  those  constituting  one  layer  exhibit  a 
very  considerable  tendency  to  run  in  the  direction  of  the  canaliculi  of  an  adjoining 
layer.  In  fig.  19,  u,  h and  c represent  individual  lacunae  belonging  to  three  of  these 
parallel  series.  In  addition  to  the  above,  each  lacuna  gives  off  small  vertical  cana- 
liculi, which  penetrate  the  lamellae,  and  thus  connect  the  different  layers  together, 
fig.  15/.  These  structures  become  highly  interesting  when  viewed  in  connection 
with  Mr.  Quekett’s  instructive  attempts  to  identify  the  bones  of  the  four  classes  of 
the  Vertebrata  by  means  of  the  variations  of  their  microscopic  structure*.  In  that 
memoir  Mr.  Quekett  considers  that  this  elongated  form  of  lacuna  is  characteristic 
of  the  Reptilia;  and  there  is  certainly  a very  striking  resemblance  between  his  repre- 
sentation of  those  of  the  Pterodactyle-f-,  the  accuracy  of  which,  my  own  specimens  of 
the  latter  confirm,  and  my  fig.  19.  We  thus  find  that  some  of  the  elementary  tissues 
of  this  fish,  which  on  its  first  discovery  was  so  readily  mistaken  for  a reptile,  exhibit 
a most  striking  resemblance  to  the  reptilian  type:  I shall  have  to  show,  by  and  by, 
that  the  same  form  of  lacuna  exists  in  the  genera  Diplopterus  and  Holoptychius ; 
consequently  the  fusiform  lacuna  can  no  longer  be  regarded  as  typical  of  the  Reptilia, 
as  was  imagined  by  Mr.  Quekett,  though  it  is  unquestionably  the  form  most 
commonly  found  in  that  class  of  Vertebrata,  as  the  quadrate  one  is  chiefly  character- 
istic of  fish  : great  caution  however  requires  to  be  exhibited  ere  we  decide  a disputed 
question  on  this  evidence  alone.  I find  but  little  difference  between  the  majority  of 
the  lacunae  of  the  small  Platysomus parvulus,  already  described,  the  scales  of  which  are 
about  the  ^th  of  an  inch  in  length,  and  those  from  the  gigantic  femur  of  an  Iguanodon, 
in  the  possession  of  Dr.  Mantell,  which,  when  perfect,  he  informs  me  has  not  been 
less  than  27  inches  in  circumference  at  the  shaft.  A legitimate  inference  from  these 

* Transactions  of  the  Microscopical  Society  of  London,  vol.  ii.  part  2.  p.  46. 

t Tab.  8.  fig.  2,  ut  supra. 

3 N 


MDCCCXLIX. 


454  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


facts  is,  that  Mr.  Quekett’s  objection  to  the  arrangement  of  the  Lepidosiren  amongst 
fishes,  as  proposed  by  Professor  Owen,  derived  from  the  form  of  its  lacunse,  is  not  a 
valid  one. 

On  viewing  the  variety  and  complication  in  the  arrangement  of  the  elementary  tissues 
combining  to  form  the  scale  of  Megalichthys,  it  is  difiicult  to  resist  the  conclusion 
that  it  must  have  been  constructed  on  a very  different  plan  to  that  followed  in  the 
genera  previously  described.  I am  satisfied  however  that  such  has  not  been  the  case 
to  any  material  extent.  We  have  seen  that  the  results  arising  from  the  successive 
organization  of  lamellee  have  gradually  increased  in  complexity  as  we  ascended  from 
Ley'idotus  and  Seminotus  to  Gyrodus,  Platysomus,  Aspidorhynchus  and  Acipenser. 
This  complexity  appears  to  have  reached  its  climax  in  Megalichthys,  at  least  so  far 
as  refers  to  the  fish  that  I have  had  an  opportunity  of  examining.  At  the  same  time 
there  are  some  points  of  detail  which  differ  from  those  which  I have  observed  in  the 
genera  already  noticed,  and  consequently  I would  express  myself  with  legitimate 
caution  on  the  point. 

I believe,  however,  that  some  of  the  parallel  laminae,  fig.  15  / and  18  a,  have  been 
formed  the  first : whilst  additional  layers  were  being  organized,  inferiorly,  by  intra- 
membranous  ossification  through  the  agency  of  the  lower  portion  of  the  secreting 
sac,  these  laminae  being  parallel  to  their  predecessors,  the  corresponding  and  coeval 
portions,  being  secreted  by  the  upper  wall  of  the  sac,  were  much  undulated,  their  vari- 
ous inflexions  laying  the  foundation  of  the  Haversian  canals.  After  this  process  has 
continued  for  some  time,  and  a considerable  amount  of  thickness  been  given  to  the 
scale,  the  new  lamellae  added  to  its  inferior  surface,  instead  of  retaining  their  paral- 
lelism with  those  already  formed,  have  begun  to  assume  an  undulatory  arrangement, 
in  the  same  way  that  all  the  superior  ones,  corresponding  to  the  upturned  lamellae  of 
the  Sturgeon,  had  done  from  the  commencement.  This  inflexion  of  the  newly-added 
lamellae  did  not  take  place  to  an  equal  extent  over  the  entire  inferior  surface  of  the 
scale,  but  was  chiefly  confined  to  the  centre  and  to  one  extremity ; the  remaining 
portions,  and  especially  that  occupying  the  anterior  margin,  retaining  their  tendency 
to  horizontal  parallelism. 

The  osseous  framework  of  the  scale  being  thus  completed,  new  processes  have  come 
into  operation.  Prolongations  from  the  periosteal  membrane  have  lined  -the  Haver- 
sian canals,  and  these  have  deposited  new  and  internal  lamellae — at  once  thickening 
their  walls  and  diminishing  their  diameter — a process,  of  which  we  have  hitherto  met 
with  no  trace  in  the  scales  of  any  of  the  fish  described,  excepting  in  the  opercular 
bone  of  Lepidotus. 

At  some  period  prior  to  this  partial  filling  up  of  the  Haversian  canals,  a deposition 
of  kosmine  has  taken  place  on  the  surface  of  the  scale,  but  of  which,  also,  in  the  first 
instance,  only  the  framework  has  been  formed.  The  careful  preparation  and  examina- 
tion of  numerous  sections  has  enabled  me,  I trust  satisfactorily,  to  remove  much 
of  the  obscurity  that  has  hitherto  rested  upon  this  portion  of  the  subject. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  455 


Each  areola  has,  in  the  first  instance,  temporarily  presented  a similar  appearance  as 
is  permanently  exhibited  by  some  species  oi  Diplopterus  and  Holoptychius.  The  most 
superficial  portion  has  been  separated  from  the  textures  below  by  a large  horizontal 
cavity,  into  which  the  numerous  extensions  of  the  Haversian  canals  destined  to  form 
the  cul-de-sacs  have  opened.  This  superficial  chamber  has  only  been  traversed  by 
the  hollow  pillars  of  kosmine  surrounding  the  descending  trumpet-shaped  cavities. 
The  framework  of  the  kosmine  has  been  penetrated  by  a multitude  of  exceedingly 
minute  tubuli,  opening  into  the  diffused  chamber.  As  new  internal  organizations  of 
bone  have  filled  up  the  Haversian  canals,  prolongations  from  the  osseous  lamellae 
have  also  contributed  to  fill  up  this  open  space,  by  thickening  the  walls  of  the  hollow 
pillars  and  their  narrow  tubular  canals,  as  well  as  the  uppermost  layer  which  supports 
the  ganoin.  The  increase  of  these  depositions  has  led,  after  a time,  to  the  closing  up 
of  the  channels  communicating  between  contiguous  areolae,  a small  aperture  only 
being  left  permanently  open,  constituting  the  network  of  narrow  tubes,  fig.  16  g. 
The  concentric  walls  of  the  hollow  pillars,  fig.  16«,  thus  becoming  confluent,  the 
central  cavity  of  each  areola  has  been  isolated ; and  further  organizations  have  nar- 
rowed its  dimensions,  until  nothing  remained  of  each  originally  large  space  but  the 
permanent  cul-de-sac,  into  which  the  minute  tubes,  gradually  uniting  to  form  the 
larger  branches  penetrating  each  succeeding  lamella,  have  ultimately  opened. 

This  process  has  gone  on  with  the  increasing  age  of  the  fish,  until  in  some  instances 
the  cul-de-sac  is  nearly  obliterated,  leaving  only  a narrow  vertical  tube  or  stem, 
supporting  the  arborescent  arrangement  of  tubuli.  In  some  of  my  sections  these 
lamellae  are  beautifully  distinct,  the  innermost  ones  following  the  outline  of  the  cul- 
de-sac,  and  the  outer  ones  that  of  the  trumpet-shaped  cavities  around  which  they  were 
deposited.  This  arrangement  is  represented  in  the  areolae  of  fig.  15.  We  should  in- 
fer that  in  young  fish  the  cul-de-sacs  of  the  kosmine  and  the  Haversian  canals  of  the 
bone  would  be  very  large  in  proportion  to  the  solid  tissues  of  the  scale,  and  I can 
even  believe  it  possible  that  scales  of  a very  young  individual  might  easily  be  mistaken 
for  those  of  a Diplopterus.  I possess  sections  of  the  latter  which  exhibit  precisely 
this  condition.  The  Haversian  canals  appear  as  very  large  cancellated  cavities,  and 
the  structure  of  the  kosmine  also  resembles  the  early  state  Megalichthys  SiE  just 
described. 

There  appears  to  be  a period  in  the  history  of  the  scale  when  its  kosmine  ceases 
materially  to  increase  in  its  superficial  diameter.  This  extension  seems  to  have 
reached  its  limit  when  the  deep  grooves  which  mark  the  boundary  of  the  kosmine  on 
two  sides  of  the  scale  are  formed.  Further  additions  of  bony  substance  continue  to 
be  made  inferiorly,  as  well  as  to  the  upper  surface  of  the  two  margins,  which,  being 
imbedded  in  the  soft  integument,  need  neither  ganoin  nor  kosmine ; these  being  the 
portions  where  the  development  of  the  two  latter  is  arrested  by  the  groove.  Whether 
or  not  any  additions  continue  to  be  made  to  the  other  two  margins  which  overlap  the 
contiguous  scales  behind  and  beneath,  I have  not  been  able  to  satisfy  myself. 

3 N 2 


456  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


One  question  arises  to  which  I am  unable  to  give  a decisive  answer.  May  there 
not  have  been  in  this  scale  of  Megalichthys,  a central  nucleus  of  cartilage  in  the 
midst  of  the  Haversian  canals,  in  which  the  first  deposition  of  calcareous  matter  may 
have  taken  place,  and  upon  which  the  horizontal  lamellae  have  been  subsequently 
added  by  the  ordinary  process  of  intramembranous  ossification  ? This  is  just  possible, 
though  we  have  no  evidence  of  its  truth  ; whilst  the  scale  of  a Holoptychius,  shortly 
to  be  described,  and  presenting  a closely  allied  structure,  is  opposed  to  the  supposi- 
tion, and  supports  the  idea,  that  the  scale  of  Megalichthys,  complicated  as  it  is,  has 
been  wholly  formed  by  the  successive  organization  and  inflexion  of  layers  of  mem- 
brane in  which  the  granules  of  calcareous  matter  have  been  subsequently  diffused. 

Diplopterus. — M.  Agassiz  has  already  examined  some  species  from  the  old  red 
sandstone.  He  remarks,  “ Les  ecailles  presentent  une  fine  granulation  provenant 
d’une  quantite  de  petits  trous  qui  s’ouvrent  de  passage  pour  les  nombreux  petits 
vaisseaux  sanguins  qui  traversaient  I’ecaille  pour  se  rendre  dans  fepiderme.  Exa- 
minees au  microscope,  les  Readies  presentent  une  epaisse  couche  d’email,  au  dessous 
de  laquelle  se  trouve  un  tissu  osseux  montrant  des  reseaux  fort  elegants,  qui  ne  dif- 
ferent de  ceux  de  Polypt^re  que  par  leur  developpement  considerable.  Les  trous  et 
les  canaux  medullaires  I’emportent  de  beaucoup  sur  les  piliers  intermediaires*.” 

Fig.  20  represents  a horizontal  section  of  a very  thin  scale  belonging  to  an  unde- 
scribed species  from  the  coal-field  near  Leeds.  The  original  specimen  was  about 
half  an  inch  in  length,  and,  as  in  Megalichthys,  was  covered  with  shining  ganoin, 
which  was  perforated  by  innumerable  minute  apertures,  the  orifices  of  canals.  The 
section  was  made  at  a slightly  inclined  angle  to  the  plane  of  the  scale,  so  that  whilst 
the  extremity  a cuts  obliquely  through  the  superficial  ganoin  and  its  subjacent  kos- 
mine,  the  opposite  end  b,  especially  to  the  right-hand  of  the  figure,  dips  more  deeply 
into  the  bony  tissue  of  the  scale.  Though  I have  not  been  able  to  procure  a second 
example  of  this  scale,  in  order  to  make  a vertical  section,  there  is  no  difficulty  in 
reading  off  its  beautiful  structure,  and  comparing  it  with  the  vertical  sections  of 
Megalichthys  and  Holoptychius.  It  corresponds  exactly  with  what  has  already  been 
described  as  the  immature  condition  of  the  former,  and  closely  resembles  that  pre- 
sented by  one  species  of  the  latter. 

c is  the  superficial  layer  of  the  kosmine  supporting  an  exceedingly  thin  film  of 
ganoin  ; the  dark  portion  d is  the  horizontal  cavity,  traversed  by  the  hollow  pillars 
of  kosmine,  e,  which  surround  the  trumpet-shaped  descending  cavities:  these  com- 
mence by  small  apertures  in  the  superficial  layer,/*;  at  e they  gradually  enlarge,  be- 
coming angular  at  g,  and  at  h giving  off  the  minute  connecting  tubes  i,  which  cor- 
respond with  those  of  the  Megalichthys,  fig.  15  c.  Below  this  the  descending  cavities 
become  lost  in  the  ramifications  of  the  Haversian  canals  I,  as  at  h.  The  small  tubes 
i divide  the  kosmine  into  areolar  spaces,  and  into  the  centre  of  each  there  arises  an 
offshoot  from  the  Haversian  canals,  m,  opening  superiorly  into  the  horizontal  cavity  d, 

* Poissons  de  Vieux  Gr^s  Rouge,  p.  54. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  457 


which  separates  the  upper  layer  of  the  kosmine  from  the  tissues  below.  As  vve 
have  already  seen  to  be  the  case  with  Megalichthys,  neither  the  descending  cavities 
€,g,  nor  the  small  tubes  i into  which  they  subdivide,  give  off  any  minute  tubuli,  but 
their  walls  are  wholly  supplied  either  from  the  superficial  space  d,  or  from  the  cavity 
in  the  centre  of  each  areola,  m.  The  latter  especially  give  off  branching  kosmine 
tubuli  of  considerable  size  and  great  beauty.  In  the  former  the  tubuli  are  very  small, 
with  the  exception  of  those  which  ascend  to  the  superficial  layer  c,  which  are  thicker 
and  more  branched.  In  the  hollow  pillars,  e,  these  tubes  are  uniformly  parallel,  ra- 
diating inwards.  As  in  Megalichthys,  all  the  tissues  in  the  plane  of  and  above  the 
small  inosculating  tubes  i,  consist  of  kosmine,  excepting  the  thin  superficial  layer  of 
ganoin. 

The  tissues  surrounding  the  Haversian  canals,  which  are  rather  large,  are  osseous, 
presenting  the  same  appearances  as  those  of  Megalichthys.  The  inferior  laminae  of 
the  scale  also  are  horizontal  and  parallel,  presenting  the  characteristic  fusiform  or 
linear  lacunae  represented  by  fig.  19. 

A vertical  section  of  another  scale  already  alluded  to,  also  from  Leeds,  slightly 
differs  from  the  last.  The  upper  layer  of  the  kosmine  is  thicker,  and  from  the  vertical 
cavities  entering  it  but  a small  distance  before  giving  off  the  inosculating  tubes,  20  i, 
it  would  be  impossible  by  any  horizontal  section  to  exhibit  the  elegant  rings  seen 
in  20  e.  The  Haversian  canals  are  more  like  the  large  cancelli  in  the  diploe  of  bone, 
and  the  branches  which  they  send  up  into  the  kosmine  are  equally  large ; illus- 
trating the  description  given  of  the  development  of  the  scale  of  Megalichthys. 

Holoptychius. — The  structure  of  some  scales  from  the  old  red  sandstone,  belonging 
to  this  genus,  has  been  already  described  by  M.  Agassiz*.  His  results,  however, 
differ  in  many  material  points  from  those  obtained  by  my  own  observations  upon 
scales  belonging  to  the  same  genus  from  the  upper  coal-measures  of  Lancashire,  where 
at  least  two,  if  not  more,  species  exist,  which  have  hitherto  been  confounded  under  the 
name  of  H.  sauroides. 

These  scales  vary  from  being  nearly  orbicular  to  being  so  elongated,  that  their  larger 
diameter  becomes  three  or  four  times  greater  than  the  opposite  one.  In  all  cases  one 
extremity  is  more  pointed  than  the  other,  the  latter  being  not  unfrequently  cordate. 
Their  inferior  surface  is  usually  the  only  one  seen,  the  upper  one  being  adherent  to 
the  matrix.  Fig.  21  represents  the  usual  aspect  of  the  latter,  and  fig.  22  of  the  former, 
amongst  the  larger  scales  of  H.  sauroides.  Both  surfaces  exhibit  the  concentric  lines 
noticed  by  M.  Agassiz  as  ‘‘  repetant  les  contours  de  I’ecaille.”  These  are  the  most 
beautifully  regular  and  definite  on  the  upper  surface,  especially  at  its  anterior  extre- 
mity, 21  a,  but  towards  the  pointed  end,  h,  they  give  place  to  others  of  a larger  size, 
but  which  are  less  numerous  as  well  as  less  regular  in  their  distribution.  When 
the  scale  was  in  situ,  the  latter  occupied  the  exposed  portion,  the  remainder  being 
covered  over  by  the  pointed  extremities  of  the  two  scales  in  front  of  it ; these  con- 
* Poissons  de  Vieux  Gr^s  Rouge,  p.  70,  tab.  24,  fig.  10. 


458  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


centric  ridges  are  traversed  at  the  two  extremities,  but  especially  at  the  posterior 
one,  b,  by  minute  radiating  lines  ; at  the  two  sides  of  the  scale  they  are  not  visible. 
On  the  inferior  surface  the  concentric  lines  extend  over  two-thirds  of  the  scale,  fig.  22, 
but  they  are  less  regularly  definite  and  uniform  in  their  thickness  than  on  the  oppo- 
site side.  We  find  none  of  the  radiating  lines  which  M.  Agassiz  noticed  in  the  corre- 
sponding portion  of  the  scales  from  the  old  red  sandstone,  but  its  acuminated  extre- 
mity, 22  a,  corresponding  to  21  a,  exhibits  a number  of  large  puncta,  22  c,  which  are 
the  orifices  of  ascending  canals.  On  making  a vertical  section  of  one  of  these  scales, 
I found  few  traces  of  either  kosmine  or  ganoin ; it  consisted  of  numerous  lamellae, 
the  lower  ones  resembling  those  seen  in  the  corresponding  portion  of  Megalichthys. 
These  are  shown  in  fig.  23  a,  which  represents  a vertical  section  of  a large  scale, 
taken  in  the  direction  of  the  dotted  line  c in  fig.  22.  These  lamellae  are  furnished 
with  lacunae  and  canaliculi  like  those  of  Megalichthys  and  Diplopterus,  fig.  19.  The 
upper  portion  of  the  scale  consists  of  the  upturned  lamellae,  which  by  their  inflexions 
form  the  ridges  which  ornament  its  external  surface,  23  b.  In  the  section  represented 
in  the  Plate,  these  ridges  are  less  striking  and  prominent  than  ordinary ; generally, 
instead  of  the  section  presenting  a gently  undulating  outline,  these  ridges  are  irre- 
gular and  even  overhang  the  furrows  which  separate  them,  but  still  consist  of  the 
inflected  extremities  of  the  lamellae,  as  do  also  the  fine  radiating  lines  of  fig.  21. 

Under  these  ridges,  at  the  anterior  part  of  the  scale,  we  find  a series  of  concentric 
canals,  connected  together  by  short  anastomosing  branches.  They  do  not  follow  any 
very  uniform  direction  in  their  distribution,  varying  considerably  in  the  details  of 
their  arrangement,  always  however  showing  a tendency  to  be  regulated  by  the  direc- 
tion of  the  lamellae  themselves,  they  having  evidently  been  formed  on  the  principle 
seen  in  the  scale  of  the  Sturgeon ; thus  in  the  section  fig.  23,  we  find  that  many  of 
the  branches  of  these  canals  exhibit  a curvilinear  arrangement,  23  c,  their  direction 
corresponding  with  that  of  the  lamellae.  From  these  Haversian  canals  are  given  off 
numerous  vertical  branches,  especially  at  the  acuminated  extremity  of  the  scale. 
Those  which  ascend,  open  in  the  grooves  separating  the  concentric  ridges,  fig.  23  d, 
whilst  the  orifices  of  the  descending  ones  produce  the  puncta  seen  at  fig.  22  c.  These 
vertical  canals  have  not  been  formed  by  inflexions  of  the  lamellae,  but  by  the  leaving 
out  of  the  apposite  portions  of  each  succeeding  lamella  as  it  was  organized ; con- 
sequently they  merely  pass  through  the  latter  nearly  at  right  angles  to  their  plane. 

The  whole  texture  of  the  scale  is  crowded  with  various  modifications  of  lacunae, 
from  the  fusiform  ones  already  described  to  those  of  the  ordinary  ichthyal  type  ; and 
though  many  of  their  canaliculi  traverse  the  lamellae,  they  are  chiefly  developed 
parallel  with  these  layers,  and  follow  their  direction. 

In  the  species  examined  by  M.  Agassiz,  that  philosopher  found  a structure  very 
similar  to  the  one  just  described ; he  applies  the  term  enameled  {dmailUe)  to  the 
layers  constituting  the  external  ornaments  of  the  scale,  at  the  same  time  however 
observing,  that  they  are  “ qu’une  substance  osseuse  plus  epaisse,  dans  laquelles  les 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  459 


couches  sont  efFacees,  et  les  corpuscules  plus  grandes.”  M.  Agassiz  also  notices 
radiating  lines  crossing  the  concentric  ones,  but  he  describes  them  as  forrnees  par 
de  petits  canellures  tres  fines  et  a peine  en  relief,  dans  lesquels  se  fixaient  probable- 
ment  les  fibres  de  la  peau.”  In  H.  sauroides,  as  we  have  seen,  the  inferior  surface  ex- 
hibits none  of  these  lines ; and  in  the  upper  layers  the  lamellae  are  not  effaced,  though 
the  structure  is  dense.  I have  not  unfrequently  observed,  in  some  of  the  projecting 
ridges,  a slight  disposition  towards  the  development  of  kosmine  tubes,  as  if  nature 
was  making  her  earliest  efforts  at  converting  the  true  osseous  lamellae  into 
kosmine. 

The  preceding  description,  which  applies  to  the  majority  of  the  scales  of  Holopty- 
chius  which  I have  examined,  reveals  to  us  many  points  of  remarkable  identity  be- 
tween them  and  those  of  Megalichthys  and  Dlplopteriis,  indicating  a much  closer 
afiinity  between  these  three  genera  than  has  hitherto  been  recognised.  The  exami- 
nation of  one  oblong  scale  belonging  to  an  undoubted  species  of  Holoptychius  from 
the  upper  coal  shales  of  Lancashire,  establishes  this  affinity  still  more  strongly.  Its 
inferior  surface  exhibited  the  same  appearance  as  H.  sauroides ; smooth  concentric 
lines  existing  at  its  rounded  extremity,  whilst  the  acuminated  one  was  studded  with 
large  puncta.  But  on  making  a vertical  section,  a striking  difference  presented  itself 
in  the  superior  surface,  which,  being  adherent  to  its  matrix,  could  not  previously  be 
seen.  The  rounded  extremity  exhibited  the  structure  seen  in  the  corresponding 
part  of  H.  sauroides.  The  inferior  layers  of  the  opposite  extremity  also  correspond, 
fig.  24  a.  The  puncta  open  into  ascending  canals,  which  perforate  the  laminm,  24  b, 
and  communicate  superiorly  with  a system  of  canals  or  cavities,  24  d,  analogous  to 
those  of  the  Diplopterus,  fig.  20  d,  to  the  appearance  that  would  be  presented  by  a 
vertical  section  of  which  this  form  of  Holoptychius  forms  an  excellent  illustration. 
Above  and  around  this  superficial  cavity,  24  d,  is  a development  of  kosmine,  which  is 
penetrated  from  above  by  trumpet-shaped  cavities,  24  e,  and  which  give  off  small 
connecting  tubes,  24  f,  transverse  sections  of  which,  coming  from  the  more  distant 
cavities  not  cut  across  by  the  section,  are  seen  at  g.  These  trumpet-shaped  cavities 
are  not  quite  so  gracefully  formed  as  in  Megalichthys,  but  in  other  respects  they  are 
very  similar.  After  giving  off  these  tubes,  the  cavities  spread  out  continuously  in 
every  direction  over  the  osseous  tissue,  and  send  up  into  each  areola  formed  by  the 
network  of  tubes,  an  expansion,  24  h,  analogous  to  the  cul-de-sacs  of  Megalichthys, 
but  which,  instead  of  being  isolated  as  in  that  genus,  in  the  mature  state  of  this  Ho- 
loptychius all  open  into  one  another,  as  seen  at  the  extremity  of  the  scale,  d-,  the  only 
connecting  portions  between  what  may  be  regarded  as  the  roof  and  the  floor  of  this 
space  being  the  hollow  pillars  surrounding  the  cavities,  e.  As  in  Diplopterus,  the 
whole  of  the  kosmine  receives  its  minute  tubuli  from  this  large  superficial  space,  from 
which  they  radiate  in  every  direction. 

This  section  also  explains  what  has  been  already  said  respecting  the  growth  of  the 
kosmine  in  Megalichthys.  Its  permanent  structure  in  Holoptychius  presents  the  con- 
dition which  has  obviously  existed  in  the  young  state  of  the  scale  in  that  genus.  On 


460  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


comparing  figs.  15  and  24  together,  and  bearing  in  mind  the  concentric  lines  in  the 
kosmine  of  the  former,  this  identity  will  be  obvious  at  a glance ; and  it  will  be  seen 
how  the  addition  of  successive  lamellm  to  such  a framework  as  fig.  24  exhibits,  would 
lead  to  all  the  results  which  we  find  in  Megalichthys,  and  also  establishes  the  close 
connection  that  exists  between  the  two  genera,  as  well  as  between  them  and  Diplo- 
pterus;  instead  of  one  being  found  amongst  the  Coelacanths,  and  the  other  two  amongst 
the  Sauroids,  this  resemblance,  connected  with  the  close  analogy  existing  between 
their  teeth  and  such  fragments  of  bone  as  have  been  met  with,  requires  that  they 
should  in  future  be  classed  side  by  side. 

No  doubt  can  exist  that  in  these  species  of  Holoptychius,  the  bony  lamellae  have 
been  deposited  on  the  same  plan  that  we  have  found  to  prevail  throughout  all  the 
forms  of  scale  which  I have  examined.  This  is  especially  seen  in  fig.  23.  The  exist- 
ence of  the  Haversian  canals  can  be  distinctly  traced,  either  to  the  inflexions  of 
these  lamellae,  or  to  the  leaving  out  of  portions  of  them,  as  in  the  case  of  the  vertical 
branches. 

Bearing  in  mind  the  close  affinity  just  noticed,  between  the  genus  under  consi- 
deration and  Megalichthys,  we  can  scarcely  suppose  it  probable  that  their  scales  have 
been  constructed  on  two  widely  different  physiological  plans.  That  of  Holoptychius 
appears  to  be  intermediate,  as  to  the  complexity  of  its  structure,  between  those  of 
Acipenser  and  Megalichthys ; consequently  we  can  scarcely  resist  the  conclusion,  to 
which  the  study  of  the  latter  fish  alone  has  led  me  to  incline,  that  complicated  as  its 
scales  are,  they  have  been  formed,  ab  initio,  on  the  same  plan  of  intramembranous 
ossification  as  all  the  rest. 

Judging  from  the  descriptions  given  by  M.  Agassiz,  it  appears  evident  that  a re- 
cent example  of  a scale  somewhat  similar  to  the  type  found  in  Holoptychius,  occurs 
in  the  Polypterus  of  the  Nile.  Though  in  his  description  M.  Agassiz  does  not  notice 
anything  analogous  to  the  forms  of  kosmine  described  in  the  last  genera,  yet  in  the 
horizontal  network  of  canals,  and  their  vertical  branches  communicating  with  both 
the  upper  and  lower  surfaces,  we  have  an  analogy  too  evident  to  be  overlooked ; and 
one  which  attracted  the  attention  of  the  Swiss  philosopher,  whilst  examining  some 
of  the  Diplopteri  from  the  old  red  sandstone.  It  is  highly  interesting  to  find,  that, 
though  we  have  so  small  a number  of  ganoid  fish  still  existing,  when  compared  with 
the  multitudes  which  crowded  the  ancient  seas  of  our  globe,  we  have,  in  the  Bony 
Pike,  the  Sturgeon  and  the  Polypterus,  living  representatives  of  the  most  conspicuous 
types  of  scale-structure  found  amongst  their  fossil  allies. 

Macropoma. — This  anomalous  genus  has  long  been  a source  of  perplexity  to 
ichthyologists.  Macropoma  Mantelli,  first  discovered  in  the  Sussex  chalk  by  the 
distinguished  geologist  whose  name  it  bears,  was  first  arranged  by  M.  Agassiz 
amongst  the  sauroid  subdivision  of  the  ganoid  fish.  He  afterwards  removed  it  to  the 
Coelacanths,  and  still  more  recently  he  has  proposed  to  unite  it  with  the  genus  Undina 
of  Munster  and  some  others,  of  which  he  designed  to  form  a new  group*.  On 

% 


* Poissons  Fossiles  de  Vieux  Gres  Rouge,  p.  61. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  461 


examining  a portion  of  the  opercular  scale  of  this  fish,  I found  it  to  be  studded  over 
with  tubercles,  fig.  25  a,  like  those  in  a piece  of  shagreen.  On  grinding  away  the 
under  surface,  so  as  to  render  the  upper  part  transparent,  there  appeared  beneath 
each  tubercle  a large  lenticular  cavity,  fig.  25  &,  which,  as  we  shall  subsequently  show, 
is  homologous  with  the  pulp-cavity  of  the  dermal  teeth  of  placoid  fish.  From  each 
cavity  is  given  off  a number  of  small  tubular  canals,  fig.  25  c,  which  radiate  outwards 
and  upwards,  and  communicate  with  the  external  surface  of  the  scale.  The  posterior 
portion  of  each  tubercle,  25  d,  is  more  prominent  than  its  opposite  extremity,  evincing 
a disposition  to  become  pointed  and  grooved  on  its  surface.  The  tissue  surrounding 
the  bases  of  these  tubercles  is  studded  with  numerous  lacunae  and  a few  scattered 
points,  25  e,  constituting  the  orifices  of  canals  which  come  up  from  below.  On  making 
a vertical  section  of  the  specimen,  fig.  26,  I found  that  the  tubercle  surmounting  each 
cavity,  fig.  26  a,  was  composed  of  kosmine  with  exceedingly  fine  branched  tubes,  26  b, 
radiating  from  the  cavity,  26  c,  and  covered  over  with  and  merging  in  a layer  of 
transparent  ganoin,  2Qd,  which  on  its  posterior  margin  exhibited  the  irregular  super- 
ficial grooves  already  noticed.  The  kosmine  consisted  of  a number  of  very  dense  but 
still  distinct  lamellae,  arranged  in  concentric  lines,  which,  superiorly,  followed  the 
curved  outline  of  the  tooth,  and  inferiorly,  that  of  the  roof  of  the  subjacent  cavity. 
Beneath  each  tubercle  is  this  lenticular  pulp-cavity,  figs.  25  h,  26  h,  the  radiating  pro- 
longations of  which,  25  c,  26  e,  proceeding  upwards  and  outwards,  form  channels  of 
communication  with  the  external  surface,  reminding  us  of  those  existing  in  connec- 
tion with  similar  tubercles  on  the  scale  oi  Dapidius  granulosus. 

The  textures  which  give  support  to  these  tooth-like  appendages,  consist  of  a series 
of  osseous  laminae,  fig.  26  f,  which  are  again  subdivided  into  numerous  minute  lamellae. 
Amongst  the  inferior  laminae  are  a number  of  very  large  cavities,  which  run  into  each 
other  by  means  of  narrow  connecting  passages,  forming  the  homologues  of  Haversian 
canals,  fig.  26  g.  They  send  up  narrow  vertical  branches  to  the  external  surface, 
which  generally  open  at  the  small  apertures,  25  e,  but  occasionally  unite  with  one  of 
the  canals  radiating  from  the  lenticular  pulp-cavities,  fig.  26  A. 

The  lowermost  osseous  laminae  are  not  so  thick,  individually,  as  the  upper  ones, 
but  they  are  more  regularly  uniform  in  size,  as  well  as  more  parallel  with  the  inferior 
surface,  and  with  one  another. 

Between  the  lamellae  is  a copious  distribution  of  lacunae,  many  of  the  canaliculi  of 
which  radiate  vertically  as  well  as  horizontally,  perforating  the  lamellae,  and  thus 
establishing  a communication  between  contiguous  layers  of  lacunae. 

The  specimens  which  I have  had  the  opportunity  of  examining  exhibited  no  trace 
of  upturned  lamellae  in  any  part  of  their  course,  though  their  inflexions  appear  to 
have  formed  the  large  Haversian  cavities,  fig.  26 g.  It  is  possible,  however,  that 
they  may  do  so  at  tlie  margin  of  the  operculum,  a portion  which  I have  had  no  oppor- 
tunity of  investigating,  and  which  requires  further  attention. 

In  addition  to  the  canaliculi  of  the  lacunae,  we  also  find  a considerable  supply  of 

MDCCCXLIX.  3 o 


462  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


what  appear  to  be  lepidine  tubes,  ascending  from  the  inferior  surface  to  the  upper- 
most layers  of  the  structure,  fig.  26  h. 

The  general  aspect  of  the  exterior  of  the  body  of  Macroipoma  Mantelli,  is  that  of 
an  ordinary  scaled  fish.  This  is  especially  shown  in  a fine  specimen,  formerly  in  the 
collection  of  Dr.  Mantell,  and  now  in  the  British  Museum ; originally  figured  by 
that  gentleman  in  his  work  on  the  Fossils  of  the  South  Downs,  and  afterwards  by 
M.  Agassiz*.  Specimens  exhibiting  the  exterior  of  the  fish  are  very  rare,  since, 
owing  to  the  roughness  of  the  outer  surface  of  the  scales,  they  are  usually  adherent 
to  the  matrix,  the  inner  portion  being  exposed ; or,  what  is  even  more  frequently  the 
case,  each  scale  has  split  horizontally,  and  only  exhibits  its  internal  tissues. 

According  to  the  enlarged  figures  of  M.  AGASSiz-f,  the  anterior  part  of  the  upper 
surface  of  each  scale  is  marked  with  concentric  lines,  which  he  regards  as  lines  of 
growth  ; whilst  the  posterior  or  visible  portion  is  crowded  with  elongated  tubercles, 
or  pointed  cylinders  ; those  on  the  centre  of  each  scale  being  the  largest.  On  making 
a very  careful  examination  of  the  surface  of  these  scales,  I found  that  the  tubercles,  the 
“cylindres  pointus”  of  Agassiz,  were  dermal  teeth,  corresponding  with  those  already 
described  as  existing  on  the  opercular  scale;  instead  however  of  being  nearly  orbi- 
cular as  in  that  example,  they  are  all  more  or  less  elongated,  whilst  some  of  them, 
and  especially  four  or  five  large  ones  ranged  along  the  middle  of  many  of  the  scales, 
stand  up  in  bold  relief,  appearing  like  well-defined  pointed  teeth,  equal  in  their  degree 
of  development  to  any  which  I have  seen  in  the  skins  of  recent  Placoids.  The  pulp- 
cavity  is  similarly  elongated,  still  however  giving  off  the  radiating  canals  at  its  base. 
These  latter  frequently  communicate  between  one  cavity  and  another. 

Each  of  the  teeth  is  irregularly  grooved  on  its  external  surface,  and  these  grooves, 
being  prolonged  in  irregularly  parallel  lines  on  the  broad  thin  expansions  into  which 
the  bases  of  the  teeth  spread  out,  give  to  them  somewhat  the  appearance  of  con- 
centric striae.  In  none  of  those  which  I have  seen  have  I been  able  to  discover  the 
regularly  concentric  arrangement  shown  in  the  figures  of  M.  Agassiz.  Plate  XLIII. 
fig.  2/  represents  a vertical  section  of  the  greater  part  of  a scale  in  which  the  tubercles 
are  very  small,  but  in  which  the  lower  tissues  appear  to  be  complete;  27/*  is  the 
posterior  extremity  of  one  scale  resting  upon  the  anterior  margin,  27 g of  another; 
a small  portion  of  the  posterior  extremity  of  the  latter  is  still  wanting. 

The  textures  exhibited  in  this  section  are  divisible  into  two  portions,  an  upper  and 
a lower  one.  The  former,  fig.  27  «,  is  of  a dense  structure,  and  appears  mainly  to  con- 
sist of  the  expanded  bases  of  the  tooth-like  tubercles  in  which  some  few  lacunae  are 
developed.  In  this  the  tubercles  are  implanted,  27  h,  each  of  which  corresponds  in  its 
general  structure  vvith  those  already  described  from  the  opercular  scale,  fig.  26  a,  only 
in  this  instance  they  are  more  depressed,  and  the  pulp-cavity  is  larger  in  proportion  to 
the  size  of  the  tubercle.  The  concentric  lamellae  of  the  kosmine  are  also  seen  com- 
pletely to  surround  the  pulp-cavity,  being  continuously  developed  to  some  extent  be- 
* Poissons  Fossiles,  vol.  ii.  tab.  65  b.  f JJt  supra,  tab.  65  b. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  463 


low  as  well  as  above  it.  Similar  canals  communicate  between  the  pulp-cavity  and  the 
upper  surface,  fig.-  27  d.  Beneath  this  superficial  tissue  we  find  another  structure, 
composed  of  numerous  thin  parallel  lamellae,  which  gradually  ascend  as  they  proceed 
from  the  anterior  towards  the  posterior  margin  of  the  scale,  fig.  27  e;  and  upon  the 
outcropping  edges  of  which,  to  employ  a geological  illustration,  the  more  superficial 
layer  rests  in  unconformed  stratification.  No  true  lacunae  appear  to  enter  into  the 
structure  of  these  lamellae,  but  between  them  are  layers  of  small  irregular  tubes, 
which  anastomose  freely  with  one  another  ; those  found  on  opposite  sides  of  each 
lamella,  like  the  fusiform  lacunae  of  IMegalichthys,  usually  running  in  different 
directions,  so  as  to  give  to  the  horizontal  section  the  aspect  of  network.  These  do 
not  appear  to  be  modified  lacunae,  but  seem  more  analogous  to  lepidine  tubes. 
They  give  off  numerous  branches,  which  pass  through  the  lamellae,  keeping  up  a 
communication  between  contiguous  layers. 

Fig.  28  is  a section  of  one  of  the  rows  of  large  teeth  from  the  centre  of  the  scale. 
In  this  specimen,  from  which  the  lower  laminae  have  been  accidentally  detached,  as 
is  usually  the  case,  the  tubercles  are  developed  into  the  form  of  regular  pointed 
dermal  teeth,  each  having  a pulp-cavity,  fig.  28  a,  from  which  spring  small  branching 
tubes,  28  b,  like  those  seen  in  the  dermal  teeth  of  ordinary  Placoids.  Each  one  ex- 
hibits a laminated  structure  like  that  seen  in  the  true  teeth  of  reptiles,  the  lamellae 
being  arranged  as  a succession  of  cones,  having  evidently  been  formed  by  the  addi- 
tion of  new  internal  layers  organized  around  the  soft  pulp.  In  fact,  it  is  only  one 
of  the  laminated  tubercles  of  the  operculum,  fig.  26  a,  drawn  out  vertically;  the  len- 
ticular space,  fig.  26  c,  being  also  elongated  in  the  form  of  a true  pulp-cavity,  whilst, 
in  consequence  of  this  modification  of  the  external  contour,  the  lamellae  have  assumed 
the  appearance  of  a succession  of  cones  inclosing  each  other.  At  the  base  of  each 
tooth  we  still  find  the  radiating  canals,  fig.  28  J,  communicating  with  the  exterior  of 
the  scale,  as  in  those  of  the  operculum. 

Fig.  28  e represents  the  externally  grooved  appearance  of  each  tooth,  the  section 
not  having  passed  completely  through  its  centre. 

The  most  extraordinary  feature  in  the  anatomy  of  this  singular  fish  yet  remains  to 
be  described.  In  its  interior  there  is  invariably  found  a long  hollow  fusiform  viscus, 
which  has  generally  been  regarded  as  a stomach.  M.  Agassiz,  who  entertained  this 
opinion,  says,  “II  ressemble  a un  cylindre  squammeux,  et  cet  aspect  est  evidemment 
le  resultat  des  changemens  survenus  dans  les  ditferentes  membranes  qui  en  com- 
posaient  les  parois.” 

On  mounting  prepared  sections  of  this  “membrane,”  I found  that  it  consisted  of 
true  laminated  bony  tissue.  When  a vertical  section  was  made  through  its  entire 
thickness  parallel  to  the  long  axis  of  the  viscus,  it  presented  the  appearance  repre- 
sented in  fig.  30.  It  chiefly  consists  of  horizontal  lamellse,  fig.  30  a,  between  which 
are  developed  large  lacunae,  fig.  30  h,  identical  with  those  found  in  the  bones  of  its 

3 o 2 


464  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


endo-skeleton.  These  lacunae  not  only  distribute  their  large  canaliculi  in  the  plane 
of  the  lamellae,  but  shorter  vertical  twigs  penetrate  the  lamellae,  and  thus  keep  up  a 
communication  between  the  inner  and  outer  surfaces  of  the  viscus. 

Some  of  the  external  lamellae  lose  their  exact  parallelism  with  those  below,  and 
one  in  particular  assumes  an  undulatory  arrangement,  fig.  30  c,  in  the  folds  of  which, 
alternately  above  and  below,  are  placed  large  irregularly-shaped  lacunae,  fig.  30  d, 
the  distorted  prolongations  from  which  are  obviously  modified  canaliculi.  This 
curious  structure  is  covered  over  with  other  more  dense  and  apparently  structureless 
lamellae,  which  fill  up  the  inequalities  and  restore  the  parallelism  of  the  surface  with 
the  lower  lamellae,  constituting  the  exterior  of  the  viscus. 

On  examining  a horizontal  preparation  of  a fragment  of  the  same  viscus,  we  see 
that  the  undulations  of  the  lamella,  fig.  30  c,  produce  the  appearance  exhibited  by 
fig.  29.  Numerous  parallel  lines  enclose  corresponding  spaces,  about  the  T^o^th  of 
an  inch  in  width,  which  circumscribe  the  viscus  at  right  angles  to  its  longer  diameter. 
The  lacunae,  fig.  29  a,  which  are  arranged  in  corresponding  rows,  are  alternately 
above  and  below  the  lamella,  their  irregularly  projecting  canaliculi,  29  h,  giving 
them  the  aspect  of  Hebrew  or  Arabic  characters.  On  making  a horizontal  section 
amongst  the  lower  lamellae,  30  a,  we  find  that  the  numerous  lacunae  are  of  the  com- 
mon ichthyal  type,  only  they  are  more  than  usually  crowded  together,  as  well  as 
anastomose  more  freely  through  their  spider-like  lacunae.  No  canals  of  any  kind 
pass  through  the  tissue.  These  facts  of  course  do  away  with  all  probability  of  this  ano- 
malous viscus  having  been  a stomacb  ; according  to  Dr.  Mantell,  to  whom  we  are 
indebted  for  the  discovery  of  this  singular  creature,  the  broad  anterior  extremity  of 
the  cylinder  is  always  open,  and  situated  opposite  the  posterior  margin  of  the  oper- 
cular bone,  whilst  its  caudal  termination  is  as  invariably  closed. 

I am  disposed  to  believe  that  it  has  been  an  organ  fulfilling  the  functions  of  an 
air-bladder.  Its  osseous  structure  would  render  it  capable  of  resisting  a considerable 
amount  of  pressure,  and  if  its  patulous  extremity  has  been  closed  up  by  an  elastic 
membranous  appendage,  capable  of  acting  as  a valve,  this  would  enable  the  creature 
to  regulate  its  buoyancy  by  increasing  or  diminishing  the  compression  of  the  con- 
tained air,  and  thus  facilitate  its  movements  in  either  shallow  water  or  at  great 
depths.  Except  in  cases  of  diseased  ossification,  the  existence  of  an  internal  thoracic 
or  abdominal  viscus,  having  hard  parietes  of  true  bone,  is  an  anomaly,  which,  as  far 
as  I am  aware,  has  hitherto  presented  no  parallel  in  nature. 

The  structure  of  the  scale  of  Macropoma,  as  now  described,  is  wholly  different 
from  that  presented  by  any  of  the  ganoid  fish  noticed  in  the  preceding  pages.  It 
bears  a much  closer  resemblance  in  its  leading  points  to  the  dermal  appendages 
found  amongst  the  group  of  true  Placoids,  between  which  and  the  Ganoids  the 
Macropoma  appears  to  form  an  inosculating  link.  In  order  to  illustrate  this  opinion, 
I have  accompanied  the  memoir  by  figures  of  portions  of  the  dermal  appendages  of 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  465 


one  or  two  Placoids,  which  will  enable  us  better  to  comprehend  the  structure  and 
affinities  of  this  singular  creature. 

Fig-.  31  represents  a thin  horizontal  section  of  the  shagreen  or  skin  of  the  Dog-fish. 
It  consists,  as  is  well  known,  of  a number  of  small  dermal  teeth,  implanted  in  a 
more  or  less  linear  manner  in  a soft  skin,  figs.  31  a,  ‘62  a.  Each  tooth  contains  a 
pulp-cavity,  fig.  31  b,  from  which  radiate  several  large  canals.  One  of  these  descends 
vertically,  as  seen  in  fig.  32  b,  which  represents  a vertical  section  of  an  individual 
tooth.  The  remainder,  varying  in  number  from  one  to  three  or  four,  proceed  in  a 
horizontal  direction  towards  the  posterior  portion  of  the  tooth,  figs.  31  c,  32  c,  where 
they  appear  to  communicate  with  the  most  superficial  layers  of  the  integument,  if 
not  with  the  external  surface  itself,  being  apparently  the  analogues  of  the  radiating 
canals  in  the  tubercles  and  teeth  of  Macropoma,  figs.  25  c,  26  e,  27  d and  28 

From  each  pulp-cavity  is  also  given  off  numerous  branching  tubes  like  those  seen 
in  the  dentine  of  the  teeth  of  sharks.  They  only  differ  from  those  in  the  correspond- 
ing dermal  teeth  of  Macropoma  in  being  larger  and  less  crowded  together. 

The  superficial  portion  of  each  of  these  appendages,  which  is  not  imbedded  in 
the  soft  cutaneous  tissues,  is  covered  over  with  a very  thin  layer  of  glossy 
ganoin,  but  between  which  and  the  tubular  structure  there  is  no  distinct  line  of 
demarcation. 

If  we  compare  these  vertical  and  horizontal  sections  of  the  dermal  teeth  of  the  Dog- 
fish, figs.  3 1 and  32,  with  the  corresponding  representations  of  the  operculum  and  scale 
oi  Macropoma,  figs.  25,  26  and  28,  we  cannot  fail  to  be  struck  with  their  identity  in 
every  respect.  The  only  real  difference  appears  to  be,  that,  whilst  in  the  Dog-fish  the 
teeth  are  isolated,  being  implanted  in  a soft  integument,  in  the  Macropoma  they  are 
fixed  upon  a calcareous  basis.  In  the  case  of  the  operculum,  this  basis  consists  of  a 
true  osseous  structure ; and  in  the  scales,  though  the  true  bony  matter  has  dwindled 
down  into  the  thin  superficial  film  surrounding  the  bases  of  the  teeth,  its  place  is 
supplied  by  a thin  laminated  tissue  which  is  its  equivalent,  as  a solid  foundation  on 
which  numerous  teeth  are  aggregated,  and  which  is  probably  but  the  homologue  of 
the  thin  laminae  of  which  the  stellate  bases  of  the  dermal  teeth  of  many  Placoids  are 
composed. 

If  these  are  true  analogies  and  not  mere  resemblances,  they  afford  us  an  interest- 
ing illustration  of  the  successive  steps  in  the  development  of  the  hard  cutaneous 
covering  seen  in  the  ganoid  fish  : but  before  endeavouring  to  trace  this  development, 
I would  direct  attention  to  an  additional  link  in  the  chain  supplied  by  the  fossil 
shagreen  of  the  Hybodus  reticulatus,  from  the  lias  of  Lyme  Regis  ; a vertical  section 
of  which  is  represented  in  fig.  33. 

We  here  find  another  modification  of  the  dermal  teeth,  fig.  33  a,  with  large  pulp- 
cavities,  33  b,  and  canals  opening  laterally  as  well  as  vertically,  33  c,  communicating 
with  the  soft  tissues  in  which  the  teeth  have  been  originally  implanted.  From  these 
pulp-cavities,  also  radiate  branching  tubes  resembling  those  of  dentine.  So  far,  there 


466 


MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


is  no  material  difference  between  these  and  the  dermal  teeth  of  the  Dog-fish ; but 
beneath  them,  and  imbedded  in  the  soft  tissues  of  the  true  skin,  we  find  a vast  number 
of  small,  irregular  calcareous  nodules,  33  d,  each  of  whicli  consists  of  a series  of 
concentrically  arranged  lamellm.  They  contain  neither  lacunae  nor  visible  tubes, 
but  frequently  exhibit  small  brown  points,  which  however  may  merely  be  some  effect 
of  their  subsequent  mineralization.  Though  not  composed  of  true  bone,  these  are 
surely  to  be  regarded  as  a rudimentary  attempt  at  the  extension,  amongst  the  Placoids, 
of  that  calcareous  exo-skeleton  which  has  received  so  complete  a development  in  the 
ganoid  fish. 

We  may  now  for  a moment  retrace  our  steps  and  endeavour  to  mark  some  of  the 
successive  stages  in  the  development  of  this  portion  of  the  exo-skeleton. 

In  the  common  Thornback,  Raia  clavata,  Cuv.,  a long  central  row  of  dermal  teeth 
extends  from  the  head  to  near  the  extremity  of  the  tail.  They  exhibit  the  tubular 
structure  found  in  this  class  of  objects,  but  contain  very  little  calcareous  matter ; they 
are  scarcely  more  solid  in  their  structure  .than  the  cartilaginous  column  which  they 
surmount.  The  skin  of  the  same  fish  is  studded  over  with  still  more  minute  teeth, 
but  which  contain  much  more  earthy  matter:  we  have  however  no  trace  of  true  bone. 
Each  dermal  tooth  consists  of  a succession  of  conical  lamellse  placed  one  upon 
another ; the  apex,  which  rises  above  the  cuticle,  resembles  that  of  the  Dog-fish  in 
structure ; inferiorly,  these  lamellae  expand  into  a stellate  base,  in  which  portion  they 
are  much  less  consolidated,  considerable  spaces  occasionally  existing  between  indivi- 
dual layers  after  they  have  been  artificially  dried.  The  pulp-cavity  is  quite  open  in- 
feriorly, there  being  no  extension  of  the  lamellae  across  its  base,  and  consequently  no 
necessity  for  the  horizontal  canals,  which  are  wanting.  In  the  shagreen  of  the  Dog- 
fish we  have  an  advance  upon  this  structure.  The  lower  tissues  are  more  consoli- 
dated, and  present  an  extension  of  the  lamellae  across  the  base,  closing  in  the  pulp- 
cavity  as  already  described,  and  being  only  perforated  by  the  narrow  canals,  fig.  32  d. 
In  Hyhodus  reticulatus  we  find  dermal  teeth  of  a similar  type  to  those  of  the  Dog-fish, 
but  we  have  a further  development  of  calcareous  granules  in  the  subjacent  skin,  but 
no  true  bone.  In  Macropoma  we  advance  still  further.  In  each  scale  we  find  a 
laminated  texture,  probably  analogous  in  its  nature  to  the  expanded  bases  of  the 
teeth  in  the  shagreen  of  the  Thornback : upon  this  texture,  the  teeth,  no  longer 
isolated,  are  aggregated  ; whilst  on  the  surface  of  the  scale  thus  formed,  we  find,  for 
the  first  time,  a thin  film  of  true  bone.  In  the  operculum  of  Macropoma,  the  sub- 
structure upon  which  the  dermal  teeth  are  implanted  exhibits  all  the  essential  cha- 
racters of  true  bone,  its  laminated  structures  preparing  us  for  the  ganoid  fish,  where 
not  only  the  operculum  but  also  the  other  scales  are  of  an  osseous  nature.  Amongst 
these  we  still  find  scattered  dermal  teeth,  studding  the  scales  of  Dapidius  granulosus, 
presenting  the  same  external  contour,  internal  pulp-cavity,  branching  tubuli  and 
canals  communicating  with  the  exterior  as  in  the  preceding  forms. 

These  successive  steps,  conducting  us  from  the  dermal  appendages  of  the  Placoids 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  467 


to  the  ganoid  scales,  indicate  a series  of  analogies  which  can  scarcely  be  questioned. 
But  I should  even  venture  to  go  still  further ; I can  trace  no  real  difference  between 
the  tubercles  of  the  scale  of  Dapidius  granulosus,  and  what  I have  called  the  kos- 
mine,  in  Lepidotus  and  its  allies.  The  latter  appears  to  me  to  be  only  a more  ex- 
tended development  of  the  former.  In  the  beautiful  form  in  which  this  kosmine 
exists  on  the  scales  of  MegaUcJitliys,  Dlplopterus  and  Holoptychius,  we  have  nothing 
more,  apparently,  than  the  confluent  aggregation  and  superficial  depression  of  a 
number  of  placoid  teeth,  surmounting  a highly  developed  bony  scale.  Compare  for  a 
moment  the  horizontal  section  of  the  shagreen  of  the  Dog-fish,  fig.  31,  with  the  hori- 
zontal section  of  the  Dlplopterus,  fig.  20.  The  dermal  teeth  of  the  former  are  repre- 
sented by  the  areolae  of  the  latter ; the  pulp-cavity  and  branching  tubes  of  the  true 
dermal  tooth,  fig.  31  Z),  have  their  homologues  in  the  ascending  central  cavities  and 
branching  tubes  of  the  areolae  of  the  Dlplopterus,  fig.  20  m.  In  the  same  way  the 
ascending  cul-de-sac  in  each  areola  of  the  MegaUchthys  appears  to  correspond  with 
the  pulp-cavity,  whilst  the  arborescent  tubidi  which  it  gives  off  represent  the  dentine- 
like tubes  of  the  shagreen.  The  chief  difference  appears  to  consist  in  the  fact,  that 
in  the  Ganoid,  the  areolae,  being  closely  aggregated  upon  a bony  basis,  have  coalesced, 
and  been  flattened,  superiorly,  to  an  uniform  level ; whilst  in  the  Placoid,  each  areola 
forms  an  isolated  conical  tooth,  implanted  in  the  soft  integument.  The  different  de- 
grees to  which  the  same  structure  may  be  either  flattened,  or  drawn  out  and  become 
acuminate,  is  seen  in  the  various  parts  of  the  exo-skeleton  of  Macropoma,  showing 
that  the  process  is  a very  trivial  one,  involving  no  typical  change*. 

* Since  the  above  remarks  were  jjenned,  I have  found  a still  more  beautiful  illustration  of  this  homology. 
When  the  smooth  shining  membrane  covering  the  snout  of  the  Saw-fish  is  examined  under  the  microscope,  it 
is  found  to  consist  of  a thin  soft  skin,  in  which  are  implanted  numerous  flattened  dermal  teeth,  each  resembling, 
in  its  form,  the  small  studs  commonly  worn  as  breast-ornaments.  They  are  packed  closely  together,  with  only 
a few  minute  intervening  spaces.  This  closely  aggregate  arrangement,  combined  with  their  depressed  form, 
causes  the  whole  to  present  a smooth,  shining  surface,  nearly  resembling  that  of  a ganoid  scale.  Fig.  34  re- 
presents a vertical  section  of  some  of  these  teeth  with  the  subjacent  tissues ; 34  a is  the  upper  portion  of  the 
osseous  (?)  structure  of  the  snout;  b,  the  soft  integument;  c,  individual  teeth;  d,  the  pulp-cavity;  e,  canals 
radiating  from  the  latter,  from  four  to  eight  existing  in  each  tooth,  and  arranged  as  in  Macropoma,  fig.  25  ; 
/,  descending  canal,  communicating  between  the  pulp-cavity  and  the  subjacent  soft  integument ; g,  dentine- 
like (kosmine)  tubes ; h,  open  spaces  surrounding  each  tooth,  and  appearing,  when  viewed  vertically  by  trans- 
mitted light,  like  a network  of  canals,  reminding  us  most  forcibly  of  the  similar  appearance  surrounding  each 
areola  'm  MegaUchthys,  fig.  16.  Where  three  or  four  of  the  teeth  meet  there  is  usually  a minute  space  not 
filled  up,  opening  into  this  network,  which  latter  is  formed  by  the  horizontal  constriction  of  the  teeth,  as  seen 
in  34  which  represents  the  exterior  of  an  individual  which  the  section  has  not  divided. 

On  comparing  this  section  with  the  vertical  one  of  MegaUchthys,  fig.  15,  the  homologies  of  the  various  parts 
are  still  more  striking  than  in  the  example  of  the  Dog-fish.  Each  tooth  in  the  Saw-fish  represents  one  superficial 
areola  of  the  MegaUchthys.  The  small  superficial  intervals  between  the  teeth  appear  to  be  the  homologues  of 
the  descending  trumpet-shaped  cavities,  15  a;  these  communicate  between  the  exterior  and  the  interdental 
spaces,  34  h,  which  apparently  correspond  with  the  network  of  small  tubes  in  MegaUchthys,  15  c and  16  c,  as 
already  observed.  The  pulp-cavity,  34  d,  takes  the  place  of  the  cul-de-sac,  15  f,  a communication  being  main- 
tained between  the  interdental  spaces  and  these  pulp-cavities,  by  means  of  the  radiating  canals,  34  e.  And,  as 


468 


MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


This  supposed  analogy  is,  in  some  degree,  supported  by  the  resemblance  in  the  pro- 
cess by  which  the  areolae  of  Megalichthys  and  the  dermal  teeth  of  the  Placoids  are 
developed  and  increased.  In  both  examples  it  is  by  the  addition  of  new  internal 
layers  around  the  central  cavity.  The  same  is  the  case  in  the  tubercles  and  teeth  of 
Macropoma.  These  facts  (if  correctly  interpreted,  and  I believe  them  to  be  so)  con- 
firm the  necessity  of  my  proposed  restriction  of  the  terms  ganoin,  enamel  {dmail),  &c. 
Two  perfectly  distinct  structures  have  hitherto  been  comprehended  in  the  expression 

enamel,”  as  hitherto  applied  to  the  scales  of  fish,  viz.  the  superficial,  transparent, 
hyaline  tissue,  which  usually  gives  glossiness  to  the  surface  of  the  scale,  and  a sub- 
jacent one,  which  I propose  to  distinguish  by  the  name  of  kosmine^.  In  some  genera, 
such  as  Megalichthys,  this  latter  structure  is  gradually  blended  with  the  former,  the 
line  of  demarcation  not  being  visible  ; whilst  in  others,  such  as  Lepidotus,  Palceoniscus 
etc.,  it  is  perfectly  distinct  from  it,  blending  rather  with  the  subjacent  osseous 
tissue.  These  two  appear  to  be  as  distinct  as  bone  and  dentine.  The  ganoin  exhi- 
bits no  visible  trace  of  structure  beyond  its  arrangement  in  the  form  of  laininse,  and 
the  occasional  existence  of  minute  coloured  granular  points.  When  separated  from 
the  tissue  upon  which  it  rests,  it  evinces  a marked  disposition  to  crack  and  splinter  in 
every  direction.  The  kosmine,  on  the  other  hand,  in  a fossil  state  at  least,  is  usually 
coloured,  and  always  exhibits  some  arrangement  of  minute  branching  tubes,  resem- 
bling those  of  dentine ; and  as,  in  some  species  of  fish.  Prof.  Owen  has  pointed  out 
the  direct  passage  of  Haversian  canals  into  the  pulp-cavities  and  dentinal  tubes  of 
the  true  teeth,  so  in  the  kosmine  do  we  find  a direct  extension  of  the  similar  canals 
into  the  corresponding  tubular  structures  of  the  surface  of  the  scale. 

I have  seen  no  instance  in  which  this  kosmine  has  been  present  without  a covering 
of  ganoin,  whilst  the  latter  may  frequently  be  present  without  any  subjacent  kosmine. 
I am  further  led  to  conclude,  that,  whatever  name  be  ultimately  employed  to  repre- 
sent what  I have  designated  kosmine,  it  must  also  be  applied  to  those  dentine-like 
tissues,  which,  in  the  form  of  dermal  teeth,  ornament  the  skins  of  so  many  Placoids. 

If  then  I am  correct  on  these  points,  we  must  come  to  the  conclusion,  that,  whilst 
the  scales  of  many  of  the  so-called  ‘‘Ganoid  ” fish,  such  as  the  Sturgeon,  and  other 
similar  forms,  exhibit  few  or  no  traces  of  either  ganoin  or  kosmine,  many  of  the 
“Placoids”  exhibit  such  an  extensive  development  of  both,  as  finds  few  parallels 
amongst  the  Ganoids ; so  that,  not  only  have  we  several  connecting  links  merging 
tlie  two  groups  in  one  another,  more  of  which  links  doubtless  remain  to  be  dis- 
covered, but  the  distinction  of  “ Ganoid,”  as  the  term  has  hitherto  been  applied, 
ceases  to  be  a physiological  one. 

\n  Megalichthys  edich  cul-de-sac  communicates  with  the  subjacent  tissues  through  the  medium  of  the  Haversian 
canals,  so  in  the  Saw-lish  the  descending  canal,  34 f,  communicates  with  the  soft  integument,  b,  which  alone 
separates  it  from  the  curious  cancellated  structure,  a,  representing  the  bony  (?)  part  of  the  snout.  It  is  obvious 
that  we  only  require  the  upper  and  lower  disc-like  expansions  of  contiguous  teeth  to  become  confluent,  to  give 
us  a structure  closely  resembling  that  which  covers  the  bony  scales  of  Megalichthys. 

* See  page  442. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  469 


Another  conclusion  to  be  drawn  from  the  foregoing  observations,  is  the  corrobora- 
tion of  a portion  of  the  views  of  M.  Agassiz  in  reference  to  the  mode  of  growth 
which  has  obtained  amongst  the  scales  of  “ ganoid  fish,”  viz.  that  it  has  been  accom- 
plished by  the  addition  of  new  lamellae  applied  to  their  exterior*  : but  these  growths 
have  not  been  confined  to  the  lower  surface ; in  some,  as  in  Le'pidosteus,  Acipenser, 
and  Holoptychius,  they  have  partially  covered  the  upper  one  also ; whilst  in  others,  as 
in  Lepndotus,  Aspidurhynchus,  &c.,  the  concentric  circle  has  been  made  complete, 
superiorly,  either  by  the  addition  of  continuous  layers  of  true  bone  or  of  ganoin. 
In  either  of  the  latter  cases  the  newly-formed  lamellae  have  completely  enclosed  the 
older  growths ; consequently,  though  agreeing  with  M.  Agassiz  in  the  main,  I can 
scarcely  conclude,  as  he  does,  that  “ I’organe  secreteur  est  la  poche  6pidermoidale 
dans  laquelle  elles  sont  enfoncees  par  leurs  bords  anterieurs.”  It  is  evident  that 
each  scale  must  have  been  completely  and  permanently  surrounded  by  a kind  of 
periosteum,  closely  embracing  its  entire  circumference,  and  prolongations  from  which 
have  entered  many  of  the  Haversian  canals  in  such  genera  as  Megalichthys,  in  the 
opercular  bone  of  Lepidotus,  and  in  Macropoma  Mantelli.  Though  corresponding 
prolongations  may  have  also  entered  the  smaller  parallel  tubes  of  the  Lepidostei  and 
Lepidoti,  we  have  no  evidence  that  these  latter  prolongations  possessed  any  seereting 
power,  since  no  parallel  lamellae  line  their  vertical  walls  ; and  in  the  same  way,  those 
portions  which  have  lined  the  vertical  Haversian  canals  of  Holoptychius  and  the 
trumpet-shaped  cavities  of  Megalichtliys,  do  not  appear  to  have  secreted  any  solid 
tissues.  This  membrane  has  doubtless  derived  its  supplies  of  blood  from  the  soft 
integument,  which  has  not  only  been  in  contact  with  the  whole  base  of  the  scale,  but 
also  with  the  superior  surface  of  its  anterior  and  often  lateral  margin. 

We  also  obtain  from  the  history  of  these  scales,  some  important  evidence  illustrating 
the  process  of  bone-growth  amongst  the  Mammalia.  Most  anatomists  are  aware  that 
some  new  and  highly  interesting  views  have  been  advaneed  by  Prof.  Sharpey,  who 
has  shown  that,  in  the  case  of  each  human  bone,  but  a comparatively  small  portion  of 
it  had  originated  from  the  deposition  of  calcareous  matter  amongst  the  cells  of 
true  cartilage  ; all  its  subsequent  increase  in  thickness  or  diameter  proceeding  from 
the  calcifieation  of  the  inner  layer  of  the  periosteum,  whose  fibres  are  always  found 
to  be  in  intimate  conneetion  with  the  osseous  surface.  According  to  this  view,  the 
Haversian  eanals  have  not  necessarily  originated  in  any  previous  arrangement  of 
the  cartilage  eells,  but  mainly  resulted  from  the  inflexions  of  the  intermembranous 
growths  of  bony  lamellte,  formed  in  the  substance  of  the  periosteum  without  the  in- 
tervention of  any  temporary  eartilaginous  structure:  and  as  an  additional  sequence, 
it  becomes  probable  that  the  lacunae  and  their  canaliculi  had  resulted  neither  from 
a modification  of  the  eartilage  cell,  as  is  believed  by  Schwann  and  Henle,  nor  of  its 
nucleus,  the  view  entertained  by  Mr.  Tomes'!-  ; but  rather  that  they  are  little  vaeuities 

* See  page  437. 


MDCCCXLIX. 


t See  Todd  and  Bowman’s  Physiological  Anatomy,  p.  119. 
3 P 


470  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 

that  have  been  left  out^  during  the  deposition  of  the  membranous  lamellae  and  their 
subsequent  impregnation  with  calcareous  matter*. 

The  appearances  presented  by  the  scales  described  in  the  preceding  pages,  go  far 
to  confirm  these  views.  I have  not  been  able  to  detect  the  slightest  trace  of  cartilage 
cells  in  either  the  recent  scales  of  the  Sturgeon  and  Lepidosteus,  or  in  the  dermal 
teeth  and  plates  of  any  of  the  Piacoid  fish.  The  decalcified  scales  of  the  Sturgeon 
and  Lepidosteus,  show  that  the  lime  is  deposited  in  a granular  form,  in  the  minute 
interstices  of  membranous  lamellte,  and  that,  consequently,  the  origin  of  the  magni- 
ficent lacunas  with  their  largely  developed  canaliculi,  must  be  explained  without 
having  recourse  to  the  intervention  of  cartilage  cells,  either  in  producing  the  cavity 
or  influencing  its  position  in  the  bone. 

In  the  same  way,  the  gradual  progression  to  be  observed  as  we  pass  from  the  simple 
laminated  scale  of  Seminotus  and  Lepidotus,  to  the  complicated  development  of 
Haversian  canals  existing  m Acipenser,  Holoptychius  and  illustrate  how 

the  periosteal  laminae  thickening  the  exterior  of  the  shaft  of  a mammalian  bone,  may 
have  been  twisted  and  inflected;  their  undulations  producing,  first,  grooves  on  its 
surface,  and  subsequently  canals,  from  the  arching  over  of  the  grooves  so  formed, 
by  the  corresponding  but  inversed  inflexions  of  the  more  newly-formed  lamellae : 
whilst  in  some  cases,  as  in  Mepalichthys,  we  find,  what  is  less  evident  in  the  Stur- 
geon, that  after  these  canals  have  been  thus  constructed,  additional  and  more  com- 
pletely concentric  lamellae  have  been  deposited  within  each  canal,  at  once  diminishing 
its  diameter  and  thickening  its  walls. 

We  also  obtain  an  additional  illustration  of  what  the  study  of  comparative  anatomy 
so  frequently  reveals,  viz.  the  unequal  degree  in  which  the  various  portions  of  an 
organized  structure  are  developed,  in  reference  to  the  homological  type  of  each. 
Thus,  whilst  in  Lepidosteus  osseus  we  have  one  of  the  simplest  forms  of  the  laminated 
scale,  associated  with  vertebrae  exhibiting  the  ball-and-socket-joint  of  the  Ophidians, 
and  teeth  approximating  to  a Saurian  form,  in  Megalichthys  and  Holoptychius  we 
have  scales  mainly  consisting  of  a complicated  arrangement  of  Haversian  canals,  and 
abounding  in  long  fusiform  lacunae,  of  the  true  reptilian  type  ; whilst  the  vertebrae  of 
Holoptychius,  certainly,  and  I believe  of  Mepalichthys  also,  present  the  double  con- 
cave articulation  ordinarily  found  in  fishes  and  enaliosaurs. 

The  further  carrying  out  of  this  investigation  into  the  microscopic  structure  of  the 
scales  of  fish,  will  afford  an  important  means  of  distinguishing  different  fossil  species, 
and  also,  when  prudently  employed,  of  establishing  their  affinities  and  alliances;  but 
at  the  same  time  I would  venture  to  caution  the  palaeontologist  against  expecting  too 
much  from  it.  In  many  cases  it  will  enable  us  to  decide  that  two  imperfect  frag- 
ments belong  to  distinct  species,  and  also  to  form  a pretty  correct  judgment  as  to  the 
general  nature  of  each;  but  in  numerous  other  instances,  even  very  different  genera 


* Dr.  Quain’s  Anatomy,  5th  edition,  hy  Dr.  Sharpey  and  Mr.  Quain,  part  2,  p.  cxxxii.  et  seq. 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  471 


of  fish  may  present  but  a small  and  inappreciable  amount  of  difference  in  the  micro- 
scopic structure  of  their  scales  ; thus,  for  example,  a longitudinal  section  of  the  scale 
of  a Gyrodm  exhibits  a much  closer  apparent  analogy  to  that  of  an  Aspidorhynchus 
than  to  that  of  the  more  closely  allied  genus  Platysomus ; though  a close  typical 
resemblance  assimilates  it  to  the  latter.  The  uncertainty  of  this  result  is  also  in- 
creased by  the  various  effects  produced  by  the  mineralization  of  the  fossil  scale.  I 
have  examined  scales  from  some  specimens  of  Lepidotus  semiserratus,  in  which  I 
had  the  greatest  difficulty  in  detecting  traces  either  of  the  beautiful  arborescent  tubuli 
or  of  the  lacunae  shown  in  fig.  4,  they  having  been  almost,  though  not  altogether,  ob- 
literated by  the  process  of  fossilization,  teaching  a lesson  of  caution,  which  the  student 
will  do  well  to  remember.  But  notwithstanding  these  difficulties,  the  value  of  the 
inquiry,  as  furnishing  us  with  an  instrument  which  will  facilitate  the  identification 
of  affinities,  is  considerable,  provided  it  is  not  made  the  sole  standard  of  classification, 
but  employed  in  conjunction  with  an  equally  minute  examination  of  every  other  por- 
tion of  the  animal  organism. 

It  now  only  remains  for  me  to  acknowledge  the  great  kindness  with  which  Sir 
Philip  M.  De  Grey  Egerton,  Bart.,  M.P.,  Dr.  Mantell,  Mr.  Binney,  Mr.  John 
Edward  Gray  and  Mr.  Searles  Wood,  have  afforded  me  every  assistance  in  their 
power,  by  supplying  me  with  many  important  specimens  for  examination  which  my 
own  cabinet  did  not  contain.  To  each  of  these  gentlemen  my  warmest  thanks  are 
due  for  their  most  valuable  cooperation. 


APPENDIX. 

vSince  the  preceding  memoir  was  placed  at  the  disposal  of  the  Royal  Society,  the 
continued  kindness  of  Sir  Philip  Egerton  has  enabled  me  to  examine  specimens  of 
the  curious  premaxillary  bones  of  the  Coelorhynchus,  obtained  both  from  the  London 
clay  and  from  the  tertiary  beds  of  North  America.  They  exhibit  a form  of  kosraine 
which  is  alike  new  and  interesting.  I learn  from  Sir  Philip  Egerton  that  the  rostral 
appendage  of  this  fish  is  made  up  of  two  semi-cylindrical  bones  (see  fig.  35  a a)  in- 
closing a canal,  which  is  double  towards  the  base,  but  which  becomes  coalescent  as 
it  approaches  the  apex,  of  which  latter  portion,  fig.  35  represents  a transverse  sec- 
tion. These  bones  are  marked  externally  with  longitudinal  grooves  and  correspond- 
ing ridges,  the  latter  being  the  external  margins  of  a series  of  long  cuneiform  plates, 
whieh  radiate  from  the  centre  to  the  circumferenee. 

Fig.  36  exhibits  a profile  representation  of  three  of  these  plates,  showing  their  in- 
ternal structure.  Each  plate  is  separated  from  its  neighbour  by  a thin  vertical  net- 
work of  small  canals,  fig.  36  a,  which  open,  externally,  along  the  narrow  groove, 
fig.  36  h,  separating  the  convex  ridges.  In  the  transverse  section,  the  divided  orifices 
of  the  canals  constituting  this  network  are  visible,  fig.  36  c,  along  the  vertical  line  of 
demarcation  between  the  segments.  From  each  side  of  this  line,  vast  numbers  of 

3 p 2 


472  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


minute  kosmine  tubes  are  seen  arching  downwards  and  inwards  towards  the  centre 
of  the  plate,  fig,  36  d.  Similar  tubes  also  descend  from  the  convex  upper  surface  of 
each  plate,  36  e.  From  the  top  to  the  bottom  of  the  segment  are  also  seen  numerous 
arched  lines  of  growth,  which  run  parallel  to  the  upper  surface ; these  are  best  repre- 
sented in  the  segment,  fig.  36 f,  in  which  I have  omitted  the  kosmine  tubes,  in  order 
to  exhibit  the  lamellae  with  more  clearness.  Running  longitudinally  through  the 
centre  of  each  plate  are  several  narrow,  depressed,  semilunar  canals,  fig.  36  g, 
arranged  at  nearly  equal  distances  from  one  another,  and  into  each  of  which  many 
of  the  kosmine  tubes,  coming  both  from  above  and  from  below,  appear  to  open. 

Fig.  37  represents  a horizontal  section  of  two  similar  plates  ; at  37  « we  again  see 
the  orifices  of  the  network  of  canals.  Owing  to  the  arched  direction  assumed  by  the 
kosmine  tubes,  this  section  divides  them  nearly  at  right  angles  at  the  central  part  of 
each  plate,  whilst  it  is  almost  parallel  with  their  plane  at  each  margin ; hence,  at  37  b, 
these  tubes  are  seen  very  distinctly,  whilst  at  37  c rows  of  minute  dots  alone  mark 
the  position  of  their  divided  orifices.  The  latter  do  not  always  run  in  lines  exactly 
parallel  to  the  plane  of  the  marginal  canals,  but  they  exhibit  a strong  tendency  to  do 
so.  Fig.  37  d shows  the  direction  taken  by  one  of  the  semilunar  canals,  fig.  36 g-. 

It  is  very  easy  to  trace  the  process  of  growth  in  this  interesting  structure,  in 
which  each  plate  or  segment  represents  a tooth  turned  inside  out.  The  first  deposi- 
tion of  calcareous  matter  has  been  made  in  the  form  of  a thin  cylinder  surrounding 
the  central  cavity,  fig.  35  h.  New  lamellse,  perforated  with  minute  apertures,  have 
been  formed  upon  this  basis ; the  apertures  in  each  lamella  being  arranged  in  exact 
juxtaposition  with  those  of  the  contiguous  lamellse.  The  minute  tubes  thus  formed 
have  at Jirst  all  opened  at  the  external  surface,  but  it  will  be  readily  seen,  that,  after 
the  addition  of  many  new  lamellse,  owing  to  their  arched  arrangement,  the  tubes  of 
adjoining  plates  would  meet  at  the  line  of  junction,  fig.  36  c,  and  thus  each  segment 
would  contribute  to  block  up  those  of  its  neighbour,  preventing  them  from  receiving 
their  proper  supply  of  nutritious  fluids.  To  obviate  this  difficulty,  however,  the  net- 
work of  minute  canals,  fig.  36  a and  c,  has  been  left  open  between  contiguous  segments. 
The  orifices  of  the  kosmine  tubes  open  into  these  canals,  and  maintain  a free  com- 
munication with  the  surface  through  the  row  of  small  orifices  seen  in  each  superficial 
sulcus,  fig.  36  h.  Thus  the  nutrition  of  the  tissues  in  the  interior  of  each  segment 
continues  to  be  provided  for.  The  use  of  the  longitudinal  canals,  figs.  36  g and  37  d, 
is  uncertain.  They  have  probably  contained  some  form  of  pulpy  matter.  No  trace 
of  true  bone  is  seen  in  the  entire  structure,  which  consists  wholly  of  kosmine.  In  this 
it  bears  a resemblance  to  the  rays  and  dorsal  appendages  of  the  placoid  fish.  The 
kosmine  breaks  with  a translucent  and  shining  fracture. 

It  is  difficult  to  conceive  of  any  arrangement  by  means  of  which  a stronger  fabric 
could  have  been  produced,  than  is  exhibited  in  this  cylindrical  combination  of  long 
radiating  plates.  The  true  nature  of  the  appendage  itself,  as  well  as  that  of  the  fish 
to  which  it  belongs,  is  yet  uncertain ; but  if  it  has  been  a weapon  of  defence,  like  the 


FhiJ,  IrajLsl/^CCCFll'l^.  PI/j]'je.Y\U.-p  4j5. 


Fi^  1. 


■ del. 


J.Basirt  luhey 


m/.  s. 

7) 


■J.  JS’.'A'VV  ■■' 


1 


SCALES  AND  DERMAL  TEETH  OF  SOME  GANOID  AND  PLACOID  FISH.  473 


snout  of  the  recent  Sword-fish,  the  creature  must  have  proved,  in  no  small  degree, 
formidable  to  its  congeners. 

In  all  its  details,  the  structure  corroborates  the  conclusion  arrived  at  in  the  pre- 
ceding memoir,  and  shows  not  only  a process  of  growth  by  the  addition  of  lamellae, 
similar  to  that  already  described,  but  also  indicates  further,  that  whatever  may  be 
the  direction  and  distribution  either  of  kosmine  or  lepidine  tubes,  the  additions  to 
the  structure  which  they  permeate  are  always  made  to  the  surface  on  which  their 
largest  apertures  open ; whether  that  surface  be  found  in  an  internal  cavity,  as  in 
Megalichthys  and  Diplopteriis,  or  whether  it  is  in  their  exterior,  as  in  Ccelorhynchus. 


Description  of  the  Plates. 

PLATE  XL. 

Fig.  1.  Vertical  section  of  a scale  of  Lepidosteus  osseus,  parallel  with  the  lateral  line 
of  the  fish.  Magnified  8 diameters. 

Fig.  2.  Vertical  section  of  the  half  of  a similar  scale,  made  at  right  angles  to  the 
lateral  line.  Magnified  14  diameters. 

Fig.  3.  Vertical  section  of  the  anterior  border  of  a scale  of  Lepidotus  semiserratus, 
parallel  with  the  lateral  line.  Magnified  25  diameters. 

Fig.  4.  Horizontal  section  of  the  upper  surface  of  part  of  the  same  scale.  Mag- 
nified 112  diameters. 

Fig.  5.  Horizontal  section  of  a tubercle  from  the  surface  of  a scale  of  Dapidius 
granulosus. 

Fig.  6.  Vertical  section  of  the  same. 

Fig.  7-  Horizontal  section  of  part  of  the  surface  of  Palceoniscus  comptus.  Mag- 
nified 90  diameters. 


PLATE  XLI. 

Fig.  8.  Horizontal  section  of  part  of  the  surface  of  Palceoniscus  Beaumontii. 

Fig.  9.  Vertical  section  of  a scale  of  Seminotus  rhombifer,  made  parallel  to  the  lateral 
line. 

Fig.  9*.  Vertical  section  of  a scale  of  a Gyrodus  from  Kellheim,  parallel  to  the  lateral 
line. 

Fig.  10.  Vertical  section  of  Aspidorhynclius  acutirostris,  parallel  to  the  lateral  line. 
Magnified  16  diameters. 

Fig.  11.  Vertical  section  of  part  of  a scale  of  Acipenser  Sturio,  parallel  with  the  lateral 
line  of  the  fish,  and  midway  between  the  centre  and  the  lower  angle  of 
the  lozenge-shaped  scale.  Magnified  7 diameters. 

Fig.  12.  Vertical  section  of  a scale  of  Platysomus  parvulus,  parallel  with  the  lateral 
line.  Magnified  80  diameters. 


474  MR.  W.  C.  WILLIAMSON  ON  THE  MICROSCOPIC  STRUCTURE  OF  THE 


Fig-.  13.  Vertical  section  of  the  upper  half  of  the  same  scale,  made  at  right  angles  to 
the  lateral  line.  Magnified  100  diameters. 

Fig.  14.  Horizontal  section  of  part  of  the  same  scale,  made  in  the  direction  of  the 
line,  fig.  1'2  ef. 

Fig.  15.  Vertical  section  of  part  of  a scale  of  Megalichthys  Hihhertii.  Magnified 
80  diameters. 

PLATE  XLIL 

Fig.  16.  Horizontal  section  of  part  of  the  surface  of  the  scale  of  Megalichthys  Hib- 
heriii.  Magnified  60  diameters. 

Fig.  17.  Vertical  section  of  part  of  a scale  of  a small  species  of  Megalichthys. 
Magnified  110  diameters. 

Fig.  18.  Vertical  section  of  the  lower  part  of  a scale  of  Megalichthys  Hibhertii,  made 
at  right  angles  to  the  lateral  line!  Magnified  10  diameters. 

Fig.  19.  Horizontal  section  of  the  laminae,  fig.  15  i,  Megalichthys  Hibbertii.  Mag- 
nified 300  diameters. 

Fig.  20.  Oblique  horizontal  section  of  the  upper  part  of  a Diplopterus.  Magnified 
27  diameters. 

Fig.  21.  Upper  surface  of  a large  scale  of  Holopty chins  sauroides,  natural  size. 

Fig.  22.  Inferior  surface  of  the  same  scale. 

Fig.  23.  Vertical  section  of  a scale  of  Holopty  chins  sanroides,  taken  in  the  direction 
of  the  dotted  line,  fig.  22  c.  Magnified  30  diameters. 

Fig.  24.  Vertical  section  of  part  of  the  scale  of  a species  of  Holoptychius,  made  nearly 
in  the  direction  of  the  line,  fig.  22  c,  only  verging  more  towards  the  centre 
of  the  scale.  Magnified  30  diameters. 

Fig.  25.  Horizontal  section  of  the  surface  of  the  opercular  bone  of  Macropoma  Man- 
telli.  Magnified  25  diameters. 

Fig.  26.  Vertical  section  of  part  of  the  same  opercular  bone,  taken  parallel  to  the 
lateral  line  of  the  fish.  Magnified  70  diameters. 


PLATE  XLIII. 

Fig.  27.  Vertical  section  of  parts  of  two  scales  of  Macropoma  Mantelli,  made  parallel 
to  the  mesial  line.  Magnified  25  diameters. 

Fig.  28.  Vertical  section  of  a row  of  large  dermal  teeth,  from  the  centre  of  a scale  of 
Macropoma  Mantelli.  Magnified  18  diameters. 

Fig.  29.  Horizontal  section  of  the  surface  of  the  internal  osseous  viscus  of  Macro- 
poma Mantelli.  Magnified  350  diameters. 

Fig.  30.  Vertical  section  of  the  parietes  of  the  same  viscus,  taken  in  the  direction  of 
its  long  axis,  and  parallel  to  the  mesial  line.  Magnified  350  diameters. 


r/-w(.^  7'rcuis  m')ZZZl\,\\J'La.lel\\\:pu7J<.. 


■7/®, 


1 


Phii.Tran£. 


fKr 


/'Tlas 


SCALES  AND  DERMAL  TEETH  OF  SOxME  GANOID  AND  PLACOID  FISH.  475 


Fig-.  31.  Horizontal  section  of  the  shagreen  of  the  common  Dog-fish,  the  bases  and 
apices  of  the  dermal  teeth  being  alike  ground  away.  The  faint  ring 
surrounding  each  areola  is  produced  by  the  form  of  the  tooth ; the  upper 
section  having  divided  it  at  a narrower  point  than  the  lower  one,  thus 
shows  a portion  of  the  surface  of  each. 

Fig.  32.  Vertical  section  of  one  of  the  dermal  teeth  of  fig.  31. 

Fig.  33.  Vertical  section  of  the  fossil  shagreen  of  the  Hybodus  reticulatus. 

Fig.  34.  Vertical  section  of  the  surface  of  the  snout  of  the  common  Saw-fish  {Prdstls). 
Magnified  65  diameters. 

Fig.  35.  Vertical  section  of  the  premaxillary  bones  of  a Coelorhynchus.  Natural  size. 

Fig.  36.  Profile  view  of  part  of  the  same  organism.  Magnified  6 diameters. 

Fig.  37.  Horizontal  section  of  portions  of  two  segments  of  the  same.  Magnified 
9 diameters. 


?y'f 


v;:'  ■ ^ 


. • ■ ■ V,  ••  , 


■ ^ V. 


'I  :'i  ,:;  ivVlifTsf 


ir  i v>,>  ^ r>.i,,;ji':^ 


) :.'’■  -I  '■  ’/<■ 

!tO<)  H:  -».>! 


H 


• ■ ■,  ^ . ;7  ■;,  <, -r  ■ y;;,  ^ '■' -'H  ■''' 


;:’a 

i 


'''^o  ■ ^ ';'^1 


■ 7 . " .K, 


'>■ 

" ■'  1'  '':W  si; 


7'  ■ ' ; ' ■ +.  ^'^ 


.I'M'K:  'It,  -.' 

^mi-  .:  i 


■•5"-  '''>’:iS^  ■ '■'-‘V  li  • .Mi 


.■,;W:...- 

Vf-'"'  V . 


V7%.‘ 


■V.;'  >.  ■<*:>  : ' ' 


:'  'A  '■  ■ 


l<'-  '!■,  * 4'iv.'' 

v ,'  , ;■, 


VI;-  '.-  ''  ,,!.:  ■-.  ■ ■: ' '■'  ■ 

'■  ■ ' ''■' ^V'. ' / -i.  i ' ^ ''  -'w'"  ■''®  '^v'4  7'|.'  ,;•  'vVt'y'xi^^ 

. ■ ■^'^■•^^■■  - ■'  a/'H 


=i!  ;.  >'';. 


‘.SaI 


’■  i#  'V- 


',  ■;  ■ lyyX^ 


[ 477  ] 


XXIV.  On  the  Nitroprussides,  a New  Class  of  Salts. 
By  Dr.  Lyon  Playfair,  F.R.S.,  F.C.S. 


Received  June  21, — Read  June  21,  1849. 


1.  In  an  inquiry  into  the  constitution  of  the  prussides,  1 found  it  necessary  to 
examine  into  the  somewhat  anomalous  action  of  nitric  acid  on  the  yellow  prusside  of 
potassium.  This  examination  has  led  to  the  discovery  of  a singular  class  of  com- 
pounds, which  form  the  subject  of  the  present  memoir. 

The  previous  knowledge  on  the  action  of  nitric  acid  on  the  prussides  may  be 
summed  up  very  briefly.  Thomson*  examined  the  gases  produced  during  the  action, 
and  recognized  them  to  be  nitrogen,  cyanogen,  nitric  oxide,  and  carbonic  acid,  while 
the  residue  was  believed  to  consist  of  pernitrate  of  iron  and  nitrate  of  potash. 
DoBEREiNER'f'  remarked  that  previous  to  the  complete  decomposition  of  the  prus- 
sides, a strong  coffee-coloured  liquid  was  produced,  which,  after  neutralization, 
precipitated  protosalts  of  iron  of  a dark  blue  colour.  Gmelin:{;,  to  whom  chemistry 
was  already  indebted  for  important  discoveries  in  the  prussides,  observed  that  the 
coffee-coloured  liquid  noticed  by  Dobereiner  was  rendered  of  a magnificent  purple 
or  blue  colour  on  the  addition  of  an  alkaline  sulphide.  The  same  fact  was  noted  by 
Mr.  Mercer  § of  Oakenshaw,  without  his  being  aware  that  it  had  already  been  re- 
marked by  Gmelin.  Campbell II,  in  repeating  Gmelin’s  experiment,  threw  out  the 
intelligent  suggestion  that  the  purple  colour  might  be  due  to  the  production  of  a 
sulphuret  of  nitrogen,  which  Gregory^  had  already  remarked  produced  an  ame- 
thystine colour  when  mixed  with  an  alcoholic  solution  of  potash.  Smee**,  in  an 
examination  of  the  action  of  nitric  acid  on  the  prussides,  observes  that  ferridcyanide 
is  produced,  nitric  oxide  being  evolved. 

I am  not  aware  of  any  further  knowledge  on  this  subject ; and  as  it  is  far  from 
being  sufficiently  extended,  a new  examination  was  desirable. 

2.  When  dissolved  ferrocyanide  of  potassium  is  digested  with  diluted  nitric  acid,  a 
coffee-coloured  liquid  is  produced,  having  the  characters  ascribed  to  it  by  Dobereiner 
and  Gmelin.  The  addition  of  this  acid  solution  to  sulphide  of  potassium  dissolved 
in  water  causes  a precipitation  of  sulphur  and  the  production  of  various  colours,  from 
a pink  to  a violet  or  blue  shade.  When  the  acid  liquid  is  neutralized  with  potash,  it 

* As  quoted  by  Gmelin,  Handbuch,  Band  iv.  s.  370.  f Schw.  J.  xxvi.  p.  305. 

t Ann.  Pharm.  Bd.  xxviii.  s.  57,  and  Memoirs  of  Chem.  Soc.  vol.  i.  p.  41. 

§ Unpublished  Letter.  ||  Handbuch,  B.  i.  s.  167. 

^ Turnee’s  Chemistry,  p.  343.  **  Mag.  xvii.  194. 

3 Q 


MDCCCXLIX. 


478 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


immediately  produces  the  most  intense  purple  coloration  with  a soluble  sulphide*. 
The  action  of  nitric  acid  on  the  pounded  salt  is  similar,  but  much  more  violent  than 
that  experienced  with  the  solution.  Nitric  oxide  is  at  first  evolved,  but  it  soon  ceases 
if  the  mixture  be  kept  cool,  and  it  is  followed  by  the  copious  escape  of  cyanogen  gas, 
accompanied  by  hydrocyanic  acid,  and  a gas  of  peculiar  pungency,  apparently 
hydrated  cyanic  acid  ; more  or  less  nitrogen  and  carbonic  acid  are  also  found  in  the 
escaping  gases.  The  dark  red  solution  remaining  after  the  action,  deposits,  on 
cooling,  abundance  of  nitrate  of  potash,  and,  under  the  most  favourable  circumstances, 
about  5 per  cent,  of  a peculiar  white  substance,  afterwards  to  be  described.  The 
red-coloured  solution  now  precipitates  protosalts  of  iron  of  a dark  blue  colour,  or  if 
it  has  been  heated  for  a short  time,  or  even  stood  in  the  cold  for  some  days,  of  a dark 
green,  and  sometimes  of  a slate  colour.  A dark  green  precipitate  is  also  produced 
on  the  addition  of  salts  of  copper.  The  same  precipitates  are  obtained  from  the 
neutralized  as  from  the  acid  solution.  Such  were  the  preliminary  observations  made 
on  repeating  Dobereiner’s  experiment. 

One  important  fact  was  observed  in  this  preliminary  trial,  viz.  that  nitric  oxide 
disappeared  during  the  action,  and  in  fact  only  occurred  when  the  transformation 
was  so  violent  as  to  escape  control.  This  gas  was  therefore  probably  one  important 
cause  of  the  change,  and  it  therefore  became  necessary  to  examine  its  action  on  the 
cyanides,  as  a more  simple  means  of  eliciting  its  mode  of  action. 

3.  The  first  obvious  experiment  was  to  ascertain  whether  cyanide  of  potassium 
charged  with  nitric  oxide  would  produce  prussides  exerting  the  remarkable  colouring 
action  on  the  sulphides.  Nitric  oxide  is  in  fact  readily  absorbed  by  cyanide  of  potas- 
sium, the  solution  becoming  red-coloured  and  depositing  a black  substance  resem- 
bling paracyanogen.  This  red-coloured  solution  did  not  of  itself  give  any  colour 
when  mixed  with  a sulphide.  It  was  now  converted  into  a prusside  by  the  addition 
of  protosulphate  of  iron.  The  resulting  prusside  was  now  found  to  strike  a magnifi- 
cent purple  colour  with  a soluble  sulphide.  The  same  coloration  was  obtained  when 
a prusside  was  made  from  common  cyanide  of  potassium  added  to  a solution  of  pro- 
tosulphate of  iron,  through  which  nitric  oxide  had  been  passed.  It  was  obvious  from 
these  experiments  that  nitric  oxide  was  one  of  the  great  causes  of  the  change  experi- 
enced by  the  prusside. 

4.  The  action  of  nitric  oxide  on  the  prussides  themselves  was  now  examined.  It 
was  found  that  nitric  oxide  could  be  passed  through  a solution  of  ferrocyanide  of 
potassium  without  producing  any  sensible  change.  But  when  the  prusside  was  mixed 
with  sufficient  acid  to  take  up  its  alkaline  base,  it  was  now  found  that  nitric  oxide 
was  freely  absorbed  by  this  mixture  when  heated,  though  not  in  the  cold  ; and  that 


* The  intensity  and  beauty  of  this  coloration  render  the  nitroprussides  the  most  sensible  of  all  tests  for  the 
presence  of  the  minutest  trace  of  a soluble  sulphide.  The  presence  of  quantities  insensible  to  ordinary  tests  is 
at  once  strongly  exhibited  by  the  use  of  this  colouring  agent. 


A NEW  CLASS  OF  SALTS. 


479 


the  resulting  liquid  exhibited  the  strong  coloration  with  sulphides.  Ferrocyanide  of 
lead,  or  any  other  ferrocyanide,  gave,  when  mixed  with  strong  acids,  a similar  result. 
It  was  therefore  obvious  that  the  peculiar  compound  might  be  obtained  from  pure 
hydroferrocyanic  acid.  The  latter  acid  was  prepared  from  prusside  of  lead  by  sul- 
phuretted hydrogen,  the  excess  of  the  latter  being  removed  by  the  addition  of  a little 
more  lead  salt.  The  filtered  ferrocyanic  acid  was  found  to  suffer  no  change  when 
exposed  to  the  action  of  nitric  oxide  in  the  cold  ; but  when  the  solution  was  kept  in 
a water-bath  and  the  gas  led  through  it,  a change  was  observed.  This,  however,  at 
first  merely  consisted  in  the  transformation  of  ferrocyanic  to  ferridcyanic  acid, — 

4(Fe  Cy3+2H) +N02=2 (Fe2  Cyg+3H)-l-2HO-f  N. 

Until  this  change  was  completed  not  the  least  coloration  took  place  on  mixing  the 
acid  liquid  with  a sulphide.  When,  however,  the  acid  no  longer  gave  prussian  blue 
with  perchloride  of  iron,  it  began  to  assume  a red  colour,  continuing  to  evolve  a gas, 
and  it  now  exhibited,  after  neutralization,  the  peculiar  coloration  with  sulphides.  It 
nov/  gave  a blue  precipitate  with  protosulphate  of  iron,  like  ordinary  ferridcyanic  acid. 
This  blue  precipitate  became  paler  in  colour  as  the  gas  continued  to  stream  through 
the  hot  solution,  until  finally  the  addition  of  the  iron  salt  gave  a precipitate  of  a clear 
salmon  colour.  Here  then  was  the  acid*  of  the  new  compounds,  and  its  salts  were 
obtained  by  neutralization  with  the  respective  bases.  This  process  was  a great  step 
in  the  inquiry,  because  it  enabled  the  distinctive  characters  of  the  nitroprussides  to 
be  determined.  At  the  same  time  it  was  not  fitted  to  procure  the  salts  in  sufficiently 
large  quantities  for  examination.  By  showing  however  what  was  to  be  looked  for,  it 
enabled  a more  complete  examination  to  be  made  of  the  products  of  oxidation  of  the 
prussides  by  nitric  acid,  with  a view  to  the  separation  of  the  nitroprussides  from 
the  ferridcyanides,  with  which  they  were  obviously  mixed. 

5.  It  was  observed  that  the  oxidized  prusside  required  a very  small  quantity  of 
protosulphate  of  iron  for  its  complete  precipitation.  One  double  equivalent  of  ferro- 
cyanide of  potassium  (Fe2Cye+4K)  was  oxidized  with  3 equivs.  of  nitric  acid  diluted 
with  its  own  volume  of  water.  The  dark  red,  almost  black  liquid,  was  diluted  with 
water  and  treated  with  a known  quantity  of  sulphate  of  iron  dissolved  in  water. 
Prussian  blue  was  formed,  but  it  remained  in  solution,  forming  a dark  blue  soluble 
fluid,  of  great  beauty  and  intensity.  When  the  added  sulphate  of  iron  amounted  to 
one  equivalent,  that  is  to  one-fourth  of  the  potassium  originally  in  the  prusside,  the 
Prussian  blue  became  insoluble  and  was  thrown  on  a filter  and  washed.  It  was 
obvious  from  this  experiment  that  there  must  be  a potassium  salt  in  combination 
with  the  Prussian  blue,  because  the  quantity  of  iron  salt  added  was  quite  insufficient 
to  unite  with  the  iron  and  cyanogen  of  the  radical.  This  idea  was  confirmed  by 

* On  neutralizing  this  nitroprussic  acid  with  carbonates,  the  resulting  salts  were  found  to  be  accompanied 
by  a nitrate,  although  the  nitric  oxide  had  previously  been  passed  through  water  in  a washing-bottle. 

3 Q 2 


480 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


finding  that  2 equivs.  of  sulphate  of  copper  were  required  to  effect  the  precipitation, 
which  1 equiv.  of  sulphate  of  iron  had  effectually  done.  To  separate  the  potassium 
salt  present  in  the  latter  case,  the  precipitated  prussian  blue,  after  being  washed 
with  cold  water,  was  mixed  with  water  and  boiled.  The  whole  was  now  thrown 
on  a filter,  and  a solution  of  a fine  ruby-red  colour  passed  through.  This  solution 
gave  a salmon-coloured  precipitate  with  a protosalt  of  iron.  This  precipitate  does 
not  readily  occur  in  an  acid  liquid,  and  hence  the  addition  of  the  iron  salt  to  the 
original  oxidized  solution  does  not  effect  a complete  precipitation,  the  filtrate  from  it 
being  yellow  from  dissolved  nitroprusside  of  iron.  There  being  always  some  nitro- 
prusside  of  iron  along  with  the  prussian  blue,  the  simple  treatment  with  hot  water 
does  not  wholly  economise  the  products,  as  it  only  separates  the  salt  of  potassium. 
The  mixture  may  therefore  be  decomposed  by  caustic  potash,  which,  added  in  suffi- 
cient quantity,  forms  peroxide  of  iron,  and  ferrocyanide  instead  of  ferridcyanide, — 

(Fe2  Cy0-}-3K.)-J-K.O-{-2FeO=2(Fe  Cy3-)-2K.)-f-Fe2  O3. 

The  ferrocyanide  may  now  be  separated  from  the  nitroprusside,  either  by  precipita- 
tion by  alcohol,  or  by  the  addition  of  nitrate  of  lead.  These  plans  were  not  however 
so  advantageous  as  the  simple  means  of  separation  given  above.  That  method  was 
followed  for  some  time  until  the  examination  of  the  nitroprussides  threw  some  light 
on  their  properties  and  composition  ; it  was  then  found  that  a process  yielding  a 
much  larger  product  of  the  new  compound,  might  be  invented.  The  following  study 
was  therefore  made  of  the  products  arising  from  the  oxidation  of  the  prussides  by 
nitric  acid.  The  knowledge  thus  obtained  led,  as  was  expected,  to  a very  economical 
and  simple  means  of  obtaining  the  nitroprussides  in  large  quantities. 

6.  As  nitric  oxide  was  one  of  the  most  important  means  of  producing  the  conver- 
sion of  prussides  into  nitroprussides,  it  was  necessary  to  operate  so  as  to  prevent  its 
escape.  This  was  done  by  keeping  the  mixture  of  acid  and  prusside  well-cooled  at 
the  first  part  of  the  action.  Nitric  oxide  is  almost  always  evolved  at  first,  but  it 
soon  diminishes  to  nothing  as  the  action  proceeds.  A copious  evolution  of  gas  takes 
place.  The  escaping  gas  burns  with  the  characteristic  purple  flame  of  cyanogen. 
Led  through  protosulphate  of  iron,  after  the  first  violent  action  has  ceased,  no  black- 
ening is  perceived,  so  that  nitric  oxide  has  ceased  to  be  evolved.  Led  into  caustic 
barytes,  carbonate  of  barytes  is  precipitated,  and  the  solution  is  found  to  contain 
cyanide  of  barium  and  cyanate  of  barytes.  When  the  gas  is  collected  ovei‘  mercury 
and  potash  is  thrown  into  the  tube  containing  it,  a portion  of  gas  still  remains  un- 
absorbed and  is  easily  recognized  as  nitrogen.  When  the  escaping  gas  is  led  into 
water  it  is  dissolved  in  considerable  quantity,  and  the  water  now  smells  strongly  of 
cyanogen  and  of  a peculiar  pungent  gas,  which  appears  to  be  hydrated  cyanic  acid. 
The  gas  treated  with  ammonia  deposits  azulmic  acid,  and  the  usual  products  of  the 
transformation  of  cyanogen.  The  following  process  is  found  best  adapted  for  the 


A NEW  CLASS  OF  SALTS. 


481 


preparation  of  the  nitroprusside.  Nitric  acid  of  commerce  is  diluted  with  its  own 
bulk  of  water,  and  the  quantity  of  it  necessary  to  neutralize  53‘3  grs.  of  carbonate 
of  soda  (1  equiv.)  is  ascertained  by  the  alkalimeter.  This  quantity  denotes  1 equiv. 
of  acid. 

Ferrocyanide  of  potassium  is  now  reduced  to  powder  and  is  placed  in  a convenient 
vessel,  and  for  every  422  grs.  of  the  salt  used  (that  is  for  1 equiv.  Fcg  Cyg  4K+6HO) 
5 equivs.  of  the  acid  are  employed.  This  quantity  of  acid  is  found  to  produce  an 
economical  result,  but  it  is  very  remarkable  that  one-fifth  of  the  quantity,  or  1 equiv.,  is 
sufficient  to  convert  a large  portion  of  the  prusside  into  nitroprusside.  This  is  the  more 
remarkable,  because  there  are  four  available  equivalents  of  potassium,  and  it  was  to  be 
expected  that  nitrate  of  potash  would  be  produced.  This  however  is  not  the  case, 
1 equiv.  of  nitric  acid  effecting  oxidation  to  a considerable  extent  on  a double  equivalent 
of  yellow  prusside.  The  five  equivalents  of  acid  mentioned  above  are  at  once  poured 
on  the  prusside,  as  the  cooling  effect  of  the  whole  reduces  the  violence  of  the  action. 
The  mixture  assumes  a milky  appearance,  but  soon  the  salt  dissolves  with  a brownish- 
red  colour  like  coffee,  the  mixture  of  gases  already  described  being  freely  evolved. 
When  the  solution  is  complete,  it  is  found  to  contain  ferridcyanide  of  potassium  mixed 
with  a nitroprusside  and  nitrate  of  potash.  It  is  now  removed  into  a bolt-head  and 
digested  in  the  water-bath.  It  continues  to  evolve  gas,  and  after  a time  it  no  longer 
yields  prussian  blue  with  sulphate  of  iron,  but  forms  a dark  green  or  a slate-coloured 
precipitate.  The  solution  is  now  removed  from  the  water-bath  and  is  allowed  to  cool, 
during  which  abundance  of  nitrate  of  potash  crystallizes  out,  and  always  more  or 
less  of  a peculiar  white  substance.  The  dark  coffee-coloured  mother-liquor  is  now- 
neutralized  with  carbonate  of  soda  or  carbonate  of  potash,  according  as  salts  of 
sodium  or  potassium  are  desired.  The  neutralized  solution  shows  the  presence  of  iron 
existing  as  a base,  for  prussian  blue  is  precipitated  on  the  addition  of  a prusside.  The 
neutral  solution  is  now  boiled,  and  it  deposits  generally  a green  precipitate,  though 
occasionally  one  of  a brown  colour ; and  the  filtrate  is  found  to  be  of  a dark  ruby-red, 
containing  only  nitroprusside  of  the  base  employed  and  a nitrate.  The  latter  is 
separated  by  crystallization  in  the  manner  pointed  out  under  the  respective  salts. 
Nitroprusside  of  sodium  being  most  easily  prepared,  is  recommended  as  the  product 
of  the  process  here  given. 

Some  practical  difficulties  may  be  mentioned  so  as  to  prevent  disappointment  in 
the  preparation.  A carbonate  of  and  not  the  caustic  alkali  should  be  employed  in 
the  neutralization.  When  the  latter  is  used,  the  solution  of  nitroprusside  is  apt  to 
be  mixed  with  ferrocyanide.  When  this  takes  place  an  addition  of  acid  serves  to 
remove  the  impurity,  as  some  of  the  precipitated  oxide  of  iron  is  dissolved,  and  form- 
ing prussian  blue  with  the  ferrocyanide,  removes  it  from  the  solution.  This  impurity 
may  also  be  removed  by  the  addition  of  nitrate  of  lead,  which  precipitates  the  prus- 
side but  not  the  nitroprusside ; or  it  may  be  taken  away  by  the  gradual  addition  of 


482 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


sulphate  of  iron,  which  removes  the  ferrocyanide  before  precipitating  the  nitroprusside* 
When  the  quantity  last  added  precipitates  the  solution  of  a salmon  colour,  the  impu- 
rity has  been  removed*. 

Red  prusside  (ferridcyanide)  of  potassium  may  be  used  in  the  preparation  exactly 
as  described  for  the  yellow  prusside. 

7.  The  following  experiments  were  made  in  order  to  ascertain  approximatively  how 
much  nitroprusside  was  formed  by  the  process  now  described.  105'5  grs.  crystallized 
ferrocyanide  of  potassium  were  digested  with  1^  equiv.  of  nitric  acid.  After  diges- 
tion the  liquid  was  neutralized  with  carbonate  of  soda  and  boiled,  the  resulting  green 
precipitate  being  collected  on  a weighed  filter.  The  filtrate  was  precipitated  by  a salt 
of  copper,  and  the  nitroprusside  of  copper  was  collected  and  weighed. 

It  was  found  by  various  trials  that  perfectly  uniform  results  could  not  be  obtained, 
the  amount  and  even  the  composition  of  the  precipitate-^  on  boiling  varying  with  the 
conditions  of  the  preparation.  The  two  following  experiments  may  be  taken  as 
giving  mean  results  : — 

I.  105’5grs.  yellow  prusside  gave  8’275  green  precipitate,  yielding  on  incineration 
7*95  grs.  peroxide  of  iron  ; the  filtrate  gave  48‘90  grs.  nitroprusside  of  copper. 

II.  105’5grs.  yellow  prusside  gave  8'32grs.  green  precipitate,  yielding  by  calcula- 
tion 6'30grs.  peroxide  of  iron  ; the  filtrate  gave  46‘12  grs.  nitroprusside  of  copper. 

Taking  the  mean  of  the  two  experiments,  105'5grs.,  or  one-fourth  of  the  double 
equivalent  of  yellow  prusside,  yield  8‘297  grs.  green  precipitate  containing  4'984  grs. 
iron;  the  filtrate  yields 47‘51  grs.  nitroprusside  of  copper.  But  before  drawing  de- 
ductions, it  is  necessary  to  know  the  composition  of  the  green  precipitate.  It  con- 
sists of  a mixture  of  prussian  blue,  nitroprusside  and  peroxide  of  iron,  this  mixture 
not  being  constant.  However,  to  take  a special  case  as  an  example, — 

22‘26grs.,  calcined  and  treated  with  nitrate  of  ammonia,  gave  13*62  grs.  peroxide 
of  iron,  or  42*83  per  cent,  of  metallic  iron. 

9*49  grs.  burned  with  oxide  of  copper,  gave  4*13  grs.  carbonic  acid  and  0*96  gr. 
water;  the  carbon  is  therefore  11*87  per  cent.,  the  water  10*11. 

35*02  grs.  treated  by  caustic  potash,  gave,  when  neutralized  by  acetic  acid,  a red 

* It  is  perhaps  needless  to  remark,  that  when  the  ruhy-red  solution  free  from  prussides  has  been  obtained  by 
any  of  the  processes  above  described,  it  may  be  used  at  once  for  the  precipitation  of  the  insoluble  nitro- 
prussides. 

t The  composition  of  the  precipitates  varies  considerably.  If  on  neutralizing  the  acid  solution  an  excess  of 
alkali  be  added,  the  addition  of  an  acid  gives  a slaty  precipitate,  which  consists  mainly  of  oxide  of  iron  mixed 
with  Prussian  blue.  Under  somewhat  similar  conditions,  I believe,  though  on  this  subject  I am  not  certain, 
the  precipitate  on  boiling,  instead  of  being  green,  is  brown,  like  oxide  of  iron.  On  washing  and  exposure  to 
the  air  it  becomes  green. 

In  an  experiment  where  this  precipitate  came,  105'5  grs.  yellow  prusside  gave  5'83  grs.  of  a brown  precipi- 
tate, and  50' 66  grs.  of  nitroprusside  of  copper.  In  another  experiment  with  a like  quantity,  4*755  grs.  of  the 
brown  precipitate  were  obtained. 


A NEW  CLASS  OF  SALTS. 


483 


filtrate,  from  which  the  ferrocyanide  of  potassium  was  precipitated  by  alcohol ; the 
filtrate  from  this  had  all  the  properties  of  nitroprusside  of  potassium,  and  gave  by 
precipitation  with  sulphate  of  copper  13'98  grs.  nitroprusside  of  copper,  equal  to 
13'24  grs.  nitroprusside  of  iron,  or  37’80  per  cent. 

The  reactions  in  the  preparation  of  the  nitroprusside  may  now  be  approximatively 
explained. 

By  reference  to  the  ascertained  composition  of  the  nitroprussides,  it  will  be  seen 
that  the  47*51  grs.  of  the  copper  nitroprusside  obtained  from  the  105*5  grs.  of  yellow 
prusside,  are  equal  to  35*69  grs.  anhydrous  nitropriissic  acid  : this  quantity  contains 
9*66  grs.  of  iron.  Now  14  grs.  iron  were  present  in  the  yellow  prusside  used,  so  that 
about  two-thirds  of  the  iron  have  been  converted  into  nitroprussic  acid.  The  other 
third  is  in  the  green  precipitate,  which  was  found  to  contain  4*98  iron ; if  it  had 
been  one-third  it  should  have  been  4*66;  of  this  quantity  1*19  is  as  nitroprusside  of 
iron,  and  therefore  0*59  as  nitroprussic  acid.  Hence  we  have  out  of  the  14  grs.  iron 
present  in  the  ferrocyanide  10*25  grs.  converted  into  nitroprussic  acid,  or  very 
nearly  three-fourths  ; the  remaining  one-fourth  is  partly  as  prussian  blue  and  oxide  of 
iron,  and  partly  as  the  basic  iron  in  the  nitroprusside  of  iron. 

The  quantity  of  carbon  or  of  cyanogen  converted  into  nitroprusside  has  now  to  be 
examined.  The  47*5 1 grs.  copper  nitroprusside  contain  9*93  grs.  of  carbon,  that  in  the 
nitroprusside  of  iron  of  the  green  precipitate  would  amount  to  0*60,  hence  the  carbon 
converted  into  nitroprussic  acid  is  10*53.  There  were  3 equivs.  or  18  grs.  of  carbon 
in  the  yellow  prusside,  of  which  about  If  equiv.  has  been  converted  into  nitroprus- 
side; of  the  remaining  7^  grs.  carbon  or  16*2  grs.  cyanogen,  about  0*38  gr.  carbon 
or  0*823  gr.  cyanogen  remain  in  the  green  precipitate  as  a cyanide,  the  remainder 
escaping  as  a gas.  It  is  true  that  the  results  here  given  only  form  a rude  approxima- 
tion, but  they  denote  sufficiently  the  final,  though  not  all  the  intermediate  changes 
which  occur ; the  ultimate  action  may  be  expressed  by  the  following  equation : — 

8(FeCy3-l-2K)-|-19(HO,  N05)  = 16(K0,N05)-f-(Fe5 Cyi2  3NO+5H) 

-|-Fe  Cy-f-Fcg  O3-I-2H  Cy-}-9Cy-|-  12HO. 

Thus  8 equivs.  ferrocyanide  of  potassium  lose  their  potash  by  16  equivs.  of  nitric 
acid,  and  the  hydroferrocyanic  acid  formed  is  oxidized  at  the  expense  of  3 equivs. 
nitric  acid,  the  3 equivs.  of  nitrous  oxide  thus  formed  entering  into  the  constitution 
of  nitroprussic  acid,  12  equivs.  of  water  being  formed  by  the  oxidation.  Of  the  cva- 
nogen,  12  equivs.  remain  in  the  nitroprussic  acid,  2 equivs.  escape  as  hydrocyanic 
acid,  9 e(ijuivs.  as  cyanogen,  and  1 equiv.  remains  united  with  iron  as  a cyanide.  This 
scheme  would  require  10*04  grs.  of  the  iron  experimented  on  to  be  converted  into 
nitroprussic  acid,  and  direct  experiment  gave  10*2  grs.  We  should  indeed  find 
1*8  gr.  cyanogen  in  the  cyanide  of  iron*,  whereas  only  0 823  gr.  cyanogen  was  found 

* The  empirical  formula  Fe  Cy  represents  the  actual  proportion  of  iron  and  cyanogen  in  certain  prussian  blues, 
although  the  elements  are  not  arranged  according  to  this  simple  expression. 


484 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


in  this  state ; but  when  we  consider  the  small  quantity  present  and  the  variable  nature 
of  Prussian  blues,  such  a discordance  is  not  fatal  to  the  correctness  of  an  explanation, 
which  is  only  given  as  an  approximation. 

8.  It  has  already  been  mentioned  that  carbonic  acid  was  one  of  the  products 
evolved  as  a gas.  This  acid  scarcely  appears  at  all  when  the  quantity  of  nitric  acid 
used  is  only  1 equiv.  for  every  4 equivs.  of  potassium  in  the  prusside.  On  the  con- 
trary, it  is  a very  marked  product  when  5 equivs.  are  employed.  Precisely  under  the 
same  circumstances  that  the  carbonic  acid  is  least  in  quantity,  does  the  peculiar 
white  substance,  already  referred  to,  augment,  and  when  the  carbonic  acid  is  greatest, 
as  when  five  equivalents  of  nitric  acid  are  used,  then  scarcely  any  of  the  white  sub- 
stance is  observed.  The  carbonic  acid  is  therefore  obviously  a product  of  the  oxida- 
tion of  the  white  substance.  Five  per  cent,  of  the  white  substance  were  obtained 
when  one  equivalent  of  nitric  acid  was  used  to  oxidize  an  amount  of  yellow  prusside 
containing  4 equivs,  of  potassium ; to  ensure  this,  the  largest  quantity  obtained  by 
experiment,  the  action  of  the  acid  on  the  prusside  must  be  as  subdued  as  possible. 
The  white  substance  is  found  with  the  nitrate  of  potash,  which  has  deposited  from 
the  oxidized  liquid,  and  is  separated  from  it  by  the  solution  of  the  latter  in  water. 
The  white  substance  is  scarcely  at  all  soluble  in  cold  water,  and  therefore  may  be 
collected  and  purified  by  repeated  solutions  in  boiling  water,  in  which  it  is  only  very 
sparingly  soluble,  and  deposits  itself,  on  cooling  of  the  solution,  as  a white  crystalline 
precipitate.  It  may  also  be  sublimed  without  change  between  two  watch-glasses. 
The  following  analyses  of  this  white  substance  show  its  composition.  Analyses  I.  II. 
were  made  upon  a specimen  purified  by  sublimation ; III.  IV.  upon  a specimen 
purified  by  solution. 

I.  5’05  grs.  gave  5’004  grs.  carbonic  acid  and  2'094  grs.  water. 

II.  7‘835  grs.  gave  7’850  grs.  carbonic  acid  and  3‘236  grs.  water. 

III.  5‘947  grs.  gave  5‘95  grs.  carbonic  acid  and  2'46  grs.  water. 

IV.  6‘992  grs.  gave  6’95  grs,  carbonic  acid  and  2'886  grs.  water. 

The  nitrogen  analyses  were  made  by  Will  and  Varrentrapp’s  plan,  the  portions 
used  in  analysis  being  in  one  case  purified  by  sublimation  and  in  the  other  by  solution  : 

4'345  grs.  gave  2T835  grs.  platinum  salt. 

7-027  grs.  gave  35’74  grs.  platinum  salt. 


Purified  by  sublimation.  Purified  by  solution. 


Carbon 

, '27-024 

A 

27-324 

'27-255 

"I 

27- 108 

2 

12 

Calculated. 

27-27 

Nitrogen  . . . . 

31-583 

31-583 

31-961 

31-961 

1 

14 

31-81 

Hydrogen  . . . 

4-607 

4-589 

4-594 

4-586 

2 

2 

4-54 

Oxygen  

36-786 

36-584 

36-190 

36-345 

2 

16 

36-38 

100-000 

100-000 

100-000 

100-000 

100-00 

The  carbon  is  to  the  nitrogen  as  2:1,  or  in  the  same  proportion  as  cyanogen.  In 


A NEVV^  CLASS  OF  SALTS. 


485 


fact  the  formula  Cy-f  2HO  correctly  represents  the  composition,  and  the  substance 
may  be  supposed  to  be  formed  by  the  union  of  cyanogen  in  its  nascent  state  with 
2 equivs.  of  water.  When  this  white  substance  is  treated  with  acids,  it  is  converted 
into  oxalic  acid  and  ammonia.  This  fact,  together  with  the  analysis,  proves  it  to  be 
OxAMiDE*.  Its  occurrence  in  a process  of  oxidation  is  very  surprising,  and  perhaps 
may  throw  some  doubts  on  the  theoretical  composition  ascribed  to  it,  2CO+NH2. 
There  is  little  doubt  that  this  substance  is  the  same  as  that  observed  by  VAUQUELiN-f- 
in  a watery  solution  of  cyanogen,  which  however  was  not  analysed  by  him.  The 
description  which  he  gives  applies  closely  to  oxamide.  Wohler;]:  also  observed  two 
substances  in  a watery  solution  of  cyanogen,  one  of  which  may  be  this  body.  The 
appearance  of  carbonic  acid  is  now  explained,  as  it  is  obviously  due  to  an  oxidation 
of  the  oxalic  acid  produced  by  the  transformation  of  the  oxamide. 

Section  II. — General  remarhs  on  the  Nitroprussides. 

9.  The  nitroprussides  are  salts  with  characters  so  decided,  that  they  cannot  be  con- 
founded with  any  known  series  of  compounds.  They  are  generally  highly  coloured — 
the  salts  of  potassium,  ammonium,  sodium,  barium,  calcium  and  lead  being  of  a dark 
red  or  ruby  colour ; they  are  readily  soluble  in  water,  and  communicate  a dark  red 
colour  to  the  solution.  Alcohol  does  not  precipitate  these  salts  from  their  solutions. 
The  soluble  nitroprussides  crystallize  readily,  yielding  large  and  well-defined  crystals. 
The  nitroprussides  of  copper,  zinc,  iron,  nickel,  cobalt  and  silver,  are  either  wholly  or 
nearly  insoluble. 

The  following  Table  exhibits  some  of  the  characteristic  reactions  of  a soluble  nitro- 
prusside : — 


Reagents. 

Behaviour  of  the  nitroprusside. 

Sulphides  of  the  alkaline  metals  

Magnificent  transitory  purple  colour. 

Sulphuretted  hydrogen 

Produces  prussian  blue,  a prusside  and  peculiar  compound. 

Neutral  salts  of  lead  

No  change. 

Basic  salts  of  lead  

White  precipitate,  after  a time  in  strong  solution. 

Persalts  of  mercury  

No  change. 

Proto-  and  persalts  of  tin  

No  change. 

Salts  of  zinc  

Light  salmon-coloured  precipitate. 

Salts  of  copper  

Light  green  precipitate. 

Salts  of  nickel  

Dirty  white  precipitate. 

Salts  of  cobalt  

Flesh-coloured  precipitate. 

Protosalts  of  iron  

Salmon-coloured  precipitate. 

Persalts  of  iron  

No  change. 

Caustic  alkalies  

Turn  the  red  coloured  solutions  of  an  orange  colour. 

The  beautiful  colour  immediately  produced  on  the  addition  of  a soluble  sulphide, 
is  a most  marked  character  of  the  nitroprussides.  This  purple  coloration  is  most  in- 

* In  the  descriptions  of  oxamide,  it  is  usual  to  state  that  all  acids  convert  it  into  oxalic  acid  and  ammonia. 
It  is  however  very  readily  soluble  in  concentrated  sulphuric  acid,  from  which  it  is  again  precipitated  unchanged 
by  the  addition  of  water. 

t Ann.  de  Chim.  et  de  Phys.  ix.  113;  xxii.  132. 

3 R 


MDCCCXLIX. 


J PoGG.  Ann.  XV.  627. 


486 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


tense,  and  enables  the  detection  of  the  most  minute  quantity  of  either  reagent.  As 
a test  for  the  presence  of  sulphides  it  is  wonderfully  useful,  enabling  minute  quan- 
tities of  them  to  be  found  in  circumstances  where  the  ordinary  means  of  testing  alto- 
gether fails  to  denote  their  presence.  This  purple  coloration  is  however  only  transi- 
tory, the  compound  soon  breaking  up  into  various  substances,  among  which,  hydro- 
cyanic acid,  ammonia,  nitrogen,  oxide  of  iron,  a ferrocyanide,  a sulphocyanide  and  a 
hyponitrite  may  be  recognized. 

The  soluble  nitroprussides  are  decomposed  when  sulphuretted  hydrogen  is  passed 
through  them,  oxide  of  iron,  prnssian  blue,  sulphur,  a ferrocyanide,  and  a peculiar 
sulphur  compound  being  among  the  products  of  decomposition. 

The  alkalies  decompose  the  soluble  nitroprussides  when  their  solutions  are  mixed 
together  and  boiled.  The  products  of  the  transformation  in  this  case  are  oxide  of 
iron,  nitrogen,  a ferrocyanide  and  a hyponitrite.  An  excess  of  ammonia,  even  in  the 
cold,  gradually  decomposes  the  nitroprussides,  nitrogen  gas  being  evolved,  and  a 
peculiar  uncrystallizable  black  compound  remains  as  the  result  of  the  decomposi- 
tion. 

Sulphurous  acid,  the  sulphites  and  hyposulphites  exert  no  apparent  action  on  the 
nitroprussides.  They  are  however  wholly  decomposed  by  boiling  them  with  con- 
centrated sulphuric  acid ; during  this  decomposition,  the  peculiar  purple  colour  due 
to  sulphides  is  observed. 

Chlorine  does  not  produce  any  change  when  passed  through  solutions  of  the  nitro- 
prussides. 

Prussian  blue  dissolves  in  an  excess  of  some  of  the  nitroprussides,  forming  a beau- 
tiful blue  solution ; when  the  prussian  blue  is  in  excess,  it  is  able,  under  certain 
circumstances  (see  § 5),  to  remove  the  soluble  nitroprusside  from  solution,  but  it 
again  yields  it  up  to  boiling  though  not  to  cold  water. 

Some  of  the  nitroprussides  are  very  permanent  and  suffer  no  change  in  solution, 
either  by  exposure  to  the  air  or  by  the  action  of  heat.  Several,  on  the  contrary,  espe- 
cially nitroprussic  acid,  the  nitroprussides  of  barium,  calcium  and  ammonium,  de- 
compose partially,  either  when  their  solutions  are  long  kept,  or  speedily  when  they 
are  boiled.  Some  of  the  products  of  decomposition  are  dissolved  by  the  still  unde- 
composed nitroprusside,  and  cannot  be  again  separated  from  them  by  crystallization. 

After  this  general  idea  of  the  habits  of  the  nitroprussides,  their  individual  salts 
and  their  transformations  may  be  more  easily  studied. 

Nitroprussic  Acid. 

10.  This  acid  may  be  obtained  in  solution  by  decomposing  nitroprusside  of  silver 
with  an  equivalent  quantity  of  hydrochloric  acid,  or  by  precipitating  nitroprusside  of 
barium  with  an  equivalent  quantity  of  sulphuric  acid.  It  may  also  be  obtained,  but 
in  a less  pure  state,  by  precipitating  nitroprusside  of  potassium  dissolved  in  a small 
quantity  of  water,  and  diluted  with  several  times  its  volume  of  alcohol,  with  an  alco- 


A NEW  CLASS  OF  SAI.TS. 


487 


holic  solution  of  tartaric  acid,  the  quantity  of  the  latter  being  just  sufficient  to  form 
bitartrate  of  potash  with  the  potassium  ; but  as  the  acid  dissolves  some  of  the  latter 
salt,  this  process  does  not  yield  a pure  product. 

A dark  red-coloured  solution,  strongly  acid,  is  obtained  by  these  methods.  Ether 
does  not  precipitate  the  acid  as  it  does  ferrocyanic  acid.  Soon  however  the  solution 
begins  to  form  hydrocyanic  acid,  and  either  to  deposit  oxide  of  iron  or  to  hold  iron 
in  solution,  which  maybe  detected  by  a prusside.  When  this  change  has  taken  place, 
evaporation  in  vacuo  over  sulphuric  acid  yields  crystals  of  the  acid,  which  is  how- 
ever found  to  contain  a small  quantity  of  an  impurity,  probably  of  a cyanide  of  iron, 
which  cannot  be  separated  by  crystallization,  or  any  other  of  the  numerous  methods 
tried.  The  amount  of  this  impurity  is  from  2 to  3 per  cent.  This  crystalline  acid 
belongs  to  the  oblique  system,  and  its  crystals  are  described  and  measured  in  a 
further  part  of  this  paper,  together  with  its  analyses.  It  possesses  all  the  properties 
of  nitroprussic  acid,  and  only  differs  by  containing  this  small  quantity  of  impurity. 
The  perfectly  pure  acid  in  crystals  has  not  been  obtained,  notwithstanding  very  many 
efforts  to  obtain  this  desirable  result.  Fide  page  499. 

Nitr'oprusside  of  Sodium. 

11.  This  salt  is  the  most  readily  procured,  in  a crystallized  state,  of  all  the  nitro- 
prussides ; it  may  be  obtained  by  decomposing  the  nitroprussides  of  copper  or  iron 
by  means  of  soda,  filtering  from  the  oxides  of  these  metals  and  evaporating  the  solu- 
tion by  a gentle  heat.  When  prepared  from  the  iron  salt,  it  is  apt  to  contain  a little 
iron  in  excess. 

Nitroprusside  of  sodium  is  however  most  easily  prepared  in  the  following  manner: — 
1 equiv.  of  yellow  prusside  of  potassium  is  digested  with  5 equivs.  nitric  acid,  as  de- 
scribed in  page  481,  until  the  solution  precipitates  salts  of  protoxide  of  iron  of  a 
slate  colour.  It  is  now  neutralized  with  carbonate  of  soda,  both  solutions  being- 
employed  cold.  The  neutralized  liquid  is  now  boiled,  and  the  green  precipitate  is 
separated  by  filtration  from  the  dark  red-coloured  solution.  This  is  now  evaporated 
down  and  again  filtered  from  a brown  precipitate  which  falls  during  evaporation. 
The  nitrates  of  soda  and  potash  are  allowed  to  crystallize  out. 

The  dark  red  solution  is  now  evaporated  on  the  sand-bath,  and  during  evaporation 
prismatic  crystals  separate  from  the  hot  solution.  These  are  removed,  dissolved  in 
water,  and  again  crystallized  by  allowing  the  solution  to  cool.  The  reason  of  taking 
the  crystals  from  the  hot  solution  in  the  first  instance  is  to  obtain  them  uncontami- 
nated with  the  nitrates,  which  are  more  soluble  in  hot  water  than  this  nitroprus- 
side. By  this  process  any  quantity  of  the  nitroprusside  of  sodium  may  be  obtained 
in  fine  large  ruby-coloured  crystals. 

Properties. — This  salt  crystallizes  in  fine  ruby-coloured  prisms,  which  have  been 
measured  by  Prof.  Miller. 


3 R 2 


488 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


Symbols  : — a 100,  Z(010,  el01,r0ll,mll0,  x211.  xis  common  to  the  zones  em,ra. 
The  angles  between  the  normals  to  the  faces  are,— 


o 


ha  90  0 

ea  68  16 
ee'  43  28 
rb  62  26 
rr'  55  8 

ma  52  38'5 
mb  37  2T5 
mm!  74  43 
rm  68  25 
re  34  34 
em  77  1 

xm  49  24 
en  27  37 


V 


b 


Nitroprusside  of  sodium  resembles  very  much  in  appearance  the  ordinary  red 
prusside  of  potassium  when  the  latter  salt  is  crystallized  from  alkaline  solutions*. 

Nitroprusside  of  sodium  is  not  at  all  deliquescent,  but  is  very  soluble  in  water, 
dissolving  in  times  its  weight  of  water'f'  at  60°.  It  is  still  more  soluble  in  hot 
water,  but  appears  to  have  a point  of  less  solubility  at  a particular  temperature,  for 
it  may  easily  be  crystallized  by  keeping  its  hot  solution  on  the  sand-bath,  while  it 
may  not  do  so  on  cooling. 

It  is  decomposed  by  mixing  it  with  excess  of  alkali,  and  suffers  the  singular  trans- 
formations with  sulphurets  of  the  alkaline  metals  which  have  been  already  alluded 
to.  It  undergoes  no  change  in  weight  when  heated  to  212°,  and  therefore  does  not 
lose  water  in  the  water-bath. 

The  following  analyses  were  made  by  heating  the  salt  with  sulphuric  acid,  and 
estimating  the  iron  as  peroxide,  the  sodium  as  sulphate  of  soda: — 

Analyses  I.  and  II.  were  made  upon  a salt  obtained  by  acting  on  nitroprusside  of 
iron  with  caustic  soda.  Analyses  III.  and  IV.  from  a salt  prepared  from  nitroprusside 
of  copper.  Analyses  V.  VI.  and  VII.  from  the  process  last  described,  by  acting  on 
yellow  prusside  of  potassium  with  nitric  acid  and  neutralizing  with  carbonate  of  soda  ; 
and  analyses  VIII.  and  IX.  from  another  preparation  in  the  same  vray. 

r I.  1 T800  grs.  gave  3*300  grs.  peroxide  of  iron  and  5*870  grs.  sulphate  of  soda. 
In.  10*300  grs.  gave  2*930  grs.  peroxide  of  iron  and  5*000  grs.  sulphate  of  soda. 

* Red  prussiate  of  potash  crystallizes  more  easily  and  with  much  greater  beauty  from  alkaline  than  from 
neutral  or  acid  solutions ; the  reason  being  that  the  excess  of  alkali  decomposes  a small  quantity  of  a green 
precipitate,  which  crystallizes  along  with  it. 

t 50’12  grs.  saturated  solution  at  60°  gave  14'46  salt;  in  another  experiment  42'8S  grs.  solution  gave 
12'45  grs.  salt,  both  being  dried  in  water-bath. 


A NEW  CLASS  OF  SALTS. 


489 


r III.  13'767  gi’S.  gave  3'813grs.  peroxide  of  iron  and  6‘440  grs.  sulphate  of  soda. 
^1^  IV.  21-536  grs.  gave  5-932  grs.  peroxide  of  iron  and  10-410  grs.  sulphate  of  soda. 

V.  19-610  grs.  gave  5-470  grs.  peroxide  of  iron  and  9-890  grs.  sulphate  of  soda. 

VI.  13-545  grs.  gave  3-740  grs.  peroxide  of  iron  and  6-450  grs.  sulphate  of  soda. 

VII.  15-740  grs.  gave  4-420  grs.  peroxide  of  iron. 

VIII.  13-788  grs.  gave  3-880  grs.  peroxide  of  iron  and  6-7 10  grs.  sulphate  of  soda. 
L IX.  25-155  grs.  gave  7*028  grs.  peroxide  of  iron  and  12-120  grs.  sulphate  of  soda. 
The  combustions  M^ere  made  with  chromate  of  lead, 
r I.  9-I88  grs.  gave  6-870  grs.  carbonic  acid  and  T300  gr.  water. 

II.  8-580  grs.  gave  6-315  grs.  carbonic  acid  and  1-224  gr.  water, 

r III.  13-815  grs.  gave  10-080  grs.  carbonic  acid  and  I-78O  gr.  water. 

IV.  8-765  grs.  gave  6-570  grs.  carbonic  acid  and  T280  gr.  water. 

^ V.  12-010  grs.  gave  8-790  grs.  carbonic  acid  and  T450  gr.  water. 

VI.  15-070  grs.  gave  IO-79O  grs.  carbonic  acid  and  T820  gr.  water. 

^ VII.  9-000  grs.  gave  6 580  grs.  carbonic  acid  and  M 10  gr.  water. 

VIII.  8-645  grs.  gave  6-340  grs.  carbonic  acid  and  T184  gr.  water. 

IX.  10-921  grs.  gave  8-035  grs.  carbonic  acid  and  T309  gr.  water. 

The  nitrogen  in  this  salt  was  determined  by  Dumas’  quantitative  method,  an  air- 
pump  being  used,  so  as  to  facilitate  the  expulsion  of  air  from  the  apparatus. 

I.  7*903  grs.,  by  Dumas’  quantitative  method,  gave  117  CC.  gas  ; thermometer 
11°-1  C. ; barometer  30-415  inches.  Hence  the  nitrogen  is  27-78 1 per  cent. 

II.  4-6  grs.,  also  treated  by  Dumas’  method,  gave  68  CC.  gas ; thermometer  45° 
Fahr.  ; barometer  30-742  inches.  Per-centage  of  nitrogen  28-79. 


From  Iron  Salt. 

From  Copper  Salt. 

From  Prusside  of  Potassium. 

Iron 

...  19-576 

19-912 

19-387 

19-281 

19-525 

19-320 

19-56 

19-69 

19-59 

Sodium  

...  16-114 

00 

15-160 

15-795 

16-348 

15-88 

15-90 

15-76 

Carbon  

...  20-392 

20-073 

19-899 

20-442 

19-960 

19-530 

19-94 

20-00 

20-06 

Hydrogen  ... 

1-572 

1-583 

1-437 

1-622 

1-340 

1-340 

1-37 

1-52 

1-33 

Nitrogen 

Oxygen  

***|  42-346 

42-712 

127-781 
1 16-336 

j 42-860 

128-790] 
1 14-037  J 

t 

43-25 

42-89 

43-26 

100-000 

100-000 

100-000 

100-000 

100-000 

100-00 

100-00 

100-00 

In  order  to  estimate  the  water  with  more  precision  than  can  be  done  in  an  organic 
analysis,  a portion  of  salt  was  heated  in  an  F tube  to  which  a chloride  of  calcium, 
tube  was  attached;  9*52  grs.  gave  1*20  gr.  water,  equal  to  T40  hydrogen  per  cent. 
The  above  analyses  correspond  to  the  following  calculated  formula : — 


Calculation. 

5 Iron  . . 

.....  140 

19-33 

5 Sodium 

116 

16-02 

24  Carbon 

144 

19-89 

15  Nitrogen  . 

210 

29-00 

10  Hydrogen 

10 

1-38 

13  Oxygen  . 

104 

14-38 

724 

100-00 

490 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


It  is  obvious  that  if  the  analyses  would  authorise  25  equivs.  of  carbon  instead  of  24, 
a very  much  more  simple  formula  might  be  given.  The  mean  proportion  of  iron 
to  carbon  is  19*54  : 20*03,  while  the  proportion,  5 equivs.  ; 25  equivs.  or  1 : 5,  would 
require  19*54  : 20*93  of  carbon.  Throughout  all  the  salts,  this  less  quantity  of  car- 
bon refuses  to  enrol  itself  in  the  simple  proportion  of  1 : 5,  and  necessitates  the  use 
of  the  much  more  complex  one  of  5 : 24.  The  above  formula  may  be  expressed  as 
Fcj  Cyi2  3NO,  5Na-l-10  HO. 


Nitroprusside  of  Potassium. 


12.  This  salt  may  be  obtained  in  several  ways. 

1.  By  acting  upon  prusside  of  potassium  with  nitric  acid,  exactly  as  described  under 
nitroprusside  of  sodium,  but  the  neutralization  of  the  acid  is  effected  by  carbonate  of 
potash,  instead  of  carbonate  of  soda  as  therein  described.  The  nitrate  of  potash  is 
crystallized  out  and  the  mother-liquor  is  put  in  the  hot  chamber  to  crystallize. 

2.  It  may  be  prepared  from  the  nitroprusside  of  iron,  or  better  from  the  copper 
salt,  by  decomposing  it  with  caustic  potash,  care  being  taken  to  keep  the  nitroprusside 
in  excess. 

Properties. — This  salt,  from  its  great  solubility,  is  somewhat  difficult  to  crystallize. 
It  is  apt  to  deposit  in  an  amorphous  form  ; but  this  may  be  avoided  by  a little  prac- 
tice, and  fine  large  crystals  may  be  obtained.  These  crystals  belong  to  the  oblique 
system,  and  have  been  measured  by  Prof.  Miller. 

Symbols  : — ^010,  m 1 10,  5 012,  e 101,  rill. 

Angles  between  normals  to  the  faces  : — 


ah  30  0 

rb  54  5 

mb  49  46 
sh  68  52 
em  113  55 
57  7 
sm  69  3 


The  axis  of  the  zone  mb,  makes  an  angle  of  57°  56'  with  that  of  the  zone  rb,  and  an 
angle  of  71°  O'  with  the  axis  of  the  zone  sb. 

This  salt  dissolves  in  its  own  weight  of  water  at  60°;  60*06  grs.  of  a saturated 
solution  of  this  salt  evaporated  in  the  water-bath  left  30*40  grs.  of  the  salt.  It  is 
not  precipitated  from  its  solution  by  alcohol.  With  caustic  potash  it  unites  and  forms 
a salt  which  is  described  in  a further  part  of  the  paper.  Nascent  hydrogen  does  not 
decompose  it.  Hydrogen,  chlorine  and  sulphurous  acid  were  passed  through  both 
cold  and  hot  solutions  of  the  salt  without  effecting  any  change.  It  is  slightly  deli- 
quescent, and  acquires  a greenish  shade  when  exposed  to  light ; its  solutions  on  long 
keeping  deposit  prussian  blue  and  become  partially  decomposed. 

The  crystals  of  this  salt  are  of  a dark  red  colour. 


A NEW  CLASS  OF  SALTS. 


491 


The  analysis  was  made  by  decomposing  the  salt  by  Nordhausen  sulphuric  acid. 
The  following  estimations  give  the  amount  of  water  lost  in  the  water-bath  : — 

I.  14'865  grs.  lost  T765  grs.,  or  ir873  per  cent. 

II.  15*455  grs.  lost  T855  grs.,  or  12*002  per  cent. 

III.  12*430  grs.  lost  1*480  grs.,  or  11*906  per  cent. 

IV.  20*155  grs.  lost  2*245  grs.,  or  11*138  per  cent. 

Mean  . . 11*730 

The  inorganic  analyses  yielded  the  following  results  : — 

I.  23*905  grs.  gave  6*479  grs.  peroxide  of  iron  and  13*837  grs.  sulphate  of  potash. 

II.  20*145  grs.  gave  5*525  grs.  peroxide  of  iron  and  12*105  grs.  sulphate  of  potash. 

III.  13*015  grs.  gave  3*550  grs.  peroxide  of  iron  and  7‘660grs.  sulphate  of  potash. 

IV.  12*945  grs.  gave  3*536  grs.  peroxide  of  iron  and  7'600  grs.  sulphate  of  potash. 

V.  ]7‘195  grs.  gave  4*832  grs.  peroxide  of  iron. 

The  organic  analyses  were  made  with  chromate  of  lead. 

I.  7’475  grs.  gave  0*448  gr.  water  and  5*403  grs.  carbonic  acid. 

II.  7'122  grs.  gave  0*425  gr.  water  and  5*105  grs.  carbonic  acid. 


I. 

II. 

III. 

IV. 

V. 

Mean. 

Iron  . . 

18*972 

19*198 

19*093 

19*120 

18*901 

19*056 

Potassium 

25*947 

26*934 

26*385 

26*388 

.... 

26*413 

Carbon  . 

19*712 

19*548 

.... 

.... 

.... 

19*630 

Hydrogen 

0*665 

0*663 

.... 

.... 

.... 

0*664 

Nitrogen 
Oxygen  . , 

j>  34*704 

33*057 

.... 

.... 

.... 

34*237 

100*000 

100*000 

100*000 

These  results  may  be  expressed  by  the  following  calculation : — 


Calculated. 

Mean. 

5 Iron  . . 

. . 140 

18*92 

19*056 

5 Potassium 

. . 195 

26*35 

26*413 

24  Carbon  . 

. . 144 

19*46 

19*630 

3 Hydrogen 

. . 3 

0*40 

0*664 

15  Nitrogen  . 

6 Oxygen  . 

. . 210 

. . 48 

28*38  4 

6*49  J 

34*237 

740 

100*00 

100*000 

According  to  this  calculation  the  formula  of  the  salt  dried  at  2 12°  is  Fcg  Cyi2  3NO, 
5K-1-3HO  ; the  salt  loses  in  the  water-bath  1 1*73  per  cent,  of  water ; had  it  lost  12*7 
per  cent,  this  would  have  corresponded  to  12  equivs. ; 11  equivs.  would  yield  a loss 
of  10*6  per  cent. 


492 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


Nitroprusside  of  Barium. 

13.  This  salt  is  obtained  by  decomposing  nitroprusside  of  copper  by  caustic  barytes, 
avoiding  an  excess  of  the  latter.  On  filtration  a dark  red-coloured  solution  passes 
through.  When  evaporated  under  the  air-pump,  it  forms  fine  large  pyramidal  crystals. 
The  following  measurements  have  been  made  by  Prof.  Miller  of  Cambridge : — 
Symbols  : — a 100,  c 001,  r 1 1 1. 

Angles  between  normals  to  the  faces : — 


ac  90  0 

aa!  90  0 

rc  44  35 
rr'  59  30 
m 60  15 


This  salt,  out  of  a strong  solution,  also  frequently  crystallizes  in  flattened  prisms ; 
no  doubt  as  a different  hydrate. 

Nitroprusside  of  barium  is  of  a dark  red  colour,  is  easily  soluble  in  water,  and  is 
not  deliquescent.  It  deposits  a brown  precipitate  on  boiling,  resembling  oxide  of 
iron,  but  which,  in  the  specimen  examined,  also  contained  barytes.  The  salt,  after 
it  has  experienced  this  change,  crystallizes  in  the  same  form,  but  with  impurities 
which  cannot  be  separated  by  filtration  or  crystallization.  Analyses  of  this  altered 
salt  are  given,  page  504. 

The  salt  crystallized  in  the  air-pump  lost  water  in  water-bath. 

20‘415grs.  lost  at  212°  3'1'lOgrs.  water  = 15*233  per  cent. 

24*455  grs.  lost  at  210°  3*648  grs.  water  =14*917  per  cent. 

The  analyses  were  made  by  acting  upon  the  salt  by  sulphuric  acid  in  the  usual 
way. 

I.  20*791  grs.  gave  12*173  grs.  sulphate  of  barytes  and  4*180  grs.  oxide  of  iron. 

II.  17*240  grs.  gave  10*198  grs.  sulphate  of  barytes  and  3*480  grs.  oxide  of  iron. 

The  combustions  were  made  with  chromate  of  lead. 

I.  8*539  grs.  gave  1*208  gr.  water  and  4*665  grs.  carbonic  acid. 

II,  10*068  grs.  gave  1*132  gr,  water  and  5*580  grs.  carbonic  acid. 


I. 

II. 

Calculated. 

Iron  . . 

14*073 

14*129 

5 

140 

14*05 

Barium  . 

34*446 

34*791 

5 

343 

34*43 

Carbon  , 

14*899 

15*075 

24 

144 

14*45 

Hydrogen 

1*571 

1*249 

15 

15 

1*50 

Nitrogen  ' 

j- 35*011 

34*756 

15 

2101 

35*57 

Oxygen  J 

18 

144  J 

100*00 

100*00 

996 

100*00 

A NEW  CLASS  OF  SALTS. 


493 


In  the  above  analysis  the  proportion  of  carbon  to  the  iron  is  higher  than  obtained 
with  the  other  salts,  but  the  error  is  usually  on  this  side  when  chromate  of  lead,  as 
in  this  instance,  is  used  in  the  combustion.  It  will  also  be  seen  in  a further  part  of 
the  paper,  that  a carbonaceous  impurity,  probably  an  attached  cyanide,  not  separable 
by  crystallization,  but  removed  when  it  is  converted  into  a silver  salt,  is  produced 
when  a solution  of  this  salt  is  kept  for  some  time,  and  it  is  possible  that  a small 
portion  may  be  present  in  the  salt  analysed.  If  we  could  be  assured  of  the  absence 
of  all  impurity,  which  it  will  be  afterwards  seen  that  it  is  difficult  to  believe  from  the 
variable  composition  of  this  salt,  it  is  obvious  that  the  above  analyses  might  be  much 
more  simply  expressed  by  the  following  calculation: — 


2 Iron  . . . 

. 56 

Calculated. 

14*03 

2 Barium  . . 

. 137 

34*33 

10  Carbon  . . 

. 60 

15*03 

6 Hydrogen  . 

6 

1*50 

6 Nitrogen 

. 84-) 

35*11 

7 Oxygen  . . 

. 56  J 

399 

100*00 

On  the  first  formula  the  dried  salt  would  be  Fcg  Cy^g  on  the 

second  FcgCyg  NO,  Bug-f-dHO.  The  water  lost  in  the  water-bath  would  in  the  first 
case  correspond  to  20equivs.,  in  the  latter  case  to  Sequivs. 

Nitroprusside  of  Silver. 

14.  This  salt  may  be  prepared  by  adding  nitrate  of  silver  to  any  of  the  soluble 
nitroprussides. 

The  colour  of  the  salt  varies  according  to  its  state  of  preparation,  from  a fleshy 
white  to  a pale  buff.  When  dry  it  has  a flesh  colour.  It  is  insoluble  in  water, 
alcohol  and  nitric  acid.  Hydrochloric  acid  decomposes  it  with  the  formation  of 
nitroprussic  acid  and  chloride  of  silver.  The  caustic  alkalies  decompose  it,  as  they  do 
the  soluble  nitroprussides  generally : ammonia  dissolves  nitroprusside  of  silver,  but  it 
soon  deposits  white  crystals,  which  are  apt  to  be  contaminated  by  oxide  of  iron. 
These  white  shining  crystals  are  a compound  of  the  salt  with  ammonia,  and  are  quickly 
decomposed,  even  by  water  alone,  but  very  readily  by  water  acidulated  with  nitric 
acid.  Ammonia  is  now  found  in  solution  and  nitroprusside  of  silver  remains.  If  am- 
monia and  nitroprusside  of  silver  be  boiled  together,  a total  decomposition  takes  place. 

The  salt  was  decomposed  by  sulphuric  acid,  the  silver  estimated  as  a chloride  and 
the  iron  as  peroxide.  Each  salt  analysed  was  prepared  at  different  times. 

I.  14‘788grs.  gave  2'749grs.  oxide  of  iron  and  9‘925  grs.  chloride  of  silver. 

II.  22‘838grs.  gave  4‘220grs.  oxide  of  iron  and  15‘180grs.  chloride  of  silver. 

III.  16  675  grs.  gave  3T15  grs.  oxide  of  iron  and  1T09  grs.  chloride  of  silver. 

IV'.  26*545  grs.  gave  4*970  grs.  oxide  of  iron  and  17'78  grs.  chloride  of  silver. 

MDCCCXLIX.  3 s 


494 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


The  combustions  were  made  in  the  usual  way. 

I.  8*350  grs.  gave  0*252  gr.  water  and  4*045  grs.  carbonic  acid, 

II.  8*385  grs.  gave  0*234  gr.  water  and  4*150  grs.  carbonic  acid. 

III.  7’900grs.  gave  0*183  gr.  water  and  3*820  grs.  carbonic  acid. 

IV.  9*415  grs.  gave  0*120  gr.  water  and  4*577  grs.  carbonic  acid. 


As  this  salt  was  well  calculated  to  give  correct  knowledge  with  regard  to  the  com- 
position of  the  nitroprussides  generally,  the  nitrogen  was  carefully  determined  by  the 
three  best  processes,  viz.  those  of  Dumas,  Liebig  and  Bunsen. 

I.  Quantitative  estimation  of  nitrogen  ; — 

6*808  grs.  salt  gave  69  C.  C.  nitrogen  gas, 

the  thermometer  being  7°’7  C.  and  the  barometer  30*094  inches.  This  makes  the 
nitrogen  19*299  per  cent. 

II.  Liebig’s  method  : — 


Tubes. 

1. 

Vol.  mixed  gases. 
21*0 

Vol.  after  absorption. 

8*15 

Vol.  of  carbonic  acid. 

12*85 

2. 

18*4 

* 7-3 

11*1 

3. 

24*0 

9*25 

14*75 

4. 

20*15 

7*45 

12*70 

5. 

13*3 

5*35 

7*95 

6. 

26*20 

9*2 

17-0 

123*05 

46*70 

76*35 

Hence  the  proportion  of  nitrogen  to  carbonic  acid  is  as  1 : 1*63.  This,  calculated 
on  13*288,  the  mean  quantity  of  carbon,  gives  19*02  per  cent. 


Bunsen’s  method : — 

Obs.  vol.  Barom. 

inches. 

Vol.  of  mixed  gases  (moist)  . 110*8  737’7 

Vol.  after  absorption  (dry)  . 46*2  761*9 

Corrected  vol.  of  mixed  gases  . . 

Corrected  vol.  of  nitrogen 

Vol,  of  carbonic  acid 


Therm. 

16*2  C 
16*2 

66*801 

25*800 

41*001 


Col.  mere. 

217*0 

218*0 


Hence  the  proportion  of  nitrogen  to  carbonic  acid  is  as  1 : 1*589,  which  calculated 
on  13*288  carbon,  gives  19*512  per  cent. 


Iron . . . 

I. 

13*012 

11. 

12*934 

111. 

13*076 

IV. 

13*106 

Mean. 

13*032 

5 

140 

Calculated. 

13*011 

Silver  . 

50*546 

50*000 

49*925 

50*040 

50*128 

5 

540 

50*185 

Carbon . . 

18*211 

13*508 

13*177 

13*257 

13*288 

24 

144 

13*382 

Hydrogen  . 

0*330 

0*310 

0*250 

0*140 

0*257 

2 

2 

0*185 

Nitrogen  . 

19*299 

19*020 

19-512-) 

23*457 

19*277 

15 

210 

19*516 

Oxygen 

3*602 

4*228 

4*060  j 

4*118 

5 

40 

3*721 

100*000 

100*000 

100*000 

100*000 

100*000 

1076 

100*000 

A NEVy  CLASS  OF  SALTS. 


495 


With  a quantity  of  hydrogen  so  small  as  that  in  the  above  analysis,  it  is  difficult  to 
obtain  accordant  results  in  an  organic  analysis.  A portion  of  well-dried  salt  was 
therefore  heated  in  an  F tube,  to  which  a tube  filled  with  chloride  of  calcium  was 
attached. 

5*375  grs.  gave  0*085  gr.  water,  equal  to  0*175  H.  per  cent. 

4*000  grs.  gave  0*065  gr.  water,  equal  to  0*180  H.  per  cent. 

It  is  therefore  quite  certain  that  the  silver  salt  dried  at  212°  still  retains  1^  per 
cent,  of  water.  It  loses  however  this  water  at  a higher  heat  and  becomes  anhydrous. 
The  formula  of  the  silver  salt  is  therefore  Feg  Cyi2  3NO,  Ag5-l-2HO. 


Nitroprusside  of  Copper. 

15.  This  salt  is  obtained  by  adding  a solution  of  a copper  salt  to  that  of  a nitro- 
prusside. As  it  is  insoluble  in  cold  water,  and  almost  entirely  so  in  hot,  it  may  be 
washed  to  any  extent. 

It  is  of  a pale  green  colour,  which  changes  to  slate  colour  when  exposed  to  light 
in  the  moist  state.  It  is  quite  insoluble  in  alcohol.  It  is  decomposed  by  the  caustic 
alkalies,  first  passing  into  a dark  brown  basic  nitroprusside,  and  then  into  oxide  of 
copper  and  a soluble  nitroprusside. 

Nitroprusside  of  copper,  dried  in  the  hot  chamber  at  about  100°Fahr.,  still  lost 
weight  in  the  water-bath. 


45*60  grs.  lost  in  water-bath  4*525,  or  9*922  per  cent. 

25*  1 2 grs.  lost  in  water-bath  2*870,  or  11*425  per  cent. 

The  analysis  of  the  dried  salt  was  made  by  decomposing  it  with  sulphuric  acid, 
and  estimating  the  two  metals  as  oxides,  after  separating  them  in  the  usual  way  by 
sulphuretted  hydrogen. 

I.  22*24  grs.  gave  6*325  grs.  oxide  of  copper  and  6*515  grs.  peroxide  of  iron. 

II.  2 TOO  grs.  gave  6*018  grs.  oxide  of  copper  and  6*  120  grs.  peroxide  of  iron. 

The  combustions  were  made  with  chromate  of  lead  and  with  oxide  of  copper. 

I.  8*100  grs.  gave  0*230  gr.  water  and  6*343  grs.  carbonic  acid. 

II.  7'977  gi’s.  gave  0*240  gr.  water  and  6*217  gi’S-  carbonic  acid. 

III.  9*887  gi'S.  gave  0*330  gr.  water  and  7‘694  grs.  carbonic  acid. 

IV.  1 1*507  grs.  gave  0*320  gr.  water  and  8*936  grs.  carbonic  acid. 

The  nitrogen  was  determined  in  three  different  ways. 

I.  Dumas’  quantitative  method  : — 

6*226  grs.  gave  98  CC.  nitrogen  gas.  Barom.  30*105  inches.  Therm.  8°*8  C. 

II.  Bunsen’s  method  ; — 


Vol. 

Vol.  mixed  gases  (moist)  . 246*3 

Vol.  after  absorption  (dry)  . 121*1 


Barom. 

Therm. 

Col.  mere, 

inche.s. 

0 

29*988 

15*6 

219*7 

30*069 

15*4 

348*0 

3 s 2 


496 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


Corrected  vol.  of  mixed  gases  . . . 123‘180 

Corrected  vol.  of  nitrogen  ....  47*491 

Corrected  vol.  of  carbonic  acid  . . 75’689 

Hence  the  proportion  of  nitrogen  to  carbonic  acid  is  1 ; 1*593,  which  calculated  on 
the  mean  quantity  of  carbon  (21*25),  yields  31*12  per  cent,  nitrogen. 


III.  Liebig’s  method  : — 


Tubes.  Vol.  mixed  gases. 

Vol.  after  absorption. 

Vol.  of  carbonic  acid. 

1. 

21-2 

8-0 

13-2 

2. 

22-4 

9-1 

13-3 

3. 

26-0 

10-4 

15-6 

4. 

21-7 

8-2 

13-5 

5. 

28-3 

10-6 

17*7 

6. 

17*9 

6*7 

11-2 

7. 

22-2 

8-2 

14-0 

8. 

19-8 

* 7*5 

12-3 

9. 

20-0 

8-0 

12-0 

10. 

22-7 

9-0 

13-7 

11. 

28-0 

10-8 

17*2 

12. 

19-2 

7*3 

11-9 

13. 

14-6 

5-4 

9-2 

284-0 

109-2 

174-8 

Hence  the  proportion  of  nitrogen  to  carbonic  acid 

is  1 : 1-60. 

I. 

II. 

III.  IV. 

Mean. 

Calculated. 

Iron . . . 

20-506 

20-400 

....  .... 

20-453 

5 

140 

20-43 

Copper  . . 

22-708 

22-880 

....  .... 

22-794 

5 

158 

23-06 

Carbon . . 

21-351 

21-255 

21-222  21-179 

21-251 

24 

144 

21-02 

Hydrogen  . 

0-315 

0-309 

0*371  0-308 

0-325 

1 

1 

0-14 

Nitrogen  . 

29-856 

31-120 

30-980  .... 

30-652 

15 

210 

30-65 

Oxygen . . 

5-264 

4-036 



4-515 

4 

32 

4-70 

100-000 

100-000 

100-000 

685 

100-00 

The  formula  of  the  copper  salt  is  therefore  Fe5Cyi2 

3NO,  CU5  + HO. 

Nitroprusside  of  Iron. 

16.  This  salt  is  obtained  by  adding  sulphate  of  the  protoxide  of  iron  to  a soluble 
nitroprusside.  When  the  solutions  are  dilute  the  precipitate  does  not  at  first  appear ; 
as  however  it  is  very  sparingly  soluble,  it  may  be  purified  by  washing  either  with  hot 
or  cold  water. 

This  salt  is  a salmon-coloured  precipitate,  nearly  though  not  absolutely  insoluble 
in  water  ; it  is  more  soluble  in  water  rendered  acid  by  nitric  acid.  It  is  decomposed 
by  caustic  alkalies,  with  the  precipitation  of  oxide  of  iron  and  the  formation  of  a 


A NEW  CLASS  OF  SALTS. 


497 


soluble  niti’oprusside.  Before  however  being  completely  decomposed,  a dark-coloured 
basic  nitroprusside  of  iron  is  produced. 

A salt  dried  in  the  hot  chamber,  at  a temperature  about  90°  Fahr.,  still  lost  water 
when  exposed  in  the  water-bath  : — 

14‘162  grs.  lost  at  212°  2‘890  grs.,  or  20‘406  per  cent. 

10’893  grs.  lost  at  212°  2'320  grs.,  or  21-298  per  cent. 

17-500  grs.  lost  at  212°  3-545  grs.,  or  20-257  per  cent. 

In  the  two  first  analyses  given  below,  the  iron  was  determined  by  decomposing  the 
salt  by  sulphuric  acid,  oxidizing  with  nitric  acid  and  precipitation  by  ammonia.  The 
third  estimation  was  by  calcination,  a little  nitrate  of  ammonia  being  used  to  effect 
complete  oxidation. 

I.  1 8-075  grs.  gave  9-917  grs.  peroxide  of  iron. 

II.  30-935  grs.  gave  16-900  grs.  peroxide  of  iron. 

III.  9-220  grs.  gave  4-995  grs.  peroxide  of  iron. 

The  combustions  were  performed  with  chromate  of  lead. 

I.  7-2I8  grs.  gave  0-717  gi’-  water  and  5-255  grs.  carbonic  acid. 

II.  7*347  grs.  gave  0-810  gr.  water  and  5-360  grs.  carbonic  acid. 

III.  6-360  grs.  gave  0-693  gr.  water  and  4-695  grs.  carbonic  acid. 

The  nitrogen  was  determined  by  Dumas’  quantitative  method. 

5-427  grs.  gave  86  CC.  nitrogen  gas,  the  thermometer  being  48°-7  Fahr.  (9-4  Cent.) 
and  the  barometer  29-285  inches. 


Iron  . . . 

I. 

. 38-406 

II. 

38-241 

III. 

37-922 

Mean. 

38-189 

10 

280 

Calculated 

38-35 

Carbon  . . 

. 19-855 

19-896 

20-136 

19-962 

24 

144 

19-72 

Nitrogen  . 

. 29-285 

29-285 

29-285 

29-285 

15 

210 

28-76 

Hydrogen 

1-103 

1-224 

1-210 

1-179 

8 

8 

1-09 

Oxygen  . 

. 11-351 

11-354 

11-447 

11-385 

11 

88 

12-08 

100-000 

100-000 

100-000 

100-000 

730 

100-00 

The  formula  of  the  iron  salt,  dried  at  212°,  would  therefore  be 

Feg  Cy^2  3NO  Fe5+8HO. 

Nitroprusside  of  Zinc. 

17.  This  salt  is  prepared  by  precipitating  one  of  the  soluble  salts  of  zinc  by  a nitro- 
prusside. It  is  a salmon-coloured  precipitate,  of  a more  fleshy  colour  than  the  iron  salt. 
When  formed  slowly,  as  when  muriatic  acid  and  zinc  are  made  to  act  on  nitroprusside 
of  soda,  it  is  of  a deep  orange  colour. 

Nitroprusside  of  zinc  is  very  slightly  soluble  in  cold  water,  rather  more  so  in  hot 
water.  In  its  behaviour  to  reagents  it  acts  exactly  like  the  iron  nitroprusside.  It 
was  analysed  by  decomposing  it  with  sulphuric  acid,  separating  the  iron  by  succinate 
of  ammonia  and  determining  the  zinc  as  a carbonate. 


498 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


24' 14  grs.  gave  6'92  grs.  peroxide  of 

iron  and  6'70 

grs.  oxide 

zinc. 

9'43  grs.  gave  7*10  grs. 

, carbonic  acid  and  0'335 

gr.  water. 

Calculated. 

Iron 

20'07 

5 

140 

20-11 

Zinc 

22-26 

5 

160 

22-98 

Carbon  .... 

20-53 

24 

144 

20-69 

Hydrogen  . . 

0-39 

2 

2 

0-28 

Nitrogen  I 

36-75 

15 

210  ■) 

35-94 

Oxygen  J 

5 

40  J 

100-00 

696 

100-00 

This  analysis  would  lead  to  the  formula  FegCyjg  3NO  Zn5+2HO. 


Section  III. — Changes  experienced  hy  certain  Nitroprussides  when  their  solutions 

are  heated  or  hept. 

18.  Several  of  the  nitroprussides,  especially  nitroprussic  acid,  nitroprussides  of 
ammonium,  barium  and  calcium,  deposit  either  prussian  blue  or  oxide  of  iron  when 
their  solutions  are  heated  or  are  kept  for  sometime.  The  residual  liquid,  after  evapo- 
ration, yields  crystals  of  the  same  shape  and  exactly  of  the  same  properties  as  before. 
Analysis  however  shovvs  that  some  change  has  resulted  in  their  composition,  for  the 
iron  or  electro-negative  metal  is  now  in  greater  than  atomic  proportion  to  the  electro- 
positive metal.  The  proportion  of  carbon  is  also  somewhat  different.  Still  the  differ- 
ence in  composition  is  not  very  considerable,  although  decidedly  marked ; it  is  not 
however  sufficient  to  cause  any  obvious  alteration  in  their  general  properties.  In 
fact,  there  is  an  attached  impurity,  probably  a cyanide  of  iron,  which  cannot  now  be 
removed  by  crystallization,  precipitation,  digestion  with  nitric  acid,  or  any  of  the 
ordinary  means  of  purification.  This  impurity,  if  it  be  one,  remains  so  obstinately 
attached  that  all  methods  of  purification  have  quite  failed  to  remove  it.  This  circum- 
stance, before  it  was  understood,  had  thrown  the  greatest  difficulties  in  the  way  of 
the  inquiry,  and  protracted  it  to  a most  tedious  length  by  preventing  the  attainment 
of  accordant  results.  It  is  to  prevent  the  like  inconvenience  to  those  who  repeat  these 
experiments  that  this  section  of  the  paper  is  specially  devoted.  Attention  has  pre- 
viously been  drawn  to  the  fact,  that  the  nitroprussides  form  chemical  compounds 
with  the  cyanides  of  iron.  This  seems  to  be  a case  of  the  same  kind,  but  of  more 
ultimate  union.  The  impurity  or  chemically  attached  cyanide  in  this  case  appears 
to  be  Fe  Cyg,  or  perhaps  FeCy+H  Cy,  judging  from  analysis  only,  for  its  separation 
has  not  been  accomplished.  The  proportion  in  which  it  is  present  is  very  small, 
generally  only  2(Fe  Cyg)  to  7 equivs.  of  a nitroprusside,  or  if  it  be  a chemical  com- 
pound, 7(Fe5  Cyi2  3NO-l-5R)-{-Fe2  Cy4.  Still  as  the  crystalline  form  and  all  the 
properties  of  the  nitroprussides  remain  unchanged,  we  can  scarcely  view  its  presence 
in  any  other  light  than  as  an  impurity.  Several  of  the  nitroprussides,  viz.  nitroprussic 


A NEW  CLASS  OF  SALTS. 


499 


acid  and  the  nitroprussides  of  ammonium  and  calcium,  have  not  yet  been  obtained 
free  from  this  impurity,  and  are  therefore  described  in  this  section. 

Nitroprussic  Acid. 

19.  The  mode  of  preparation  of  this  acid  has  been  already  described  at  page  486. 
It  is  however  most  readily  prepared  from  nitroprusside  of  silver  by  adding  to  it  as 
much  hydrochloric  acid  as  suffices  to  form  chloride  of  silver  with  the  silver  in  the 
salt.  The  dark  red  solution  thus  obtained  soon  evolves  hydrocyanic  acid,  even  in 
the  cold,  and  after  a time  prusside  of  potassium  indicates  the  presence  of  iron  in  solu- 
tion. If  the  solution  be  heated,  it  deposits  abundance  of  a brown  precipitate  resem- 
bling oxide  of  iron.  When  the  latter  is  separated  by  filtration,  and  the  solution  is 
evaporated  in  vacuo  over  sulphuric  acid,  crystals  are  formed  and  may  be  separated  ; 
they  must  be  dried  over  sulphuric  acid,  as  they  are  exceedingly  deliquescent.  These 
crystals  belong  to  the  oblique  system,  but  on  account  of  their  excessive  tendency  to 
deliquesce,  it  is  difficult  to  measure  their  angles  with  accordant  results.  The  angles 
between  normals  to  the  only  faces  which  gave  results  to  be  depended  on,  are  stated 
by  Prof.  Miller  to  be  as  follows : — 

ec  36  57 
e'c'  36  57 
ee'  1 06  6 

It  will  be  seen  that  the  equality  of  the  angles  ec  and  e’c'  is  a tolerably  certain  indi- 
cation that  the  crystals  belong  to  the  oblique  system. 

The  acid  made  by  the  action  of  hydrochloric  acid  on  nitroprusside  of  silver,  and 
evaporated  over  sulphuric  acid  in  the  cold,  crystallized  (light  being  excluded)  without 
the  deposition  of  oxide  of  iron,  but  the  smell  of  hydrocyanic  acid,  accompanied  by  a 
peculiar  pungent  smell,  was  strongly  perceptible.  Analysis  shows  that  these  crystals 
are  the  same  as  those  obtained  from  a boiled  solution. 

Properties  of  the  Crystallized  Acid. — The  crystallized  acid  is  of  a dark  red  colour, 
and  has  a very  acid  reaction,  the  crystals  being  generally  flattened  and  of  tolerable 
size.  They  are  quite  as  deliquescent  as  chloride  of  calcium.  They  dissolve  to  a large 
extent  in  water,  and  are  also  soluble  in  alcohol  and  in  ether.  They  may  be  dried  in 
the  water-bath  without  change,  but  their  aqueous  solution  cannot  be  boiled  without 
decomposition. 

The  following  analyses  were  made  on  crystals  obtained  from  a boiled  solution,  and 
were  dried  at  212°.  The  acid  was  that  made  by  the  action  of  hydrochloric  acid  on 
the  silver  salt.  Nos.  I.  II.  and  III.  were  preparations  made  at  distinct  times. 

The  iron  w^as  determined  by  calcination  and  by  treating  the  residual  oxide  with 
nitrate  of  ammonia. 

I.  2'345  grs.  gave  0'800  gr.  peroxide  of  iron. 

II.  3’915  grs.  gave  T325  gr.  peroxide  of  iron. 

III.  3'580  grs.  gave  T220  gr.  peroxide  of  iron. 


500 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


The  combustions  were  made  in  the  usual  way. 

I.  7’720  gi'S.  gave  7’005  grs.  carbonic  acid  and  I *175  gr.  water. 

II.  lO'SlO  grs.  gave  9*880  grs.  carbonic  acid  and  T665  gr.  water. 

III.  4*385  grs.  gave  3*980  grs.  carbonic  acid  and  0*700  gr.  water. 

An  estimation  of  nitrogen  by  Bunsen’s  method  gave  the  following  result : — 


Obs.  vol. 

Barom. 

inches. 

Therm. 

Col.  Merc. 

Vol.  of  mixed  gases  (moist)  . 

. 89*5 

29*994 

foe. 

152*7 

Vol.  after  absorption  (dry)  . 

. 37-4 

30*015 

9*2  C. 

205*2 

Corrected  vol.  of  mixed  gases  , . . 52*995 

After  absorption  of  carbonic  acid  . . 20*570 


Nitrogen 32*425 

Hence  the  proportion  of  nitrogen  to  carbonic  acid  is  1 : 1*576. 


Iron  .... 

I. 

. 23*88 

II. 

23*69 

III. 

23*85 

Mean. 

23*80 

5 

140 

Calculated 

24*26 

Carbon  . . 

. 24*74 

24*92 

24*75 

24*80 

24 

144 

24*95 

Hydrogen  . 

. 1*69 

1*71 

1*77 

1*72 

11 

11 

1*90 

Nitrogen . . 

. 36*73 

36*73 

36*73 

36*73 

15 

210 

36*39 

Oxygen  . . 

. 12*96 

12*95 

12*90 

12*95 

9 

72 

12*50 

100*00 

100*00 

100*00 

100*00 

577 

100*00 

The  calculated  result,  especially  as  regards  the  hydrogen,  is  not  sufficiently  close  to 
be  the  true  expression  of  the  analysis,  but  it  is  here  given  to  show  how  far  the  acid 
differs  from  pure  nitroprussic  acid.  It  is  indeed  probable  that  the  acid  dried  at  212° 
only  contains  10  equivs.  of  water. 

The  acid  is  so  remarkably  deliquescent  that  it  is  very  difficult  to  ascertain  how 

much  the  crystals  lose  in  the  water-bath.  The  following  analysis  of  the  salt  dried 

in  vacuo  over  sulphuric  acid  shows  a higher  state  of  hydration.  The  sample  analysed 
had  never  been  heated,  even  in  solution,  so  that  it  evaporated  without  the  deposition 
of  oxide  of  iron.  Still  the  oxide  was  detected  in  the  mother-liquor  by  ferrocyanide 
of  potassium. 

I.  3*225  grs.  gave  TO  10  gr.  peroxide  of  iron. 

II.  3*235  grs.  gave  1*020  gr.  peroxide  of  iron. 

I.  5*830  grs.  gave  5*020  grs.  carbonic  acid  and  1*09  gr.  water. 

II.  8*225  grs.  gave  7'060  grs.  carbonic  acid  and  1*51  gr.  water. 


I. 

II. 

Mean. 

Iron  . . 

. . . 21*92 

22*07 

21*99 

Carbon 

. . . 23*48 

23*32 

23*40 

Hydrogen 

. . . 2*07 

2*03 

2*05 

Nitrogen  . 
Oxygen  . 

■ ■ '1 52*53 

52*58 

52*56 

100*00 

100*00 

100*00 

A NEW  CLASS  OF  SALTS. 


501 


A silver  salt  made  from  the  well-crystallized  acid  showed  that  the  iron  was  in 
excess,  and  that  the  carbon  was  in  the  usual  proportion  (see  p.  506).  The  analyses 
of  these  silver  salts  are  given  further  on,  in  order  to  avoid  repetition.  The  discus- 
sion as  to  the  constitution  of  the  acid  is  also  deferred  to  that  place. 

Nitroprusside  of  Ammonium, 

20.  When  ammonia  is  added  to  an  excess  of  nitroprusside  of  iron  the  latter  is  de- 
composed, oxide  of  iron  being  precipitated,  but  during  the  action  nitrogen  gas  is 
evolved.  If  the  red-coloured  solution  caused  by  filtration  be  evaporated  in  the  air- 
pump,  a difficultly  crystallizable  salt  is  obtained,  which  very  readily  decomposes, 
turning  blue  in  the  water-bath,  and  even  when  dried  over  sulphuric  acid  m vacuo. 
This  salt  is  probably  the  true  nitroprusside  of  ammonium,  but  it  has  not  been  obtained 
pure  for  analysis.  If  a solution  of  this  salt  be  heated,  prussian  blue  is  deposited,  and 
the  filtered  dark-red  liquid,  being  evaporated  by  a gentle  heat,  now  crystallizes  in  a 
warm  place  very  readily,  and  in  fine  large  red  crystals,  which  are  so  dark  as  to  be 
almost  of  a black  colour.  These  have  been  measured  by  Prof,  Miller  ; they  are 
prismatic,  but  the  angles  given  are  only  approximative,  the  faces  of  the  crystal  exa- 
mined being  imperfect. 

Symbols : — c 00 1 , w 1 1 0,  w 01 1 . 

Angles  between  normals  to  the  faces  : — 

me  90  0 

mm!  88  4 

uc  55  3 

uu'  110  6 

They  are  twin  crystals,  the  twin  faces  being  m. 

This  salt  is  very  soluble  in  water,  from  which  it  is  not  precipitated  by  alcohol.  It 
is  very  slightly  deliquescent.  The  salt  dried  in  air  loses  water  in  the  water-bath. 

18'648  grs.  lost  at  212°  2'928  grs.,  or  15'701  per  cent. 

10*915  grs.  lost  at  212°  T800gr.,  or  16*491  per  cent. 

11*502  grs.  lost  at  212°  1*948  gr.,  or  16*936  per  cent. 

45*400  grs,  lost  at  212°  6*850  grs.,  or  15*088  per  cent. 

16*054 

The  iron  was  determined  by  calcination. 

I.  10*905  grs.  gave  3*455  grs.  peroxide  of  iron. 

II.  12*954  grs.  gave  4*070  grs.  peroxide  of  iron. 

The  combustions  made  with  chromate  of  lead  gave  the  following  results : — 

I.  9*822  grs.  gave  2*903  grs.  water  and  8*251  grs.  carbonic  acid. 

II.  12*765  grs.  gave  3*682  grs.  water  and  10*494  grs.  carbonic  acid. 

III.  7*215  grs.  gave  2*0 10  grs.  water  and  6*020  grs.  carbonic  acid. 

The  nitrogen  was  determined  by  Dumas’  quantitative  method. 

MDCCCXLIX.  3 T 


502 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


I.  4*494  grs.  salt  gave  112  C.C.  gas,  the  therm,  being  47°^  Fahr.,  barom.  29*844  in. 
II.  3*372  grs.  salt  gave  83  C.C.  gas,  the  therm,  being  50°  Fahr.,  barom.  29*550  in. 
This,  calculated  on  22*7  per  cent,  carbon,  gives  43*619  per  cent,  nitrogen. 

Again,  8*747  grs.  salt  distilled  with  a weak  solution  of  soda,  gave  a distillate  which, 
collected  in  hydrochloric  acid,  yielded  15*021  grs.  platinum  salt. 


Iron  . . . 

I. 

. 22*177 

II. 

21*993 

III. 

Mean. 

22*085 

Carbon  . . 

. 22*901 

22*420 

22*755 

22*692 

Hydrogen 

. 3*283 

3*204 

3*095 

3*194 

Nitrogen  . . 

. 46*894 

45*076 

.... 

45*985 

Oxygen  . . 

4*745 

7*307 

.... 

6*044 

100*000 

100*000 

100*000 

The  ammonium  per  cent,  from  the  amount  of  platinum  salt  is  13*872. 

It  is  obvious  that  there  is  little  hydrogen  as  water,  for  the  greatest  part  is  required 
to  make  up  the  ammonium  (13*872  per  cent,  requires  3*08  hydrogen).  Reserving, 
as  in  the  other  cases,  the  discussion  as  to  the  cause  of  difference  between  this  salt 
and  the  pure  nitroprusside,  it  will  be  convenient  to  give  the  calculation  for  nitro- 
prusside  of  ammonium,  of  which  the  formula  would  be  Fe5Cyi2  3NO,  5NH4+2HO. 


5 Iron  . . . 

...  140 

22*36 

24  Carbon  . . 

...  144 

23*00 

20  Nitrogen  . 

...  280 

44*72 

22  Hydrogen  , 

...  22 

3*51 

5 Oxygen . . 

...  40 

6*41 

626 

100*00 

The  hydrogen,  but  not  the  other  constituents,  would  agree  better  with  the  above 
formula  minus  2 equivs.  of  water  ; the  hydrogen  by  the  latter  would  be  3*28  per  cent. 


Nitroprusside  of  Calcium. 


21.  To  prepare  this  salt,  nitroprusside  of  iron  or  of  copper  is  decomposed  by  miJk 
of  lime,  the  nitroprusside  being  kept  in  decided  excess.  A dark  red  solution  is  ob- 
tained, which  on  evaporation,  even  at  a gentle  heat,  deposits  prussian  blue.  When 
sufficiently  concentrated  the  solution  yields  crystals  of  a dark  red  colour,  and  of 
considerable  lustre.  The  crystals  belong  to  the  oblique  system.  They  have  been 
approximatively  measured  by  Prof.  Miller. 

Symbols : — a 100,  c 001,  m 1 10  ; there  are  besides  one  or  two  faces 
in  the  zone  c m c',  the  symbols  of  which  have  not  been  found. 

Cleavage  a very  perfect. 

Angles  between  normals  to  faces  approximately : — 


17L' 


ac  82  0 
ma  70  0 
mm'  40  0 


A NEW  CLASS  OF  SALTS. 


503 


The  values  of  cu  were  extremely  discordant.  In  the  best  crystals,  the  angle  between 
normals  to  cu  was  found  to  be  71°  41'. 

Nitroprusside  of  calcium  is  very  soluble  in  water,  and  in  its  behaviour  to  reagents 
is  exactly  the  same  as  the  soluble  nitroprussides  already  described.  By  the  mean  of 
two  experiments  the  crystallized  salt  lost  17‘85  per  cent,  of  water  in  the  water-bath 
at  212°. 

The  salt  was  analysed  by  fusion  with  nitrate  of  ammonia,  the  iron  and  lime  being 
determined  in  the  usual  way. 

13’29  grs.  gave  4*004  grs.  peroxide  of  iron  and  4*698  grs.  carbonate  of  lime. 

8*33  grs.  burned  with  chromate  of  lead  gave  6*56  grs.  carbonic  acid  and  0*82  water. 


Iron  . . . 

. . . 21*09 

5 

140 

Calculated. 

21*11 

Calcium 

. . . 14*14 

5 

100 

15*08 

Carbon  . . 

. . . 21*47 

24 

144 

21*71 

Hydrogen  . 

. . . 1*09 

5 

5 

0*75 

Nitrogen 

■ * '1 42*21 

r 210 

210-) 

41*35 

Oxygen  . . 

1 8 

64  J 

100*00 

663 

100*00 

It  will  be  seen  that  this  salt  belongs  to  the  class  which  has  dissolved  some  of  the 
cyanide  of  iron  resulting  from  its  partial  decomposition,  and  that  therefore  the  electro- 
positive metal  is  in  too  small  quantity.  Allowing  for  this  impurity,  which  cannot  be 
removed,  it  is  probable  that  the  pure  nitroprusside  of  calcium  has  the  formula 
Fcg  Cyi2  3NO,  Cag-f-SHO.  The  loss  of  water  in  the  water-bath  corresponds  to 
15  equivs.,  which  ought  to  have  given  the  loss  as  17  per  cent.  In  one  experiment 
it  lost  17*44  per  cent.,  in  another  18*26.  We  may  conclude  that  the  formula  of 
the  crystallized  salt  is  Fcg  Cy^g  3NO,  Ca5-}-20HO. 

Altered  Nitroprusside  of  Barium. 

22.  When  a solution  of  nitroprusside  of  barium  is  boiled,  it  deposits  a brown  pre- 
cipitate containing  both  iron  and  barium*.  The  solution  now  crystallizes  either  in 
pyramidal  or  in  prismatic  crystals,  that  is,  in  the  first  state  when  crystallized  slowly, 
in  the  second  when  deposited  quickly  from  a hot  solution.  It  is  now  found  that  the 
salt  is  inconstant  in  composition,  different  preparations  giving  very  discordant  results. 
The  salt  is  however  peculiarly  difficult  to  dry,  having  to  be  kept  in  the  water-bath  for 
days  before  it  ceases  to  lose  weight ; it  abstracts  water  when  dried  most  speedily  from 
the  atmosphere. 

It  is  found  that  the  carbon  is  increased  in  a marked  degree.  The  following  two 
specimens  were  made  at  different  times  and  analysed.  Analyses  I.  and  II.  were  made 

* The  barytes  used  in  decomposing  the  nitroprusside  of  copper  was  that  made  by  boiling  peroxide  of  man- 
ganese with  sulphuret  of  barium.  It  always  contains  a little  hyposulphite,  and  the  brown  precipitate  was 
found  to  contain  sulphate  of  barytes. 


3 T 2 


504 


DR.  PLAYFAIR  ON  THE  NITROFRUSSIDES, 


on  the  same  specimen,  but  crystallized  over  again  for  analysis  II.  No.  III.  is  on  a 
totally  different  specimen. 


I.  14'40  grs.  gave  8*62  grs.  sulphate  of  barytes  and  3' 12  grs.  oxide  of  iron. 

II.  15‘90  grs.  gave  1017  gi's.  sulphate  of  barytes  and  3‘68  grs.  oxide  of  iron. 

III.  14‘135  grs.  gave  8‘47  grs. sulphate  of  barytes  and  3 06  grs.  oxide  of  iron. 
The  combustions  were  made  with  chromate  of  lead. 

I.  11735  grs.  gave  7*730  grs.  carbonic  acid  and  T390  gr.  water. 

11.  lO'GlO  grs.  gave  7'145  grs.  carbonic  acid  and  07OO  gr.  water. 

III.  14'045  grs.  gave  8’800  grs.  carbonic  acid  and  r900  gr.  water. 


Iron  . , 

Barium  , 
Carbon 
Hydrogen 


I. 

II. 

III. 

t Crystallization. 

2nd  Crystallization, 

New  portion. 

. 15-16 

16-27 

14-76 

. 35-57 

37*59 

37*85 

. 17*96 

18-34 

17*08 

1-31 

0-73 

1-50 

But  a new  portion  of  barytes  salt  did  not  give  the  same  result;  the  portion  ana- 
lysed was  in  prismatic  crystals,  and  crystallized  twice. 


I.  1 1-65  grs.  gave  6-58  grs.  sulphate  of  barytes  and  2*49  grs.  oxide  of  iron. 

II.  17'22  grs.  gave  9‘83  grs.  sulphate  of  barytes  and  3*58  grs.  oxide  of  iron. 

I.  6'87  grs.  gave  3-87  grs.  carbonic  acid  and  0‘52  gr.  water. 

II.  13-62  grs.  gave  7'44  grs.  carbonic  acid  and  0-69  gr.  water. 


Iron 
Barium 
Carbon 
Hydrogen  . 


IV. 

V. 

1st  Crystallization. 

2nd  Crystallization. 

. . 14-96 

14-55 

. . 33-23 

33-60 

. . 15-41 

16-38 

. . 0-83 

0-55 

Another  portion,  in  flat  prismatic  crystals,  made  by  neutralizing  nitroprussic  acid 
with  carbonate  of  barytes,  gave  the  following  results : — 


12-33  grs.  gave  6-61  grs.  sulphate  of  barytes  and  2-42  grs.  peroxide  of  iron. 
6-60  grs.  gave  4-005  grs.  carbonic  acid  and  T040gr.  water. 


VI. 

Iron 13-73 

Barium 31-53 

Carbon 16-52 

Hydrogen 1 -75 


In  this  case  the  salt  lost  no  more  in  the  water-bath,  although  this  was  to  have  been 
expected  from  its  larger  quantity  of  hydrogen. 

In  all  these  cases  the  specimens  were  excellently  crystallized,  and  yet  there  is  a 


A NEW  CLASS  OF  SALTS. 


505 


greater  or  less  quantity  of  a foreign  substance  prevailing  in  all,  and  producing  results 
so  very  discordant.  In  the  first  two  portions  analysed  the  barium  is  to  the  carbon 
(37‘01  ; ]7'79)  almost  exactly  as  1 equiv. : 5|equivs.,  and  the  iron  is  to  the  carbon, 
sensibly  though  not  so  exactly,  in  the  same  proportion.  In  analysis  VI.,  the  iron  is 
to  the  carbon  as  28  : 33*7,  or  rather  more  than  1 : while  the  barium  is  to  the  carbon 

as  1 : 6.  Again,  in  analyses  IV.  and  V.,  the  iron  is  to  the  carbon  as  1 : 5,  and  the 
barium  to  the  same  element  1 : 5^. 

Finally,  it  will  be  seen  further  on  that  the  silver  salt  made  from  these  altered  salts 
of  barium  do  not  contain  this  excess  of  carbon.  The  filtrate  from  the  silver  salts 
yields  on  evaporation  and  incineration  a small  quantity  of  a black  ash,  but  the  quan- 
tity being  so  small  the  nature  of  the  substance  could  not  be  ascertained.  We  can 
scarcely  suppose  that  it  is  a ferrocyanide,  because  we  should  have  expected  to  have 
it  precipitated  by  nitrate  of  silver,  even  though  it  could  not  be  recognized  by  its  usual 
tests.  It  would  be  useless  without  further  information  to  speculate  upon  the  probable 
nature  of  the  impurity.  Sufficient  however  has  been  shown  to  prove  that  the  most 
complicated  results  may  attend  the  analysis  of  specimens  of  nitroprusside  of  barium 
prepared  from  solutions  which  have  been  heated  and  thus  partially  decomposed. 

Altered  Nitroprusside  of  Sodium. 

23.  The  previous  analyses  of  the  crystallized  nitroprussic  acid  and  of  the  nitro- 
prussides  of  ammonium  and  barium,  and  the  composition  of  the  silver  salts  prepared 
from  them,  show  a want  of  accordance  between  the  iron  in  the  electro-negative  con- 
stituent and  the  metal  in  the  electro- positive  one.  The  iron  in  all  these  cases  is 
about  half  a per  cent,  in  excess,  therefore  not  sufficient  to  be  considered  as  being  in 
atomic  proportion.  It  was  thought,  from  the  very  distinct  crystallization  of  the 
sodium  salt,  that  this  excess  might  not  accompany  it  if  prepared  from  the  respective 
silver  salts  of  the  above  compounds.  Accordingly  the  silver  salt  was  decomposed 
by  an  equivalent  quantity  of  hydrochloric  acid.  The  resulting  solution  was  neutral- 
ized with  carbonate  of  soda  and  crystallized.  Analyses  I.  and  II.  were  made  on  a 
salt  thus  prepared  from  crysfallized  nitroprusside  of  barium.  Analysis  III.  on  a salt 
similarly  made  from  nitroprusside  of  ammonia.  Again,  when  we  refer  to  the  action 
of  caustic  soda  on  the  nitroprussides,  it  was  obvious  that  by  using  a less  quantity  of 
the  alkali  than  sufficed  to  effect  the  complete  decomposition,  a nitroprusside  with  a 
similar  impurity  in  solution  was  to  be  expected. 

Analysis  IV.  was  made  on  a specimen  thus  prepared,  and  its  accuracy  is  confirmed 
by  a future  analysis  of  a silver  salt. 

J I.  13‘695  grs.  gave  3‘72  grs.  peroxide  of  iron. 

1 II.  20-93  grs.  gave  5-72  grs.  peroxide  of  iron  and  9*93  grs.  sulphate  of  soda. 

III.  15-35  grs.  gave  4-25  grs.  peroxide  of  iron  and  7*10  grs.  sulphate  of  soda. 

IV.  11-13  grs.  gave  3 07  g’l’s.  peroxide  of  iron  and  5-06  grs.  sulphate  of  soda. 

The  combustions  were  made  with  chromate  of  lead. 


506 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


II.  13‘34  grs.  gave  9’74  grs.  carbonic  acid  and  1*58  gr.  water. 

III.  14*475  grs.  gave  10*68  grs.  carbonic  acid  and  1*67  gr.  water. 

IV.  6*730  grs.  gave  5*33  grs.  carbonic  acid  and  1*01  gr.  water. 


From  barium  salt. 

From  ammonium 

By  action  of 

( 

A ^ 

salt. 

caustic  soda. 

I. 

II. 

III. 

IV. 

Iron  . . . 

19*00 

19*12 

19*38 

19*30 

Sodium  . . 

* . • 

15*37 

15*00 

14*72 

Carbon  . . 

• . • 

19*91 

20*12 

21*59 

Hydrogen.  . 

. . . 

1*31 

1*21 

1*65 

Nitrogen  . . ' 

Oxygen  . . J 

. . . . 

44*39 

44*29 

42*74 

100*00 

100*00 

100*00 

It  will  be  seen  from  these  analyses  that  the  excess  of  iron  still  remains,  and  this  is 
further  confirmed  by  silver  salts  again  made  from  them  and  analysed.  It  will  also 
be  observed  that  in  specimen  IV.  we  have  the  same  remarkable  increase  in  carbon  as 
observed  in  the  barium  salt ; the  sodium  is  to  the  carbon  as  I : 5^,  which  is  exactly 
the  proportion  found  in  the  latter  salt ; but  this  excess  of  carbon  does  not  go  down 
with  a silver  salt  made  from  it. 

Examination  of  the  Silver  Salts  made  from  the  altered  Nitroprussides, 

24.  To  save  unnecessary  repetition,  the  numerous  analyses  made  of  the  silver  salts 
are  here  brought  together,  although  it  might  have  been  more  distinct  to  have  intro- 
duced them  under  the  respective  salts  from  which  they  were  made.  The  reason  for 
converting  them  into  silver  salts  was,  that  from  the  high  atomie  weight  of  silver  and 
its  accuracy  of  determination,  the  atomic  accordance  or  disagreement  between  it  and 
the  iron  could  more  readily  be  perceived. 

Analyses  I.  II.  and  III.  were  made  on  three  different  preparations  of  silver  salt 
made  from  three  different  specimens  of  crystallized  nitroprussic  acid,  by  adding  the 
latter  to  nitrate  of  silver. 

Analysis  IV.  was  made  upon  a portion  of  II.  treated  on  sand-bath  with  strong 
nitric  acid  in  the  hope  of  dissolving  out  the  excess  of  iron.  A very  small  quantity  of 
iron  was  detected  in  solution  by  prusside  of  potassium. 

Analysis  V.  was  made  on  the  silver  salt  prepared  from  crystallized  nitroprusside 
of  ammonia. 

Analyses  VI.  and  VII.  from  silver  salt  precipitated  from  crystallized  nitroprusside 
of  barium,  which  contained  17‘96grs.  of  carbon,  or  in  which  the  barium  was  to  the 
carbon  as  1 : 5^. 

Analysis  VIII.  On  previous  silver  salt  digested  on  the  sand-bath  with  strong 
nitric  acid  to  dissolve  out  excess  of  iron. 

Analysis  IX.  On  silver  salt  made  from  the  crystallized  sodium  salt  (No.  2)  con- 
taining 19*91  grs.  carbon. 


A NEW  CLASS  OF  SALTS. 


507 


Analysis  X.  Silver  salt  prepared  from  sodium  salt  (No.  4)  containing  2 r59  carbon, 
or  in  which  the  sodium  was  to  the  carbon  as  I : 5^.  In  order  if  possible  to  remove 
the  excess  of  iron,  the  salt  was  first  precipitated  by  sulphate  of  copper  and  washed, 
the  copper  salt  was  now  decomposed  by  soda  and  crystallized,  and  the  silver  salt  was 
precipitated  from  this  newly-crystallized  portion. 

I.  19*605  grs.  gave  3’77  gTS.  peroxide  of  iron  and  12‘86  grs.  chloride  of  silver. 

II.  1 6*795  grs.  gave  3*24  grs.  peroxide  of  iron  and  1 0*94  grs.  chloride  of  silver. 

III.  ] 3*580  grs.  gave  2*60  grs.  peroxide  of  iron  and  8*79  grs.  chloride  of  silver. 

IV.  6*765  grs.  gave  1*35  gr.  peroxide  of  iron  and  4*355  grs.  chloride  of  silver. 

V.  14*68  grs.  gave  2*80  grs.  peroxide  of  iron  and  9*44  grs.  chloride  of  silver. 

r VI.  13*16  grs.  gave  2*43  grs.  peroxide  of  iron  and  8*535  grs.  chloride  of  silver. 

^ VII.  24*41  grs.  gave  4*54  grs.  peroxide  of  iron  and  15*79  grs.  chloride  of  silver. 

VIII.  15*21  grs.  gave  2*88  grs.  peroxide  of  iron  and  9*89  grs.  chloride  of  silver. 

IX.  13*60  grs.  gave  2*60  grs.  peroxide  of  iron  and  8*80  grs.  chloride  of  silver. 

X.  8*81  grs.  gave  1*69  gr.  peroxide  of  iron  and  5*59  grs.  chloride  of  silver. 

The  combustions  were  made  partly  with  chromate  of  lead,  partly  with  oxide  of 
copper. 

I.  12*05  grs.  gave  6*08  grs.  carbonic  acid  and  0*10  gr.  water. 

II.  12*195  grs.  gave  6*10  grs.  carbonic  acid  and  0*08  gr.  water. 

IV.  8*10  grs.  gave  4*03  grs.  carbonic  acid  and  0*09  gr.  water. 

V.  10*35  grs.  gave  5*13  grs.  carbonic  acid  and  0*21  gr.  water. 

VI.  14*52  grs.  gave  7T8  grs.  carbonic  acid  and  0*05  gr.  water. 

VIII.  9*56  grs.  gave  4*85  grs.  carbonic  acid  and  0*04  gr.  water. 

IX.  10*835  grs.  gave  5*50  grs.  carbonic  acid  and  0*10  gr.  water. 


( 

I. 

A 

II. 

1 

III. 

IV. 

V. 

( 

VI. 

A 

VII.  ^ 

VIII. 

IX. 

X. 

Mean. 

Iron 

13-46 

13-50 

13-40 

13-97 

13-35 

12-92 

13-01 

13-25 

13-38 

13-42 

13-36 

Silver  

. 49-42 

49-02 

48-71 

48-46 

49-50 

48-67 

48-69 

48-93 

48-70 

47-77 

48-78 

Carbon 

. 13-75 

13-64 

13-56 

13-43 

13-48 

13-82 

13-84 

13-64 

Hydrogen 

0-09 

0-07 

0-12 

0-22 

0-03 

0-04 

0-10 

0-09 

Nitrogen  "I 
Oxygen  / 

23-28 

23-77 

23-89 

23-50 

24-90 

23-96 

23-98 

24-13 

100-00 

100-00 

100-00 

100-00 

100-00 

lOO-OO 

100-00 

100-00 

If  we  assume  the  mean  iron,  13*36,  to  represent  the  true  quantity,  then  the  silver  to 
correspond  to  it  in  atomic  proportion  should  have  been  51*53,  whereas  there  is  only 
48*78.  Hence  there  is  0*72  of  iron  in  excess  over  the  equivalent  quantity  ; this  excess 
corresponds  to  ^th  of  an  equivalent.  Again,  supposing  the  carbon  to  be  in  the  same 
proportion  to  the  silver  as  in  the  nitroprussides,  there  should  have  been  13*0,  so  that 
there  is  an  excess  of  0*64.  The  excess  of  iron  and  of  carbon  is  therefore  almost 
exactly  as  1 equiv. : 4 equivs.,  or  viewing  the  carbon  as  representing  cyanogen  as  1:2. 
On  this  view  the  amount  of  impurity  in  the  silver  salt  is  2*10  per  cent.  Calculating 
the  mean  analysis  deprived  of  this  supposed  impurity,  we  have 


508 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


Theory  of  nitroprusside  of  silver. 


Iron  .... 

. 12-92 

13-01 

Silver  . . . 

. 49-81 

50-18 

Carbon . . . 

. 13-28 

13-38 

Hydrogen  . . 

Nitrogen ") 
Oxygen  J 

0-097 

. 23-02 

0-18 

23-25 

100-00 

100-00 

In  the  previous  calculation  the  cyanide  supposed  to  be  present  is  Fe  Cy2 ; this 
only  denotes  the  proportion  of  iron  to  the  cyanogen  ; it  is  possible  though  less  pro- 
bable that  it  might  be  2(Fe  Cy-fHCy).  In  this  case  we  might  suppose  the  analysed 
silver  salts  to  contain  this  cyanide  somewhat  in  the  following  proportion  : 7 equivs. 
nitroprusside  to  1 equiv.  of  the  supposed  cyanide.  On  this  supposition  the  calcu- 
lated and  actual  numbers  would  be  as  follows : — 

Iron  .... 

Calculated. 

. 13-*50 

Mean. 

13-36 

Silver  . . . 

. 49-26 

48-78 

Carbon  . . . 

. 13-76 

13-64 

Hydrogen  . . 

. 0-20 

0-09 

It  is  not  however  to  be  supposed  that  this  cyanide  is  present  as  a chemical  com- 
pound in  the  above  proportion,  as  the  differences  in  the  analyses  show  that  it  occurs 
in  varying  and  not  very  definite  proportions. 

It  would  indeed  appear  that  the  barium  and  sodium  nitroprusside  contained  a 
body  in  which  the  iron  and  cyanogen  are  in  the  same  proportion  as  in  ferrocyanogen 
(FeCy3).  But  as  the  silver  salt  precipitated  from  them  does  not  contain  an  excess 
of  carbon,  it  can  scarcely  be  supposed  that  this  would  not  be  precipitated.  But  in 
fact  there  are  no  data  further  than  the  mere  ultimate  analyses  upon  which  reasoning 
can  be  founded  with  regard  to  this  dissolved  and  combined  foreign  substance  in  the 
partially  decomposed  nitroprussides.  As  however  all  their  essential  characters  and 
their  crystalline  form  remain  altogether  unaltered,  we  cannot  view  the  foreign  sub- 
stances as  more  than  accidental. 

Section  IV. — Action  of  Caustic  Alkalies  on  the  Nitroprussides. 

25.  When  a dissolved  caustic  alkali,  such  as  potash  or  soda,  is  added  to  a solution 
of  a nitroprusside,  the  dark  red  colour  of  the  solution  changes  to  an  orange-yellow. 
If  both  solutions  have  been  moderately  dilute,  no  oxide  of  iron  is  precipitated,  nor  is 
ammonia  evolved.  The  addition  of  alcohol  to  the  orange-yellow  liquid  causes  the  pre- 
cipitation of  an  aqueous  solution  of  a new  salt.  This  salt  may  be  procured  in  a solid 
state  as  follows.  Nitroprusside  of  potassium  is  dissolved  in  water  and  double  its  volume 
of  alcohol  is  added.  Caustic  potash  is  now  added  to  this  solution,  and  a yellow  curdy 
precipitate  is  obtained.  This  precipitate  is  washed  with  alcohol  to  free  it  from  an 
excess  of  either  of  the  reagents,  but  it  is  almost  impossible  to  remove  the  last  traces. 


A NEW  CLASS  OF  SALTS. 


509 


The  salt  is  now  pressed  between  folds  of  bibulous  paper  and  dried  in  vacuo  over  sul- 
phuric acid.  It  may  be  called  nitroprusside  of  potassium  and  potash. 

This  salt  is  of  a bright  yellow  colour  and  of  crystalline  appearance.  It  is  very 
sparingly  soluble  in  alcohol,  but  very  soluble  in  water,  to  which  it  gives  a strong 
alkaline  reaction.  It  precipitates  salts  of  lead  of  a fine  yellow  colour  like  the  chro- 
mate of  lead.  Salts  of  iron  are  precipitated  of  a yellowish  brown,  and  salts  of  copper 
of  a brown  colour.  On  the  addition  of  an  acid,  the  excess  of  potash  is  removed  and 
nitroprusside  of  potassium  remains  in  solution ; the  salt  therefore  is  a compound  of  a 
nitroprusside  with  potash.  It  will  not  crystallize  in  vacuo,  its  solution  decomposing 
with  the  deposition  of  an  oxide  of  iron,  and  with  the  escape  of  a gas  which  commu- 
nicates a pink  colour  to  the  sulphuric  acid  used  for  the  evaporation  in  the  air-pump. 
The  salt  heated  in  a tube  evolves  nitric  oxide  and  ammonia,  and  leaves  a black  residue 
which  yields  to  water  an  alkaline  solution  of  a nitroprusside.  When  its  solution  in 
water  is  boiled,  complete  decomposition  takes  place,  a ferrocyanide,  oxide  of  iron, 
nitrite  and  oxalate  of  potash  being  produced. 

It  is  almost  impossible  to  obtain  it  free  from  uncombined  nitroprusside,  which  is 
observed  to  remain  in  solution  when  a salt  of  lead  is  added  to  it.  If  potash  in  excess 
be  used,  it  is  equally  difficult  to  remove  the  excess  by  washing.  The  analyses  there- 
fore give  only  approximative  results  ; they  were  made  in  the  usual  way  by  decomposing 
the  salt  with  fuming  sulphuric  acid. 

I.  17*350  grs.  gave  3'440grs.  peroxide  of  iron  and  14'32  grs.  sulphate  of  potash. 

II.  37*870  grs.  gave  7*345  grs.  peroxide  of  iron  and  30*53  grs.  sulphate  of  potash. 

The  combustions  were  made  with  chromate  of  lead. 

I.  14’075  grs.  gave  7*765  grs.  carbonic  acid  and  TO  15  gr.  water. 

II.  13*71  grs.  gave  7*490  grs.  carbonic  acid  and  0*985  gr.  water. 

The  samples  of  salt  analysed  were  made  at  different  times. 


I. 

II. 

Mean. 

Calculated. 

Iron .... 

13*87 

13*57 

13*72 

5 

140 

14*38 

Potassium . . 

37*00 

36*14 

36*57 

9 

351 

36*07 

Carbon  . . 

15*04 

14*89 

14*96 

24 

144 

14*79 

Hydrogen 

0*80 

0*79 

0*79 

8 

8 

0*82 

Nitrogen  "l 
Oxygen  / ’ 

33*29 

34*61 

33*96 

rl5 

1 15 

210-) 

120  J 

33*94 

100*00 

100*00 

] 00*00 

973 

100*00 

Hence  this  salt  differs  from  nitroprusside  of  potassium  by  containing  4 atoms  of 
potash  attached.  Its  formula  is  therefore  Peg  Cy^g  3NO  K5-l-4KO-}-8HO.  There  is 
little  doubt  that  it  might,  when  quite  free  from  nitroprusside,  contain  an  additional 
equivalent  of  potash. 

It  has  been  stated  that  a solution  of  this  salt  is  decomposed  on  boiling.  Oxide  of 
iron  falls  down,  nitrogen  escapes,  and  the  solution  is  now  found  to  contain  ferro- 
cyanide  of  potassium,  nitrite  of  potash  and  traces  of  oxalate  of  potash. 

3 u 


MDCCCXLIX. 


510 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


26.  The  products  of  transformation  were  determined  (1)  by  precipitating  the  ferro- 
cyanide  by  alcohol;  (2)  by  adding  nitrate  of  lime  to  precipitate  the  oxalate*,  which 
was  always  accompanied  by  a minute  quantity  of  a pink  compound  containing  cya- 
nogen and  iron  ; (3)  by  examining  the  liquid  which  remained,  and  was  found  to  evolve 
nitric  oxide  on  the  addition  of  an  acid.  It  gave  a precipitate  with  nitrate  of  silver, 
which,  though  sparingly  soluble  in  cold  water,  dissolved  in  hot  water  and  crystallized 
on  cooling;  13’25  grs.  of  the  crystalline  salt  thus  obtained,  treated  with  hydrochloric 
acid,  gave  12‘33  grs.  chloride  of  silver,  or  70'03  per  cent.  Nitrite  of  silver  (AgO,  NO^) 
contains  70T2  per  cent. 

In  examining  the  relative  quantities  of  these  products  of  transformation,  recourse 
was  first  had  to  the  yellow  salt  itself.  But  as  this  generally  contained  a little  nitro- 
prusside,  and  as  the  products  of  decomposition  varied  with  the  period  of  ebullition, 
on  account  of  the  slower  action  from  the  insufficient  quantity  of  alkali,  it  was  found 
more  accurate  to  examine  the  transformations  by  acting  upon  a solution  of  nitro- 
prusside  with  an  excess  of  alkali.  Without  therefore  giving  the  details  of  the  expe- 
riments on  the  yellow  salt  itself,  some  of  the  general  results  may  be  stated ; from 
these  it  will  be  seen  that  the  quantities  of  oxide  of  iron  and  of  prusside  produced  vary 
according  to  the  conditions  of  the  experiment,  principally  according  to  the  longer  or 
shorter  period  of  ebullition.  100  parts  of  the  yellow  salt  gave,  on  boiling  its  aqueous 
solution, — 

I.  II.  III.  IV.  V. 

Peroxide  of  iron  ....  3‘0  3*58  3’0  3’56  2‘71 

Ferrocyanide  of  potassium  . 60‘86  60‘59  59*48  68*83  64*50 

In  all  these  cases  there  was  more  or  less  nitroprusside  of  potassium  undecomposed. 
The  amount  of  oxalate  of  potash  found  in  solution  varied  from  0*97  to  1*5  per  cent. 

The  transformation  was  now  examined  in  the  following  manner.  A weighed  quan- 
tity of  a nitroprusside  was  dissolved  in  water  and  boiled,  caustic  potash  or  caustic 
soda  (according  as  the  nitroprusside  was  a salt  of  potassium  or  sodium)  being  added 
to  the  boiling  solution,  until  a drop  taken  out  gave,  after  being  neutralized,  no  purple 
colour  with  a sulphide.  The  precipitated  oxide  of  iron  was  now  collected  and 
weighed.  The  filtrate  was  precipitated  by  alcohol,  and  the  prusside  collected  and 
determined  on  a weighed  filter.  The  filtrate  was  now  neutralized  with  acetic  acid, 
and  chloride  of  ealcium  added,  but  the  oxalate  of  lime  was  generally  not  in  sufficient 
quantity  to  collect  and  weigh,  mere  traces  being  obtained.  It  was  now  attempted  to 
estimate  the  amount  of  nitrate  by  the  process  described  by  Nesbit  for  analysing 
nitrates'!'',  that  is,  by  converting  its  nitrogen  into  ammonia  by  zine  and  muriatic 
acid,  the  hydrogen  being  slowly  evolved.  The  ammonia  thus  formed  was  separated 

* To  prove  that  this  was  an  oxalate,  a portion  was  precipitated  hy  nitrate  of  lead  from  the  solution  after 
precipitation  hy  alcohol.  The  precipitate  was  of  a pink  colour,  and  was  now  decomjjosed  hy  sulphuretted 
hydrogen,  neutralized  hy  pure  carbonate  of  soda,  and  again  precipitated  as  a lead  salt,  which  was  now  quite 
white.  Calcined  with  nitrate  of  ammonia,  T660  gr.  gave  T250  gr.  oxide  of  lead,  or  75'3  per  cent.  Oxalate 
of  lead  contains  75 '5  per  cent. 

f Memoirs  of  Chemical  Society. 


A NEW  CLASS  OF  SALTS. 


511 


by  distillation  vvith  caustic  soda,  collected  in  muriatic  acid  and  determined  as  chlo- 
ride of  platinum  and  ammonia.  This  process  did  not  however  give  constant  results 
in  my  hands,  probably  from  the  difficulty  of  preventing  the  escape  of  nitric  oxide  on 
adding  an  acid  to  the  nitrite.  The  nitrite  was  therefore  determined  by  loss.  In  one 
case  only  did  I,  by  the  above  process,  obtain  a result  approaching  the  quantity  of 
nitrite  in  solution. 

17-24  grs.  of  nitroprusside  of  sodium  were  dissolved  in  water,  the  solution  was 
boiled  and  caustic  soda  added,  keeping  the  solution  distinctly  alkaline  after  ebullition 
had  continued  for  some  time.  It  yielded  0-92  gr.  peroxide  of  iron,  and  14‘85  grs. 
ferrocyanide  of  sodium  ; the  residual  liquid,  treated  according  to  Nesbit’s  plan,  only 
gave  2*57  grs.  platinum  salt. 

Iron  precipitated 3'73  per  cent. 

Iron  in  prusside 15’08  per  cent. 

18-81 

Hence  all  the  iron,  except  about  0-5  per  cent.,  is  found  in  the  oxide  of  iron  and  in 
the  prusside ; the  remainder  is  probably  in  the  minute  quantity  of  pink  salt  alluded 
to  above.  The  carbon  contained  in  the  prusside  amounts  to  20-3  ; so  that  the  total 
quantity  of  cyanogen  has  gone  down  in  that  form,  the  carbon  in  the  nitroprusside 
being  20-0  per  cent. 

It  will  be  seen  that  the  iron  precipitated  as  peroxide  of  iron  is  one-fourth  that  re- 
tained in  the  ferrocyanide.  The  following  equation  expresses  the  transformation : — 
2(Feg  Cyi2  3NO,  Nag)  +9NaO=:4(Fe2  Cyg  Na4)  +3NaO,  N03-1-Fe2  O3-I-3N. 

Or  expressed  in  another  way, — 

4 equivs.  ferrocyanide  of  sodium  . . . Fcg  Cy24Na4g 


3 equivs.  nitrite  of  soda Nag  Ng  O42 

1  equiv,  peroxide  of  iron Fe2  O 3 

3 equivs.  nitrogen Ng 


2  equivs.  nitroprusside+9  of  soda=Fe4o  Cy24Na49Ng  Ojg 
The  first  change  is  obviously  to  form  ferrocyanide  of  sodium,  6 equivs.  of  oxygen 
passing  over  to  the  nitrous  oxide;  this,  with  the  oxygen  in  the  latter,  would  make 
4 equivs,  nitrous  acid ; but  the  2 equivs.  of  iron  liberated  require  3 of  oxygen  to 
form  peroxide,  which  it  receives  at  the  expense  of  the  nitrous  acid,  leaving  therefore 
3 equivs.  of  that  acid  to  unite  with  soda,  the  remaining  3 equivs  of  nitrogen  escaping 
as  a gas.  During  the  ebullition  no  ammonia  can  be  detected,  either  by  smell  or  by 
turmeric  paper. 

Section  V. — Action  of  an  Alkaline  Sulphide  on  a Nitroprusside. 

27.  It  has  been  repeatedly  mentioned,  that  when  solutions  of  nitroprusside  of 
potassium  or  sodium  and  of  the  corresponding  sulphides  are  mixed  together,  the  most 
magnificent  purple  colour  is  produced.  This  colour  however  is  very  transitory  and 
cannot  be  preserved  in  an  aqueous  solution.  The  purple  or  blue  compound  may 

3  u 2 


512 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


however  be  obtained  in  a solid  state  when  alcoholic  solutions  of  the  two  salts  are 
employed.  In  order  to  obtain  it  in  this  state,  nitroprusside  of  sodium  is  dissolved  in 
the  smallest  possible  quantity  of  water,  and  to  this  solution  is  added  four  or  five  times 
its  bulk  of  alcohol.  An  alcoholic  solution  of  neutral  sulphide  of  sodium  (the  sulphide 
obtained  by  reducing-  the  sulphate  with  hydrogen)  is  now  added  to  the  alcoholic 
solution  of  nitroprusside,  the  addition  being  stopped  before  the  supernatant  liquid 
gives  a decidedly  black  reaction  on  lead  paper.  The  mixed  solutions  acquire  a 
magnificent  purple  blue  colour.  On  stirring  the  mixture,  an  aqueous  solution  of  the 
purple  compound  falls  down  in  oily  drops.  After  this  has  settled,  the  alcohol  is  de- 
canted, and  the  blue  solution  is  washed  repeatedly  and  quickly  with  alcohol  by  de- 
cantation. It  is  now,  as  rapidly  as  possible,  put  in  vacuo  over  sulphuric  acid,  when 
it  soon  parts  with  its  water  and  becomes  solid.  It  usually  dries  to  a dirty  green 
powder,  which  is  a mixture  of  the  purple  compound  with  the  products  of  its  decom- 
position. It  may  however,  though  this  is  rare,  dry  quite  unchanged  in  its  character, 
being  still  of  a fine  blue  colour  and  dissolving  entirely  in  water  with  all  its  magnifi- 
cent purple  blue  shade.  It  cannot  then  be  dried  in  the  water-bath,  where  it  quickly 
decomposes  and  becomes  green. 

The  following  analysis  was  made  on  two  portions  which  were  dried  in  the  air-pump, 
until  they  ceased  to  lose  weight  and  had  all  their  properties  unchanged.  They  were 
oxidized  by  nitrate  of  ammonia;  the  residue  was  dissolved  in  nitric  acid.  The  iron 
was  precipitated  as  peroxide,  the  sulphur  estimated  as  sulphate  of  barytes,  and  the 
soda  as  a sulphate. 

I.  14’210grs.  gave  3‘420  grs.  peroxide  of  iron,  5’710grs.  sulphate  of  barytes  and 
9'38  grs.  sulphate  of  soda. 

II.  8’99  grs.  gave  3*88  grs.  sulphate  of  barytes  and  6*62  grs.  sulphate  of  soda,  the  iron 
being  aceidentally  lost. 

The  combustion  was  made  by  chromate  of  lead,  peroxide  of  lead  being  used  to 
arrest  the  sulphurous  acid. 

I.  6‘20  grs.  gave  3-855  grs.  carbonic  acid  and  0-440  gr.  water. 

II.  10-565  grs.  gave  6-810  grs.  carbonic  acid  and  0-675  gr.  water. 


I. 

II. 

Mean. 

Iron  . . . 

. . 16-84 

16-84 

16-84* 

Sodium  . . 

. . 21-37 

23-84 

22-60 

Sulphur . . 

. . 5-51 

5-92 

5-71 

Carbon  . . 

. . 16-95 

17-58 

17-27 

Hydrogen  . 
Nitrogen  ) 

. . 0-78 

0-71 

0-74 

Oxygen  J ’ 

. . 38-55 

35-1 1 

36-84 

100-00 

100-00 

100-00 

* It  should  be  stated  that  in  many  analyses  of  this  compound  in  its  partially  decomposed  state,  the  most 
discordant  results  were  obtained.  The  two  analyses  here  adduced  were  made  on  the  only  specimens  which 
appeared  to  be  unchanged ; in  all  the  other  cases  the  compound  had  become  green  and  therefore  was  decom- 
posed, as  it  no  longer  dissolved  in  water  with  its  characteristic  purple  tint. 


A NEW  CLASS  OF  SALTS. 


513 


In  such  a variable  compound  as  this,  close  results  can  scarcely  be  looked  for  in 
two  analyses.  As  an  approximation,  however,  it  will  be  seen  that  the  iron  is  to  the 
sodium  as  5 ; 8,  and  to  the  sulphur  as  5 : 3. 

The  blue  unchanged  compound  gives  with  protosulphate  of  iron  a beautiful  pre- 
cipitate of  the  same  purple  blue  colour  as  itself,  but  this  is  decomposed  by  washing. 
With  salts  of  lead  it  gives  a brownish  yellow  precipitate,  with  salts  of  copper  a brown 
precipitate,  both  these  being  obviously  products  of  decomposition. 

28.  The  purple  blue  compound  dissolved  in  water  speedily  becomes  red,  and  when 
in  this  state,  a salt  of  lead  throws  down  a pinkish  red  precipitate.  This  red  solution 
however  soon  decomposes,  a brownish  precipitate  falling,  and  the  yellow  colour  due 
to  a prusside  being  seen  in  the  solution.  If  the  sulphide  originally  employed  con- 
tained sulphuretted  hydrogen,  a soluble  prussian  blue  is  also  found  in  the  liquid. 
During  these  changes,  ammonia,  hydrocyanic  acid,  and  a gas  possessing  the  proper- 
ties of  nitrogen  are  given  off.  In  fact,  on  mixing  the  solutions  of  sulphide  and  nitro- 
prusside,  it  is  difficult,  even  by  keeping  the  solutions  quite  cold,  to  prevent  the  form- 
ation of  a little  ammonia  and  escape  of  nitrogen.  The  solution  of  the  purple  com- 
pound in  water  decomposes  even  under  the  air-pump,  depositing  the  brown  precipi- 
tate, and  it  does  so  immediately  when  it  is  boiled. 

When  the  solution  is  filtered  from  the  brown  precipitate,  the  addition  of  alcohol 
separates  ferrocyanide  of  sodium.  The  alcoholic  filtrate  strikes  a blood-red  colour 
vdth  a persalt  of  iron,  and  with  sulphuric  acid  evolves  nitric  oxide,  which  is  immedi- 
ately rendered  sensible  by  a protosalt  of  iron,  a nitrite  being  thus  shown  to  be  in 
solution.  Ammonia  cannot  be  detected  in  the  solution,  neither  does  it  appear  to  any 
great  extent  when  the  transformation  takes  place  in  the  cold,  though  it  always  does 
so  when  ebullition  is  used  to  hasten  the  transformation.  It  therefore  appears  to  be 
the  product  of  an  after  action. 

The  brown  precipitate  is  first  to  be  examined.  It  is  found  to  consist  of  peroxide 
of  iron  and  sulphur,  the  latter  remaining  when  the  former  is  dissolved  out  by  an  acid. 
It  was  analysed  by  oxidation  with  nitromuriatic  acid.  7*21  grs.  gave  16‘90  grs. 
sulphate  of  barytes,  equal  to  2’33  grs.  of  sulphur,  and  4'22grs.  peroxide  of  iron,  the 
rest  being  water.  Hence  the  proportion  of  sulphur  to  iron  in  equivalents  is  nearly 
as  4:3  ; the  proportion  for  2‘33  sulphur  would  yield  3’0  iron,  while  2'95  was  found 
by  the  experiment. 

It  was  now  desirable  to  ascertain  what  proportion  of  iron  was  thrown  down  as 
ferrocyanide  and  how  much  remained  in  the  brown  precipitate.  For  this  purpose  a 
portion  of  a preparation,  which  had  become  green  by  standing  in  the  air-pump,  was 
first  analysed  in  order  to  ascertain  the  relative  proportion  of  its  constituents,  and  it 
was  then  dissolved  in  water  and  boiled. 

14*41  grs.  gave  6*93  grs.  sulphate  of  barytes,  17‘68grs.  gave  3*55  grs.  peroxide  of 
iron  and  10*00  grs.  sulphate  of  soda.  6*025  grs.  gave  3*31  grs.  carbonic  acid  and 


514 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


0*820  gr.  water.  Hence  this  changed  purple  compound,  before  complete  transform- 
ation, contained  in  100  parts, — 

Iron  . . 

Sodium  . 

Sulphnr. 

Carbon  . 

Hydrogen 

Nitrogen  ") 

Oxygen  J 

100*00 

11*31  grs.  were  now  boiled  in  water,  and  0*94  gr.  of  the  brown  precipitate  was 
obtained  by  filtration,  and  5*90  grs.  of  prusside  of  sodium  were  precipitated  by 
alcohol.  Hence  of  the  total  quantity  of  1*58  gr.  of  iron  present  1*08  gr.  was  found  in 
the  ferrocyanide,  the  remainder  being  in  the  brown  precipitate.  As  the  ferrocyanide 
of  sodium  is  of  constant  composition,  which  the  brown  mixture  is  not,  the  iron  in  the 
latter  is  here  estimated  by  loss  and  would  amount  to  0*50  gr.  The  proportion  in 
equivalents  is  nearly,  though  not  exactly,  as  7 : 3,  which  would  have  made  the  iron  in 
the  brown  precipitate  0*46  gr.  instead  of  0*50  gr.. 

Taking  these  proportions  as  leading  to  a general  view  of  the  transformation,  it 
may  be  expressed  by  the  following  equation : — 

2(Fe5  Cyi2  3NO-l-8Na-}-3S)-l-2HO=7(Na2  Fe  Cy3)-)-(Na,  Cy  S2)H-(Na  O,  NO3) 
+Fe3  04-1-84 -l-2HCy  -|-2N. 

The  only  point  in  which  this  transformation  does  not  agree  with  experiment,  is  in 
the  supposed  production  of  ferrous-ferric  oxide,  whereas,  when  the  brown  precipitate 
is  washed  with  acid,  only  peroxide  of  iron  unaccompanied  by  protoxide  of  iron  passes 
through.  It  is  therefore  probable  that  the  oxidation  of  this  oxide  may  give  rise  to 
the  small  quantity  of  ammonia  observed,  the  oxygen  from  decomposed  water  uniting 
with  it,  and  the  nascent  hydrogen  with  nitrogen  to  form  ammonia.  Allowing  this  to 
be  the  explanation  of  the  disagreement  with  experiment,  the  following  scheme  may 
render  the  above  equation  more  immediately  intelligible.  Two  equivalents  of  the 
blue  compound  with  2 equivs.  of  water,  by  boiling,  are  resolved  into — 

7 equivs.  ferrocyanide  of  sodium. 

1 equiv.  sulphocyanide  of  sodium. 

1 equiv.  nitrite  of  soda. 

1 equiv.  oxide  of  iron  (Fe0-1-Fe203). 

4 equivs.  sulphur. 

2 equivs.  hydrocyanic  acid. 

2 equivs.  nitrogen. 


18*33 

6*59 

14*98 

1*51 

44*54 


A NEW  CLASS  OF  SALTS. 


515 


And  probably  the  ferroso-ferric  oxide  is  transformed  at  the  expense  of  the  oxyg^en  of 
water  into  ferric  oxide,  the  hydrogen  forming  ammonia  with  nitrogen, 

6Fe0+3H0+N=3Fe203+NH3. 

29.  In  giving  the  above  equation,  the  blue  sulphur  compound  was  supposed  to 
consist  of  nitroprusside  of  sodium  with  3 equivs.  of  sulphuret  of  sodium  attached. 
The  following  calculation  shows  that  this  is  an  expression  of  the  analysis  : — 


Calculated. 

Mean  experiment. 

5 Iron  . 

. 140 

17-36 

16-84 

8 Sodium  . 

. 186 

23-07 

22-60 

24  Carbon  . 

. 144 

17-86 

17-27 

3 Sulphur  . 

48 

5-95 

5-71 

6 Hydrogen 

6 

0-74 

0-74 

15  Nitrogen  . 

. 210') 

35-02 

36-84 

9 Oxygen  . 

. 72  j 

806 

100-00 

100-00 

The  approximation  is  sufficiently  near  when  the  difficulty  of  getting  the  substance 
in  at  all  a stable  state  is  considered.  Two  views  might  be  taken  of  the  constitution 
of  this  singular  compound  (1),  that  it  is  nitroprusside  of  sodium  with  3 equivs.  of 
sulphuret  of  sodium  attached — 

Fcg  Cyi2  3N(),  5Na+3NaS+6HO  ; 

but  this  would  scarcely  account  for  its  extreme  facility  of  decomposition  ; it  may 
therefore  be  supposed  that  caustic  soda  is  attached  to  the  salt,  as  we  have  seen  that 
it  can  be,  in  studying  the  action  of  alkalies  on  the  nitroprussides,  and  that  the  sulphur 
has  taken  the  place  of  the  oxygen,  thus  ; — 

Fe5Cyi2  3NS,  5Na+3NaO+6HO. 

Either  of  these  formulae  would  suit  the  analysis  ; in  support  of  the  latter  may  be 
adduced  the  fact  observed  by  Gregory,  that  sulphuret  of  nitrogen  in  the  presence 
of  caustic  alkalies  acquires  a deep  transitory  amethyst  colour,  which,  on  disappear- 
ing, evolved  ammonia,  a description  exactly  accordant  with  the  present  case. 

Action  of  Sulphuretted  Hydrogen  on  the  Nitroprussides. 

30.  Sulphuretted  hydrogen  decomposes  the  soluble  nitroprussides.  The  products 
of  transformation  are  most  conveniently  obtained  in  the  following  way: — Nitro- 
prusside of  sodium  is  dissolved  in  the  smallest  possible  quantity  of  cold  water,  and 
three  or  four  times  its  volume  of  alcohol  is  added  to  the  solution.  Sulphuretted 
hydrogen  is  now  passed  through  this  alcoholic  solution.  Sulphur,  prussian  blue, 
and  ferrocyanide  of  sodium,  are  very  gradually  precipitated ; the  action,  however,  is 
very  slow,  and  must  be  long  continued.  The  alcoholic  solution  is  now  of  a reddish 
olive-brown  colour.  When  the  sulphuretted  hydrogen  has  ceased  to  act,  this  super- 
natant brownish  liquid  gives  no  coloration  when  mixed  with  an  alkaline  sulphide. 


516 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES, 


If  allowed  to  stand  for  a few  hours,  it  deposits  a little  of  the  precipitates  which  it  held 
in  solution.  After  this  the  brown  solution  is  found  to  contain  neither  ferrocyanide 
nor  nitroprusside  of  sodium  ; a persalt  of  iron  is  slightly  deepened  in  colour  when 
mixed  with  it,  showing  the  presence  of  a mere  trace  of  a sulphocyanide.  When  this 
reddish-brown  solution  is  evaporated  in  the  water-bath,  it  deposits  oxide  of  iron  and 
sulphur,  and  becomes  decomposed.  Evaporated  in  vacuo  over  sulphuric  acid  it  de- 
posits, when  nearly  dry,  black  crystalline  needles,  but  these  seem  to  be  a product  of 
decomposition,  and  are  mixed  with  oxide  of  iron  and  other  substances  ; attempts  were 
therefore  made  to  ascertain  the  composition  of  the  original  substance  by  precipitating 
its  solution  by  metallic  salts.  Bichloride  of  mercury  produces  a brown  precipitate, 
sulphate  of  copper  a pinkish  brown,  and  nitrate  of  silver  a black  precipitate.  But 
these  were  obviously  products  of  decomposition,  for  during  the  precipitation  nitric 
oxide  is  abundantly  evolved.  This  is  especially  the  case  in  the  precipitate  with  silver. 
If  that  precipitate,  after  being  washed,  be  now  mixed  with  a small  quantity  of  hydro- 
chloric acid  to  take  up  the  silver,  sulphuretted  hydrogen  is  evolved,  protochloride  of 
iron  and  abundance  of  sulphocyanic  acid  are  now  found  in  solution ; the  first  is  re- 
cognized by  the  prussian  blue  formed  on  adding  red  prusside  of  potassium,  the  second 
by  the  blood-red  colour  which  it  strikes  with  perchloride  of  iron.  When  nitrate  of 
silver  is  added  to  the  red-brown  solution,  the  black  precipitate  already  alluded  to 
falls  down,  but  at  the  same  time  the  supernatant  liquor  had  a reddish  brown  colour ; 
on  examining  this  it  was  found  to  contain  a persalt  and  protosalt  of  iron,  the  dark 
coloration  being  due  to  the  escaping  nitric  oxide.  The  amount  of  sulphur  precipi- 
tated during  the  passage  of  sulphuretted  hydrogen  through  the  nitroprusside  is  about 
17  per  cent.;  the  amount  of  ferrocyanide  of  sodium  and  of  prussian  blue  has  been 
found  to  vary  much. 

From  the  difiiculty  of  obtaining  the  products  of  transformation  in  a pure  state,  I 
have  not  yet  been  able  to  make  direct  quantitative  examinations  of  the  various  sub- 
stances formed ; it  is  therefore  impossible  to  express  the  transformation  in  the  form 
of  an  equation.  From  some  experiments  now  in  progress,  I trust,  however,  to  over- 
come those  difficulties  which  have  prevented  the  completion  of  this  study  in  time  for 
the  presentation  of  this  paper. 

On  the  Constitution  of  the  Nitroprussides. 

31.  In  the  preceding  part  of  the  paper  the  analyses  of  the  nitroprussides  led  to  the 
extremely  complicated  formula  Feg  C24  O3  Rj.  This  formula  was  a priori  very 
improbable,  and  naturally  led  to  the  belief  that  an  error  in  the  estimation  of  the 
carbon  forced  its  adoption.  In  fact,  if  25  instead  of  24  equivs.  of  carbon  were  pre- 
sent, the  formula  would  resolve  itself  into  the  much  simpler  expression  Fe2  Ng  O R2. 
It  is  therefore  important  to  review  the  evidence,  in  order  to  see  whether  the  simple  pro- 
portion of  iron  to  carbon,  1 ; 5,  might  be  derived  from  it.  The  following  table  exhibits 
the  proportion  of  iron  and  carbon  found  in  the  analyses  of  the  respective  salts : — 


A NEW  CLASS  OF  SALTS. 


517 


Name  of  salt. 

Number  of  analyses 
furnishing  the  mean. 

Quantity  of  iron. 
Mean. 

Quantity  of  carbon. 
Mean. 

Atomic  relation  of 
iron  to  carbon. 

Nitroprusside  of  sodium  

9 

19-54 

20-03 

28 

: 28-7 

Nitroprusside  of  potassium  

5 

19-05 

19-63 

28 

: 28-8 

Nitroprusside  of  ammonium 

3 

22-08 

22-69 

28 

: 28-7 

Nitroprusside  of  silver  

4 

13-03 

13-29 

28 

: 28-5 

Nitroprusside  of  copper  

4 

20-43 

21-25 

28 

: 29-0 

Nitroprusside  of  iron 

3 

19-09 

19-96 

28 

: 29-2 

Nitroprusside  of  zinc 

1 

20-07 

20-53 

28 

: 28-6 

Nitroprusside  of  calcium  

1 

21-09 

21-47 

28 

: 28-5 

Nitroprusside  of  barium  

2 

14-10 

14-98 

28 

: 29-7 

Nitroprussic  acid  

3 

23-80 

24-80 

28 

: 29-1 

Mean  of  the  whole 

35 

192-30 

198-63 

28 

: 28-9 

Now  the  proportion  of  1 equiv.  of  iron  to  5 equivs.  of  carbon  would  require  the 
proportion  28  ; 30.  This  difference  is  too  great-4o  be  due  to  any  errors  of  observa- 
tion, especially  when  it  is  remembered  that  these,  in  the  case  of  a body  containing 
much  nitrogen,  tend  to  increase  and  not  to  diminish  the  apparent  quantity  of  carbon. 
The  actual  proportion  found,  28  : 28’9,  indicates,  in  equivalents,  5 equivs.  iron  to 
24  equivs.  carbon  ; this  proportion  would  require  28  : 28’8  ; the  slight  excess  found  is 
in  the  direction  of  the  known  errors  of  observation. 

These  considerations  forced  the  adoption  of  the  complex  formula  given  above.  It 
will  also  be  seen,  from  an  examination  of  the  analytical  details,  that  the  quantity  of 
nitrogen  corresponds  to  6 equivs.  for  every  10  equivs.  of  carbon,  or  15  equivs.  for  the 
24  equivs.  of  carbon  required  by  the  formula.  As  12  of  these  are  in  the  state  of 
cyanogen,  as  shown  both  by  the  transformation  of  the  nitroprussides  by  alkalies  and 
by  sulphides,  the  remaining  3 equivs.  must  be  in  the  form  of  an  oxide  of  nitrogen. 
But  the  loss  on  the  analyses  does  not  admit  the  supposition  that  the  oxide  is  nitric 
oxide,  as  might  have  been  supposed,  neither  do  the  transformations  countenance  this 
idea.  The  oxygen  is  in  the  proportion  of  3 equivs.  for  every  3 equivs.  of  nitrogen ; 
the  nitrogen  not  present  as  cyanogen  must  exist  as  nitrous  oxide.  This  is  unusual, 
and  its  functions  must  therefore  be  inquired  into.  It  will  at  once  be  seen  that  if 
nitrons  oxide  is  supposed  to  substitute  and  play  the  part  of  cyanogen,  the  iron  and 
the  non-electro-negative  bodies  with  which  it  is  associated  are  present  in  the  same 
proportion  as  in  the  hypothetical  radical  ferrocyanogen  ; 5 equivs.  ferrocyanogen  have 
the  formula  Fcg  Cyis;  1 equiv.  of  nitro-ferrocyanogen  has  the  formula  Fcs  Cyi2  3NO. 
The  nitroprussides  are  therefore  supposed  to  contain  a ferrocyanogen  in  which  3 equivs. 
of  cyanogen  are  substituted  by  3 equivs.  of  nitrous  oxide. 

32.  But  the  proportion  of  the  electro-positive  element  in  the  nitroprussides  is  less 
than  that  existing  either  in  the  ferrocyanides  or  ferridcyanides.  Liebig  supposes  these 
two  latter  compounds  to  differ  by  containing  different  radicals,  one  being  twice  the 
atomic  weight  of  the  other.  It  would  be  equally  instructive  to  suppose  that  they 
both  contain  the  same  radical,  but  that,  as  in  the  case  of  the  different  phosphoric 
acids,  one  is  quadribasic,  while  the  other  is  tribasic. 

3 X 


MDCCCXLIX. 


518 


DR.  PLAYFAIR  ON  THE  NITROPRUSSIDES,  A NEW  CLASS  OF  SALTS. 


Quadribasic  prussides,  Fe2  Cyg+4R,  formula  of  ferrocyanides. 

Tribasic  prussides  , . . Fe2Cyg+3R,  formula  of  ferridcyanides. 

Bibasic  prussides  ....  Fe2  CygH-2R,  formula  of  undescribed  compounds. 

With  regard  to  the  last  class,  its  existence  must  be  yet  considered  hypothetical,  but 
in  searching  for  it,  I have  received  sufficient  encouragement  to  enable  me  to  hope 
that  I shall  very  shortly  be  able  to  establish  it.  Without  presenting  the  analytical 
evidence  to  this  effect,  it  can  only  be  adduced  as  a probable  hypothesis  to  explain 
the  nitroprussides.  The  latter  class  of  salts  may  be  supposed  to  correspond  to  a bi- 
basic class  of  prussides  in  which  part  of  the  cyanogen  is  replaced  by  nitrous  oxide. 
Thus  5(Fe  Cyg-I-R)  = Fcg  Cyig  + 5R  correspond  to  1 equiv.  of  a nitroprusside, 
Fcg  Cyi2  3NO-I-5R.  The  great  approximation  of  the  latter  formula  to  the  more 
simple  expression  Fe2  Cyg  NO-{-2R,  renders  it  singular  that  the  small  deficiency  of 
carbon  refuses  to  allow  the  formula  to  be  thus  expressed.  In  such  a case  this  sup- 
posed bibasic  prusside  and  the  nitroprusside  would  stand  in  a very  simple  relation  : 

Fe2Cyg^  +2R, 

Fe2  CygNO-l-2R. 

The  complicated  formula  required  by  the  analyses  of  all  the  nitroprussides  might 
be  resolved  into  2(Fe2  Cyg  NO-{-2R)H-(Fe  Cy2  NO-fR),  in  which  the  latter  member 
is  constituted  on  the  same  type,  but  more  cyanogen  is  displaced  by  the  nitrous  oxide. 
It  will  not  excite  surprise,  after  what  has  been  learned  in  the  previous  inquiry  as  to 
the  obstinate  manner  in  which  the  nitroprussides  unite  with  cyanides  from  which  they 
are  not  removable  by  any  means  tried,  that  a salt  constituted  on  the  same  type  should 
unite  with  the  true  nitroprussides  and  form  an  integrant  conjugate  compound  which 
is  not  broken  up  by  crystallization.  It  appears  therefore  very  probable  that  the  true 
formula  of  the  nitroprussides  may  in  reality  be  Fe2  Cyg  NO-(-2R,  and  that  further  re- 
search may  eliminate  this  compound.  Hitherto  this  has  not  been  done,  and  the  only 
formula  which  correctly  expresses  the  analysis  is  Feg  Cyi2  3NO-1-5R,  which  on  theo- 
retical, but  on  no  other  grounds,  may  be  resolved  into 

2(Fe2  Cyg  NO-f  2R)-l-(Fe  CygNO+R). 

I trust  soon  to  be  able  to  present  to  the  Society  another  memoir  on  the  prussides, 
which  will  confirm  experimentally  some  of  the  views  theoretically  supported  in  the 
present  communication;  but  at  present  I submit  the  previous  results  with  a view  of 
drawing  attention  to  this  interesting  class  of  salts,  and  with  a perfect  conviction  that 
future  research  will  simplify  and  explain  the  remarkably  complex  and  unsatisfactory 
formulse  which  I have  been  obliged  to  adopt,  without  believing  them  to  be  the 
correct  expression  of  the  constitution  of  the  salts. 


INDEX 


TO  THE 


PHILOSOPHICAL  TRANSACTIONS 

FOR  THE  YEAR  1849. 


A. 

Acidity  of  the  Urine,  on  the  variations  of,  235. 
Anatomy  and  affinities  of  the  Medusce,  413. 
Annelides,  structure  of  the  liver  in,  110. 
Antimony,  crystalline  polarity  of,  13. 

Arachnidans,  structure  of  the  liver  in,  116. 
Arsenic,  crystalline  polarity  of,  17. 

Atlantic,  lines  of  Magnetic  Declination  in,  173. 


B. 

Bakerian  Lecture,  1. 

Barlow  (W.  H.  Esq.).  On  the  Spontaneous  Electrical  Currents  observed  in  the  Wires  of  the 
Electric  Telegraph,  61. 

Birds,  structure  of  the  liver  in,  123. 

Bismuth,  crystalline  polarity  of,  2. 

Brodie  (B.  C.,  Esq.).  Investigation  on  the  Chemical  Nature  of  Wax,  91. 

Brom-orcin,  397. 

Bryozoon,  structure  of  the  liver  in,  109. 

C. 

Carapace  of  Chelonian  Reptiles,  development  and  homologies  of,  151. 

Chelonian  Reptiles,  on  the  development  and  homologies  of  the  carapace  and  plastron  of,  151 ; 
definition  of  the  component  parts  of  the  Carapace,  152;  of  the  Plastron,  153.  Comparison 
of  the  thoracic  segment  of  the  Tortoise  with  that  of  the  Bird,  157 — and  with  that  of  the 
Crocodile,  158.  Embryonic  condition  and  development  of  the  Carapace,  159;  of  the  Plas- 
tron, 163.  Dermal  nature  and  seat  of  development  of  the  neural,  costal  and  lateral  plates,  and 
of  certain  parts  of  the  Plastron,  164.  Summary,  165.  Supplement  on  Professor  Rathke’s 
conclusions,  166. 


3x2 


520 


INDEX. 


Chlor-melal,  95. 

Contributions  to  Terrestrial  Magnetism,  No.  IX.,  173. 

Crustaceans,  structure  of  the  liver  in,  115. 

Crystalline  polarity  of  bismuth,  2;  of  antimony,  13;  of  arsenic,  17. 

D. 

Dalrymple  (John,  Esq.).  Description  of  an  infusory  animalcule  allied  to  Notommata,  331. 
Dasyurus  ursinus,  on  the  dental  tissues  of,  408. 

Declination  {magnetic)  in  the  Atlantic,  173. 

Dental  tissues  of  the  Marsupial  Animals,  structure  of,  403. 

Didelphis  virginiana,  on  the  dental  tissues  of,  410. 

E. 

Echinodermata,  structure  of  the  liver  in,  109. 

Electrical  currents  (spontaneous)  observed  in  the  wires  of  the  electric  telegraph,  61. 

Electricity , Experimental  Researches  in.  Twenty-second  Series.  On  the  crystalline  polarity  of 
bismuth  and  other  bodies,  and  on  its  relation  to  the  magnetic  form  of  force,  1,  19.  Crystal- 
line polarity  of  bismuth,  2 ; of  antimony,  13  ; of  arsenic,  17.  Crystalline  condition  of  various 
bodies,  19.  Magne-crystallic  force,  22. 

Embryonic  condition  of  carapace  and  plastron  of  Chelonian  Reptiles,  158,  159. 

F. 

Faraday  (Dr.).  Experimental  Researches  in  Electricity.  Twenty-second  Series,  1,  19. 

Fish  [Ganoid  and  Placoid),  on  the  microscopic  structure  of  the  scales  and  dermal  teeth  of,  435. 
structure  of  the  liver  in,  118. 


G. 


Ganglia  and  nerves  of  the  Heart,  43. 

Ganoid  and  Placoid  Fish,  on  the  structure  of  the  scales  and  dermal  teeth  of,  435. 

Gases,  on  the  Motion  of,  349. 

Glaisher  (James,  Esq.).  On  the  reduction  of  the  Thermometrical  Observations  made  at  the 
Apartments  of  the  Royal  Society,  from  the  years  1774  to  1781,  and  from  the  years  1787  to 
1843,  307. 

Graham  (Thomas,  Esq.).  On  the  Motion  of  Gases.  Part  II.,  349. 

Grove  (W.  R.,  Esq.).  On  the  effect  of  Surrounding  Media  on  Voltaic  Ignition,  49. 

Gyrophora  pustidata,  analysis  of,  393. 


H. 

Heart,  on  the  ganglia  and  nerves  of  the,  43. 

Huxley  (Thomas  Henry,  Esq.).  On  the  Antomy  and  Affinities  of  the  Medusse,  413. 
Hylceosaurus,  on  the  osteology  of,  271. 

Hypsiprymnus  minor  and  penicillatus,  on  the  dental  tissues  of,  406. 


INDEX. 


5‘21 


I. 

Iguanodon,  notes  on  the  vertebral  column  of,  285. 

, osteology  of,  271.  Angular  bone  of  lower  jaw,  272.  Vertebral  column,  272.  Pectoral 

arch,  277.  Restoration  of  pectoral  arch,  279.  Humerus,  280.  Hinder  extremities,  282. 
Infusory  animalcule,  description  of,  331. 

Insects,  structure  of  the  liver  in,  113. 


J. 

Jones  (Dr.  C.  Handfield.).  On  the  Structure  and  Development  of  the  Liver,  109. 

Jones  (Dr.  H.  Bence.).  Contributions  to  the  Chemistry  of  the  Urine.  Paper  III.,  235. 

L. 

Lecanora  tartarea,  analysis  of,  396. 

Lee  (Dr.  Robert).  On  the  Nerves  and  Ganglia  of  the  Heart,  43. 

Lichens,  on  the  pi’oximate  principles  of,  393.  Gyrophora pustulata,  393.  Lecanora  tartarea,  396. 

Brom-orcin,  397.  Quintonitrated  erythromannite,  399. 

Liver,  on  the  structure  and  development  of,  109;  in  the  Bi’yozoon  Polype,  109;  in  the  Echino- 
dermata,  109;  in  the  Annelides,  110;  in  Insects,  113;  in  Crustaceans,  115;  in  Arachnidans, 
116;  in  Mollusca,  116;  in  Fishes,  118;  in  Reptilia,  122;  in  Birds,  123;  in  Mammalia,  124; 
development,  129. 


M. 

Macropus  giganteus,  on  the  dental  tissues  of,  404. 

Magnecrystallic  force,  nature  of,  22. 

Magnetic  declination,  lines  of,  in  the  Atlantic,  173. 

Magnetism,  7Vrre?5^na/,  Contributions  to.  No.  IX.  173.  Introduction,  173.  Observations  employed 
— A. Sea  observations  uncorrected  for  the  ship’s  magnetism,  175;  B.  Sea  observations  corrected 
for  the  ship’s  magnetism,  176.  Discusson  of  the  correctioins  for  the  ship’s  magnetism,  177. 
Arrangement  of  the  observations,  195.  Table  of  the  declination  in  1840  at  the  intersection 
of  every  5°  of  latitude  and  longitude,  202.  Table  of  secular  change,  203.  Comparison  with 
M.  Gauss’s  general  theory,  204.  General  table  of  the  observations  employed  in  the  Map, 
arranged  according  to  latitude  and  longitude,  207. 

Mammalia,  structure  of  the  liver  in,  124. 

Mantell  (Dr.  G.  A.).  Additional  observations  on  the  Osteology  of  the  Iguanodon  and  Ilylaso- 
saurus,  271. 

Marsupial  animals,  on  the  dental  tissues  of,  and  more  particularly  of  the  enamel,  403. 

Melen,  99. 

Melissin,  93, — Melissic  acid,  91. 

Melville  (Dr.  A.  G.).  Notes  on  the  Vertebral  Column  of  the  Iguanodon,  285. 

Meteorology  of  the  Lake  Districts  of  Cumberland  and  Westmoreland,  73,  319. 

Mollusca,  structure  of  the  liver  in,  116. 

Monostomatce,  anatomy  of,  413. 

Myricin,  91 ; distillation  of,  98;  palmitic  acid  from  saponification  and  distillation  of,  96,  98. 


522 


INDEX. 


N. 

Nitroprussides,  a Nevj  Class  of  Salts,  on  the.  Section  I.  477.  Section  II.  General  remarks  on 
the  Nitroprussides,  485.  Nitroprussic  acid,  486.  Nitroprusside  of  sodium,  487  ; of  potas- 
sium, 490 ; of  barium,  492  ; of  silver,  493 ; of  copper,  495  ; of  iron,  496 ; of  zinc,  497.  Sec- 
tion III.  On  changes  in  solutions  of  Nitroprussides,  498.  Section  IV.  On  the  action  of 
caustic  alkalies  in  nitroprussides,  508.  Section  V.  Action  of  an  Alkaline  Sulphuride  on  a 
Nitroprusside,  511.  Action  of  sulphuretted  hydrogen  on  nitroprussides,  513.  On  the  con- 
stitution of  the  nitroprussides,  516. 

Notommata,  description  of  an  infusory  animalcule  allied  to,  331. 

O. 

Osteology  of  Iguanodon  and  Hylfeosaurus,  271. 

Owen  (Professor).  On  the  Development  and  Homologies  of  the  Carapace  and  Plastron  of  the 
Chelonian  Reptiles,  151. 

P. 

Palmitic  acid,  96. 

Petaurus  taguanoides  and  sciureus,  on  the  dentinal  tissues  of,  408. 

Phalangista  vulpina,  on  the  dentinal  tissues  of,  407. 

Phascolomys  Wombat,  on  the  dentinal  tissues  of,  406. 

Placoid  and  Ganoid  Fish,  on  the  structure  of  the  scales  and  dermal  teeth  of,  435. 

Playfair  (Dr.  Lyon).  On  the  Nitroprussides,  a New  Class  of  Salts,  477. 

Potass  (caustic),  its  influence  on  the  acidity  of  the  urine,  261. 

Q. 

Qumto-nitrated  erythromannite,  399. 

R. 

Pain,  fall  of,  at  various  heights  above  the  earth’s  surface,  13,  319. 

Reptilia,  structure  of  the  liver  in,  122. 

Rhissostomidce,  anatomy  of,  413. 

S. 

Sabine  (Lieut.-Colonel).  Contributions  to  Terrestrial  Magnetism,  No.  IX.  173. 

Salts,  a new  class  of,  the  nitroprussides,  477. 

Sten HOUSE  (Dr.  John).  Examination  of  the  proximate  Principles  of  some  of  the  Lichens,  393. 
Sulphate  of  Iron,  magnecrystallic  condition  of,  37. 

Sulphates,  variation  of,  in  urine,  252. 

T. 

Tartaric  acid  and  tartrate  of  potash,  their  influence  on  the  acidity  of  the  urine,  261. 

Terrestrial  magnetism.  Contributions  to,  No.  IX.  173. 


INDEX. 


523 


Thermometrical  Observations  made  at  the  Apartments  of  the  Royal  Society,  reduction  of,  307. 

Thylacinus  cynocephalus,  on  the  dental  tissues  of,  409. 

Tomes  (John,  Esq.).  On  the  Structure  of  the  Dental  Tissues  of  Marsupial  Animals,  and  more 
particularly  of  the  Enamel,  403. 

Tongue,  minute  structure  of  the  papillae  and  nerves  of,  in  the  Frog  and  Toad,  139.  Tongue  of 
the  Frog,  139.  Vibratile  cilia  and  rugm,  141.  Conical  papillae,  142.  Nerves  of,  145.  Nerves 
of  the  inferior  surface  of  the  tongue,  146.  Mucous  follicles,  146.  Tongue  of  the  Toad,  147. 

Tortoise,  thoracic  segment  of,  compared  with  that  of  Birds,  157, — and  with  that  of  the  Crocodile, 
158. 

Transpiration  of  Gases,  349. 


U. 

Urine,  Contributions  to  the  Chemistry  of,  235.  I.  On  the  variations  in  the  acidity  of  the  urine 
in  a state  of  health,  235.  II.  On  the  simultaneous  variations  of  the  amount  of  uric  acid  and 
the  acidity  of  the  urine  in  a healthy  state,  245.  On  the  deposit  of  urates  in  the  urine,  251. 
III.  Variation  of  the  sulphates  in  the  urine  in  a healthy  state,  and  on  the  influence  of  sul- 
phuric acid,  sulphur  and  the  sulphates,  on  the  amount  of  sulphates  in  the  urine,  252.  On 
the  influence  of  caustic  potash,  tartaric  acid  and  the  tartrate  of  potash,  on  the  acidity  of  the 
urine,  265. 


V. 

Voltaic  Ignition,  eflPect  of  surrounding  media  on,  49. 

W. 

Waller  (Dr.  A.).  Minute  Structure  of  the  Papilla  of  the  Tongue  of  the  Frog  and  Toad,  139. 

Wax,  Investigation  on  the  Chemical  Nature  of.  III.,  91.  Myricin,  91.  Melissin,  93.  Melissic 
acid,  94.  Chlor-melal,  95.  Palmitic  acid  from  the  saponification  of  myricin,  96.  Distillation 
of  myricin,  98.  Palmitic  acid  from  the  distillation  of  myricin,  98.  Melen,  99. 

Williamson  (W.  C.,  Esq.).  On  the  Microscopic  Structure  of  the  Scales  and  Dermal  Teeth  of 
some  Ganoid  and  Placoid  Fish,  435. 


LONDON: 

PRINTED  BY  RICHARD  AND  JOHN  E.  TAYLOR, 
RED  LION  COURT,  FLEET  STREET. 


•TOu  t;o(  iohL^’I  '^AV'\jv'  -i-  \ . \ ■), V v -.'v  vV-  '.•i*.i, \v>'A  >Vm«v)  ._Y’ 

'.v'Yl-  /(o  ■/  ■ : .!  V,' 

! . '.i  f' -«>  ^';  ;/>•  .ihr^K  ■ 

' ^ ’!■ ' .Iv'i'i  ,v,;  I I',;'.  ■"■ 

"•‘r  •;i'r  ■.?!  oJi.f’i'ii/f 

^.  : . ■!•  ><1-'.  ’ .".'./"T'jK  iV’H  . n )’ '/J-Yf'T  k/fti;' ,;-.'n.-  ''  IT  ' ' ^• 

. ' . '.I';';.')  ;'■  .<!'  : v;H’ '(■.  ^ ' 

, -n,-  . : '''i*:')' l<i  i! !i''V  !■*.'  •' - jV.  V. i ^"-ti 't£.<  iOifiii'.  ^ .j-.i.ri'j  ,;i/  ■ : 'st-ai'''i'xtrV 


. ‘ ■ A:,'-:  ■ f ;£--.';.i:v •:;■«  k'.\ 

r '.K  «-'«*>,  .yi' 


.i'l  f ;iO  rtt'  I i! 

:^y'i  • 


■)  . ' . '!..  •^.j'v:''  ■■ 


';  , ' , ' ' ' ' '■  f ‘ ' ' i . , . ..• 

j/u;:  !';■^>^  :'■ 'S 

.,iV  ,-uyAli  t'ii  ifyi-'l;  Vy-'>f^o;y,h  '»:•;<!.  I'lY.li  '•<'  fti'ir''”' ;?»>!  . ; 

-!:>  . i't  '^0^■^:'^^I)'■^^  M'iU  !lu  '-'tb-i-.  .ib  '/th^  / .ill  '^,,' 

T'O  .'  rV.  /,m;:'/(;  U!  "iu' r.i  ..  ' , ,,  'luH -ij'lj  hr?A  ilurM”  'jjiuilcj  ■ V ■, 

vji.'; 'J')  ■■■^'•I)  fry  i%  --irti,'’#-?}),!  . ; birjft  yrr-ri;y)  .'hV/;.,  ^ 

s 


,i  'd‘’ 


:4iJ;;i(^S!.- -yiy  ", 


■■■  A '-A 


.0'' i .'p''<t‘!’  b.Ji.  ‘i  ■'..’s 'll*  t)  »;.)n'o' 1 ■sir ■ y:  ■ \K'\  .(.A  J'r 

•«•  :■'' I'.' a'-v'  .'jA't'.rr  j’l  . 1(1  ;<)f!)i’ivi4  JU  , J ! T '.M.ii  b<t  uyi:  . 

ii.u;;.!'  y ■;  ^ ■ ,'(’  • ' * -rf  t;;!?  bi ,b(l  r ,' 

.Cb*  (iJv'iYxfi:  ■ .V.;‘.>ih7«rl<>  >' ' '■'  ".;  . b '.'lii  -< ji'.ih.d  to  ' ■-<...  ‘-,t 

'i.v  ;■  ,>’('  i»;.,ii''Al  l)iirt  c^ilfcor'.  to ‘!;:uf'i4>fri:'.:'  yIat; r (>,,,  . i,r  ' 


rr’i'IrA 


'm 


‘ A "frcw’  ' ■■" 


' ;■  ;■ . ■ ■ '■  ''A-'- 

',,’•  ' V-.': 


r;T/):: 

' :;',fs 


,,  y ;!'  - 


\ 


■'  ^■; ' 

yM?;'  ,;  ■\,C..y.«  ’ "f.  '■'‘yA’i* 


■ V.,'  w (wW?")F  . -fi’/M ' " '■ 


V:, .V' ■ ■.  ,f Y 

.i!  f'-v.  TJ? 


.^■li.'i'At't  v:u'j  lt')i  bJ''' 

. ' ' ,.;A'V":  ..V  /’'  ..’  '^a."('y  : . "S'A>  ■ 


.'■'IV 


'%W'' 


PRESENTS 


RECEIVED  BY 


THE  ROYAL  SOCIETY, 

WITH  THE 

NAMES  OF  THE  DONORS. 


From  November  1848  to  June  1849. 

Presents. 

ACADEMIES  and  SOCIETIES. 

Berlin : — 

Abhandlungen  der  Kdniglichen  Akademie  der  Wissenschaften  zu  Berlin, 
aus  dem  Jahre  1846.  4to.  Berlin  1848. 

Monatsbericht.  January  1848  to  March  1849.  8vo. 

Die  Fortschritte  der  Physik  im  Jahre  1846,  dargestellt  von  der  Physika- 
lischen  Gesellschaft  zu  Berlin,  Zweiter  Jahrgang.  8vo.  Berlin  1848. 

Bombay  : — Transactions  of  the  Bombay  Geographical  Society  from  February 

to  December  1846,  April  to  September  1848..  8vo. 

Boston : — 

Memoirs  of  the  American  Academy  of  Arts  and  Sciences.  New  Series, 
Vol.  III.  4to.  Cambridge  and  Boston  1848. 

Proceedings  of  the  American  Academy  of  Arts  and  Sciences.  Vol.  I.  8vo. 
Boston  1848. 

Breslau : — 

Novorum  Actorum  Academiae  Caesareae  Leopoldino-Carolinae  Naturae 
Curiosorum.  Vol.  XXI.  Supplement.  Vol.  XXII.  4to.  Vratislavioe 
1846-47. 

Uebersicht  der  Arbeiten  und  Veriinderungen  der  Schlesischen  Gesellschaft 
fiir  vaterlandische  Kultur  im  Jahre  1847.  4to.  Breslau  1848. 

Brussels : — 

Memoires  de  I’Academie  Royale  de  Belgique.  Tome  XXI.  4tO:  Bruxelles 
1848. 

Memoires  Couronnes  de  I’Academie  Royale  de  Belgique.  Tome  XXII.  4to. 
Bruxelles  1848. 

Annales  de  I’Observatoire  Royal  de  Bruxelles.  Tome  VI.  4to.  Bruxelles 
1848. 

Bulletins  de  I’Academie  Royale  de  Belgique.  Tome  XIV.  Part  2.  Tome 
XV.  Part  1. 

Annuaire  de  I’Academie  Royale  de  Belgique.  8vo.  Bruxelles  1848. 


Donors. 


The  Academy. 


The  Society. 
The  Society. 


The  Academy. 


The  Academy. 


The  Society. 


The  Academy. 


WDCCCXLIX. 


a 


L 2 1 


Presents. 

ACADEMIES  and  SOCIETIES  {continued). 

Brussels : — 

Annuaire  de  I’Observatoire  Royal  de  Bruxelles  pour  1848.  8vo.  Bruxelles 
1847. 

Catalogue  des  livres  de  la  Bibliotheque  de  I’Observatoire  Royal  de  Brux- 
elles. 8vo.  Bruxelles  1847. 

Rapport  sur  I’Etat  et  les  Travaux  de  I’Observatoire  Royal  pendant  I’annee 

1847,  par  A.  Quetelet.  8vo.  Bruxelles  1847. 

Registres  de  la  Population  Belgique.  8vo.  Bruxelles  1848. 

Cornwall : — 

The  Tenth  Annual  Report  of  the  Royal  Cornwall  Polytechnic  Society, 
1842. 

The  Sixteenth  Annual  Report  of  the  Royal  Cornwall  Polytechnic  Society. 
8vo.  Falmouth  1848. 

Thirty-fifth  Annual  Report  of  the  Council  of  the  Royal  Geological  Society 
of  Cornwall.  8vo.  Penzance  1848. 

Dublin  : — 

The  Transactions  of  the  Royal  Irish  Acadenay.  Vol.  XXI.  Part  2.  4to. 
Dublin  1848. 

Proceedings  of  the  Royal  Irish  Academy.  Vol.  III.  Vol.  IV.  Part  1. 
Journal  of  the  Geological  Society  of  Dublin.  Vol.  III.  Part  4.  8vo. 
Edinburgh ; — 

Transactions  of  the  Royal  Society  of  Edinburgh.  Vol.  XVI.  Part  4,  and 
Vol.  XVIII. 

Proceedings  of  the  Royal  Society  of  Edinburgh.  Nos.  31,  32. 

Transactions  of  the  Royal  Scottish  Society  of  Arts.  Vol.  III.  Parts  2 and  3. 
8vo.  Edinburgh  1846-48. 

Glasgow: — Proceedings  of  the  Philosophical  Society  of  Glasgow.  Vol.  II. 
1841-48.  8vo.  Glasgow  1848. 

Gottingen  : — Nachrichten  von  der  Universitat  und  der  Kdnigl.  Gesellschaft 
der  Wissenschaften  zu  Gottingen  voin  Jahre  1848.  Nos.  1 to  14.  8vo.  Got- 
tingen 1848. 

Helsingfors : — 

Acta  Societatis  Scientiarum  Fennicee.  Tomus  II.  Pt.  4 et  Supp.  4to. 
Helsing for  sice  1847* 

Notiserur  Sallskapets  Pro  Fauna  et  Flora  Fennica  Forhandlingar ; Bihang 
till  Acta  Societatis  Scientiarum  Fennic®.  Fbrsta  haftet.  4to.  Helsingfors 

1848. 

Lausanne : — Bulletin  des  Seances  de  la  Societe  Vaudoise  des  Sciences  Na- 
turelles.  Nos.  16,  17,  18. 

Liverpool : — Proceedings  of  the  Literary  and  Philosophical  Society  of  Liver- 
pool. Nos.  1 to  4.  8 VO.  Liverpool  1846-48. 

London : — 

British  Archaeological  Association  Journal.  Nos.  6,  7 and  9 to  15  inclu- 
sive. 8vo. 

British  Association.  Report  of  the  British  Association  for  the  Advance- 
ment of  Science  for  1847.  8vo.  London  1848. 

Chemical  Society.  Quarterly  Journal.  Nos.  4 and  5.  8vo.  London  1849. 


Donors. 


The  Academy. 


The  Society. 

The  Society. 

The  Academy. 

The  Society. 

The  Society. 

The  Society. 

The  Society. 

Royal  Society  of  Sciences 
at  Gottingen. 

The  Society. 


The  Society. 

The  Society. 

The  Association. 
The  Association. 
The  Society. 


[ 3 ] 


Donors. 


Presents. 

ACADEMIES  and  SOCIETIES  (continued). 

London : — 

Geological  Society.  Quarterly  Journal.  Nos.  15,  16,  17,  18.  ISiS-iQ. 
Horticultural  Society.  Journal.  Vols.  1.  II.  and  Parts  1,  2.  Vol.  III.  8vo. 
London  1846-48. 

Medico-Chirurgical  Society.  Transactions.  Vol.  XXXI.  S\<j.  London  1848. 
Royal  Agricultural  Society.  Journal.  Vol.  IX.  Parts  1 & 2.  1848-49.  8vo. 
Royal  Asiatic  Society.  Journal.  No.  18.  8vo.  London  1848. 

Transactions  of  the  China  Branch  of  the  Royal  Asiatic  Society,  1847.  8vo. 
Hong  Kong  1848. 

Royal  Astronomical  Society.  Memoirs.  Part  1.  Vol.  XVII. 

Monthly  Notices,  November  1847  to  June 

1848.  8vo.  London  1848. 

Royal  Geographical  Society.  Journal.  Vol.  XVIII.  8vo.  1848. 

Statistical  Society.  Journal.  Parts  3 and  4,  Vol.  XI.  and  Vol.  XII.  1848. 
Zoological  Society.  Transactions.  Vol.  III.  Parts  5 and  6.  4to.  London 
1848. 

Proceedings.  Nos.  177  to  189.  8vo.  London  1847—48. 

Report:  General  Meeting,  April  29,  1848. 

Manchester: — Memoirs  of  the  Literary  and  Philosophical  Society  of  Man- 
chester. Vol.  VIII.  8vo.  London  1848. 

Moscow : — Bulletin  de  la  Societe  Imperiale  des  Naturalistes  de  Moscou,  for 
1847.  8vo.  Moscou  1847. 

Munich : — 

Abhandlungen  der  Philosophisch-Philologischen  Classe  der  Akademie  der 
Wissenschaften.  Abth.  2.  Vol.  IV.  4to.  Miinchen  1846. 

Abhandlungen  der  Historischen  Classe  der  Akademie  der  Wissenschaften. 

Abth.  1.  Vol.  IV.  4to.  Munchen  1844. 

Abhandlungen  der  Mathematisch-Physikalischen  Classe  der  K.  B.  Akademie 
der  Wissenschaften.  Fiinften  Bandes,  Zweite  Abtheilung.  4to.  Munchen 
1848. 

Abhandlungen  der  Philosophisch-Philologischen  Classe.  Vol.  V.  Abthei- 
lung 2.  4to.  Munchen  1849. 

Abhandlungen  der  Historischen  Classe.  Vol.  V.  Abtheilung  1.  4to. 
Munchen  1849. 

Bulletin  der  K.  Akademie  der  Wissenschaften,  1848.  Nos.  1 to  52.  4to. 
Munchen  1848. 

Denkschriften  der  Akademie  der  Wissenschaften.  Vols.  X.  to  XIV.  and 
Abtheilung  1.  Vol.  XV.  4to.  Munchen  1832-37. 

Denkrede  auf  J.  G.  Zuccarini  von  Dr.  Phil.  v.  Martins.  4to.  Munchen  1848. 
Gelehrte  Anzeigen.  Vol.  XV.  1842,  and  Vols.  XXVI.  and  XXVH.  4to. 
Munchen  1848. 

Observationes  Astronomicm  in  Specula  Regia  Monachiensi,  a J.  Lament. 
Vol,  XV.  4to.  Monachii  1847. 

Rede  bei  Eroffnung  der  Sitzung  der  Akademie  der  Wissenschaften  am  28 
Marz  1848,  von  Dr.  Phil.  v.  Martins.  4to.  Munchen  1848. 

Ueber  das  Ethische  Element  im  Rechtsprinzip,  von  A.  Buchner.  4to.  Mun- 
chen 1848. 

a 2 


The  Society. 
The  Society. 

The  Society. 
The  Society. 
The  Society. 
The  Society. 

The  Society. 


The  Society. 
The  Society. 
The  Society. 


The  Society. 


The  Society. 


The  Royal  Bavarian  Aca- 
demy of  Sciences,  Munich. 


[ 4 ] 


Presents. 

ACADEMIES  and  SOCIETIES  {coniinued'). 

Naples : — 

Atti  della  Reale  Accademia  delle  Scieuze  della  Societa  Reale  Borbonica. 

Vols.  1.  to  V.  4to.  Napoli  1819-44. 

Rendiconto.  Vols.  III.  to  VI.,  and  Nos.  37,  38.  4to.  Napoli  1844-48. 

New  York : — Annals  of  the  Lyceum  of  Natural  History  of  New  York.  8vo. 
New  York  1847. 

Oxford  : — Proceedings  of  the  Ashmolean  Society.  No.  25.  8vo. 

Paris : — 

Academie  des  Sciences.  Comptes  Rendus.  Tome  XXVI.,  XXVII.  4to. 
Paris  1848. 

Annales  de  la  Societe  Entomologique  de  France.  Tome  VI.  Nos.  1,  2. 
8vo.  Paris  1848. 

Archives  du  Museum  d’Histoire  Naturelle.  Tome  IV.  Liv.  3.  4to.  Paris 
1849. 

Bulletin  de  la  Societe  de  Geographie.  Tom.  VIII.  IX.  8vo.  Paris  1847-48. 
Bulletin  de  la  Societe  Geologique  de  France.  Tom.  IV.  Nos.  53  to  78. 
Tom.  V.  Nos.  1 to  32.  Tom.  VI.  Nos.  1 to  18.  8vo.  Paris  1846-49. 
Philadelphia : — 

Transactions  of  the  American  Philosophical  Society.  Vol.  X.  Part  1.  4to. 
Philadelphia  1 847. 

Proceedings  of  the  American  Philosophical  Society.  Nos.  36  to  41.  1846-48. 
Journal  of  the  Academy  of  Natui’al  Sciences  of  Philadelphia.  Vol.  I. 

Parts  1,  2.  4to.  Philadelphia  1847-48. 

Proceedings  of  the  Academy  of  Natural  Sciences  of  Philadelphia.  Nos.  11, 
12,  Vol.  III.  No.  1,  Vol.  IV.  8vo.  Philadelphia  1846-48. 

Journal  of  the  Franklin  Institute.  Vols.  IX.  X.  XIII.  XIV.  8vo.  Phila- 
delphia 1845-47. 

Prague ; — Abhandlungen  der  Kbniglichen  Bdhmischen  Gesellschaft  der 
Wissenschaften.  4to.  Prag  1848. 

St.  Petersburg : — 

Memoires  de  I’Academie  Imperiale  des  Sciences  de  St.  Petersbourg.  Sci- 
ences Mathematiques.  Tome  IV.  Liv.  5 and  6.  Tome  V.  Liv.  1 and  2. 
Tome  VI.  Liv.  1 and  2.  4to.  St.  Petersbourg  1848. 

Memoires  de  I’Academie  Imperiale  des  Sciences  de  St.  Petersbourg. 
Sciences  Politiques.  Tome  VII.  Liv.  4,  5,  6-  4to.  St.  Petersbourg 
1847-48. 

Bulletin  de  la  Classe  Historico-Philologique.  Tome  III.  Nos.  67  to  72. 

Tome  IV.  4to.  St.  Petersbourg  1847-48. 

Bulletin  de  la  Classe  Physico-Mathematique.  Tome  V.  Nos.  117  to  120. 

Tome  VI.  4to.  St.  Petersbourg  1847-48. 

Recueil  des  Actes  de  la  Seance  Publique  de  I’Academie  Imperiale  des 
Sciences  de  St.  Petersbourg  tenue  le  29  Decembre  1845  et  Janvier 

1847.  4to.  St.  Petersbourg  1848. 

Stockholm : — 

(ifversigt  af  Kongl.  Vetenskaps-Akademiens  Forhandlingar.  Nos.  7 to  9, 
Fjerde  Argiingen  1847,  and  1 to  6,  S'*®  Argangen  1848.  8vo.  Stockholm 

1848. 


Donors. 

The  Academy. 

The  Lyceum. 

The  Society. 

The  Institute  of  France. 

The  Society. 

The  Museum. 

The  Society. 

The  Society. 

The  Society. 

The  Society. 

The  Academy. 

The  Institute. 

The  Society. 

The  Imperial  Academy. 


Royal  Academy  of  Sciences 
at  Stockholm. 


r s ] 


Donors. 


Presents. 

ACADEMIES  and  SOCIETIES  {continued). 

Stockholm : — 

Kongl.  Vetenskaps- Akadeinieris  Plandlingar  for  ar  184'6. 

Arsberiittelse  om  Zoologiens  Framsteg  under  aren  1845  och  1846,  af  C.  H. 
Boheman.  8vo.  Stockholm  1847. 

Arsberattelse  om  Framstegen  i Kemi  och  Mineralogi  afgiven  den  31  Mars 
1847.  8 VO.  Stockholm  1848. 

Arsberattelse  om  Zoologiens  Framsteg  under  aren  1843-44.  Tredje  Delen, 
af  S.  Loven.  8vo.  Stockholm  1848. 

Turin : — Memorie  della  Reale  Accademia  delle  Scienze  di  Torino.  Tomo 
IV.  VI.  VII.  VIII.  and  IX.  4to.  Torino  1842-48. 

Utrecht : — 

Aanteekeningen  van  het  verhandelde  in  de  Sectie-Vergaderingen  van  het 
Provinciaal  Utrechtsch  Genootschap  van  Kunsten  en  Wetenschappen, 
ter  Gelegenheid  van  de  Algemeene  Vergadering  in  1847-48.  8vo. 
Utrecht  1847-48. 

Verslag  van  het  Verhandelde  in  de  Algemeene  Vergadering  van  het  Pro- 
vinciaal Utrechtsch  Genootschap  van  Kunsten  en  Wetenschappen  voor 
1847-48. 

Venice: — Esercitazioni  Scientifiche  e Letterarie  dell’ Ateneo  Veneto.  Part  1. 

Vol.  VI. 

Zurich : — 

Mittheilungen  der  Naturforschenden  Gesellschaft  in  Zurich.  Heft  1 and  2. 
Nos.  1 to  26.  8vo.  Zurich  1847-48. 

Denkschrift  zur  Feier  des  Hundertjahrigen  Stiftungfestes  der  Naturfor- 
schenden Gesellschaft  in  Zurich  am  30  Nov.  1846.  4to.  Zurich  1846. 
Meteorologische  Beobachtungen  angestellt  auf  Veranstaltung  der  Natur- 
forschenden Gesellschaft  in  Zurich,  1837-48.  4to.  Zurich. 

ACLAND  (H.  W.)  Remarks  on  the  Extension  of  Education  at  the  Uni- 
versitj"^  of  Oxford,  in  a letter  to  the  Rev.  W.  Jacobson,  D.D.  8vo.  Oxford 
1848. 

ADAMS  (Arthur)  (Editor.)  The  Zoology  of  the  Voyage  of  H.M.S.  Samarang. 
Nos.  1,  2,  3.  4to.  London  1848. 

AIRY  (G.  B.)  Astronomical  Observations  made  at  the  Royal  Observatory, 
Greenwich,  in  1846.  4to.  London  1848. 

Magnetical  and  Meteorological  Observations  made  at  the  Royal 

Observatory,  Greenwich,  in  1846.  4to.  London  1848. 

Reduction  of  the  Observations  of  the  Moon,  made  at  the  Royal 

Observatory,  Greenwich,  from  1750  to  1830.  2 vols.  4to.  London  1848. 
ALLEN  (Capt.  W.)  Narrative  of  the  Expedition  to  the  Niger  in  1841.  By 
Captain  Allen,  R.N.,  F.R.S.,  and  Dr.  Thomson.  2 vols.  8vo.  London  1848. 
ANONYMOUS:— 

A Narrative  of  Recent  Occurrences  in  Posen.  8vo.  London  1848. 

Annales  des  Mines.  Vols.  1.  to  XL  and  Livraison  1,  5,  6,  Vol.  XII.  and  1,  2, 
Vol.  XIII.  8vo.  Paris  1842-48. 

Annuaire  du  Bureau  des  Longitudes  pour  I’an  1848.  8vo.  Paris  1847. 
Annuaire  Meteorologique  de  la  France  pour  1849.  8vo.  Paris  1848. 


Royal  Academy  of  Sciences 
at  Stockholm. 


The  Academy. 

The  Society. 


The  Institution. 

The  Society. 


The  Autlior. 

Lovell  Reeve,  Esq. 

The  Lords  of  the  Admiralty. 


Captain  Allen,  F.R.S. 

Lord  Dudley  Stuart. 
L’Ecole  des  Mines. 

Le  Bureau  des  Longitudes. 
The  Authors. 


[ 6 ] 


Presents. 

ANONYMOUS  {continued). 

Buildings  and  Monuments,  Modern  and  Mediaeval,  edited  by  George  God- 
win, F.R.S. 

Catalogue  of  the  Fellows  and  Licentiates  of  the  Royal  College  of  Physicians. 

1848. 

Connaissance  des  Temps  pour  I’an  1851.  8vo.  Paris  1848. 

Dictionary  of  Greek  and  Roman  Biography  and  Mythology.  Edited  by  W. 
Smith,  LL.D.  Parts  25,  26,  27. 

Engravings  from  Ancient  Seals  attached  to  Deeds  and  Charters  in  the  Muni- 
ment Room  of  Sir  Thomas  Hare,  Bart.  fol.  Stowe- Bardolpli  1847. 

Eighth  and  Ninth  Annual  Reports  of  the  Registrar-General.  8vo.  London 

1849. 

F'lora  Batava.  Nos,  144,  145,  146  and  152  to  155.  4to. 

List  of  the  Fellows  and  Members  of  the  Royal  College  of  Surgeons  of 
England.  8vo.  London  1848. 

Memoirs  of  the  Geological  Survey  of  the  United  Kingdom.  Decade  1.  4to. 
L^ondon  1849. 

Monurnenta  Historica  Britannica;  or  Materials  for  a History  of  Britain, 
published  by  command  of  Her  Majesty.  Vol.  I.  fol.  London  1848. 

Papers  relating  to  the  Arctic  Expedition  laid  before  Parliament. 

Quarterly  Report  of  the  Registrar-General,  December  1848. 

Report  of  the  Council  of  the  Art-Union  of  London  for  the  year  1848.  8vo. 
I^ondon  1848. 

Report  of  the  Sixteenth  Annual  Meeting  of  the  Literary  Association  of  the 
FTiends  of  Poland.  8vo.  London  1848. 

Report  on  Quarantine.  Presented  to  Parliament.  8vo.  London  1849. 

Reports  of  the  Metropolitan  Sanitary  Commissioners,  fol.  London  1847, 
Reports  of  the  Registrar-General,  June  and  September  1848. 

Reports  of  the  Royal  College  of  Chemistry.  Vol.  I.  8vo.  London  1849. 
Summary  of  the  London  Returns  of  Mortality  for  eleven  years,  18S8— 48. 
Supplement  to  the  Bai'bados  Agricultural  Reporter.  No.  8.  Vol.  IV. 

The  Anglo-Saxon.  Part  1.  8vo.  London  1849. 

The  Art-Union  of  London  and  the  Board  of  Trade. 

The  London  University  Calendar,  1849. 

The  Moral  Play  of  Wit  and  Science,  edited  by  J.  O.  Halliwell,  Esq.,  F.R.S. 
8 VO.  London  1848. 

ANSTED  (D.  T.)  The  Gold-Seeker’s  Manual.  8vo.  London  1849. 

ARAGO  (J.  F.  D.)  Biographie  de  M.  de  Condorcet.  4to.  Paris  1849. 

ART  (Works  of,  &c.). 

Bronze  Copy  of  a Medal  struck  by  the  Royal  Society  of  Edinburgh,  bearing 
the  Effigy  of  Napier  of  Merchiston,  the  Inventor  of  Logarithms. 

Bust  in  Plaster  of  Don  Jorge  Juan,  Director  of  the  Observatory  of  San  Fer- 
nando. 

View  of  Ancient  London  and  Westminster  in  1548. 

View  of  James  Town,  St.  Helena,  during  the  Rollers  of  the  l7th  of  February 
1846,  by  Lieut.  Stack. 


Donors. 

The  Editor. 

The  College. 

Le  Bureau  des  Longitudes. 
The  Editor. 

Rev.  G.  H.  Dashwood. 

The  Registrar-General. 


H.  M.  the  King  of  the 
Netherlands. 

The  College. 

The  Directors  of  the  Geo- 
logical Survey. 

The  Secretary  of  State  for 
the  Home  Department. 
The  Admiralty. 

The  Registrar-General. 

The  Art-Union. 

Lord  Dudley  Stuart. 

The  General  Board  of 
Health. 

The  Commissioners. 

The  Registrar-General. 

The  College. 

The  Registrar-General. 

Dr.  Davy,  F.R.S. 

The  Editor. 

The  Art-Union. 

The  University. 

The  Editor. 

The  Author. 

The  Author. 

The  Royal  Society  of  Edin- 
burgh. 

Senor  J.  S.  Cerquero. 

The  Publishers. 

The  Author. 


I 7 J 


Presents. 

ATKINS  (Mrs.)  Photographs  of  British  Algae.  Parts  9 and  10. 

BAILIE  (J.  K.)  Fasciculus  Inscriptionuiii,  Graecarum  potissiinum  ex  Galatia, 
Lycia,  Syria  et  iEgypto,  edidit.  4to.  Dublinii  1849. 

BEINERT  (C.  C.)  Der  Meteorit  von  Braunau  am  14  Juli  1847.  8vo.  Breslau 

1848. 

BEKE  (C.  T.)  Memoire  justificatif  en  Rehabilitation  des  Peres  Pierre  Paez 
et  Jerome  Lobo  en  ce  qui  concerne  leurs  visites  a la  Source  de  I’Abai  (le 
Nil).  8vo.  Paris  1848. 

An  Essay  on  the  Sources  of  the  Nile  in  the  Mountains  of  the 

Moon.  8vo.  Edinburgh  1848. 

BESSEL  (F.  W.)  Populare  Vorlesungen  liber  Wissenschaftliche  Gegenstande. 
8vo.  Hamburg  1848. 

BISHOP  (G.)  Remarks  and  Notes  to  Mr.  Bishop’s  Ecliptic  Chart. 

Chart  accompanying  the  above.  Hour  1. 

BLANCHARD  (Emile.)  Du  Systeme  Nerveux  chez  les  Invertebres  (Mol- 
lusques  et  Anneles),  &c.  8vo.  Paris  1849. 

BOGUE  (Adam.)  Steam  to  Australia,  its  general  advantages  considered.  8vo. 
Sydney  1848. 

BOTFIELD  (B.)  Bibliotheca  Hearneiana.  Excerpts  from  the  Catalogue  of 
the  Library  of  Thomas  Hearne,  xA..M.  8vo.  London  1848- 

Catalogue  of  Pictures  in  the  possession  of  Beriah  Botfield,  Esq. 

8vo.  London  1848. 

Notes  on  the  Cathedral  Libraries  of  England.  8vo.  London 

1849. 

BOUCHER  (C.  F.)  Recherches  sur  la  Structure  des  Organes  de  fHomme  et 
des  Animaux  les  plus  connus.  8vo.  Paris  1848. 

BOWMAN  (W.)  Lectures  on  the  parts  concerned  in  the  Operations  on  the 
Globe,  and  on  the  Structure  of  the  Retina.  8vo.  London  1848. 

BOYD  (B.)  A Letter  to  Sir  W.  Denison,  Lieut.  Gov.  of  Van  Diemen's  Land, 
on  the  Expediency  of  transferring  the  unemployed  labour  of  that  Colony 
to  New  South  Wales.  8vo.  Sydney  1847. 

Competence  in  a Colony  contrasted  with  Poverty  at  Home.  8vo. 

London  1848. 

BRITTON  (J.)  The  Authorship  of  the  Letters  of  Junius  elucidated.  4to. 
London  1848. 

BUSCH  (A.  L.)  Astronomische  Beobachtungen  auf  der  Kdnigl.  Universitiits- 
Sternwarte  in  Kdnigsberg.  Abth.  23.  fol.  Kdnigsberg  1847. 
CARPENTER  (W.  B.)  On  the  Development  and  Metamorphoses  of  Zoo- 
phytes. 

Report  on  the  Microscopic  Structure  of  Shells.  8vo. 

London  1848. 

CAUCHY  (A.  L.)  Exercices  d’Analyse  et  de  Physique  Mathematique.  Nos. 
38,  39,  40. 

Methode  pour  determiner  a priori  le  nombre  des  Racines 

reelles  positives  et  le  nombre  des  Racines  reelles  negatives  d’uue  equation 
d’un  degre  quelconque.  8vo.  Paris  1813. 

Rapports  sur  divers  Memoires  lus  a la  Premiere  Classe  de 

rinstitut  Imperial.  8vo.  Paris  1813. 


Donors. 
The  Author. 
The  Author. 

The  Author. 

The  Author. 


The  Author. 

The  x\uthor. 

The  Author. 

L.  Boyd,  Esq. 

B.  Botfield,  Esq.,  F.R.S. 


The  Author. 
'I'he  Author. 
L.  Boyd,  Esq 


The  x\utlior. 

The  Observatory. 
The  Author. 


The  .Author. 


[ 8 1 


Presents. 

CAUCHY  (A.  L.)  Sur  la  Theorie  de  la  Lumiere. 

CAUTLEY  (P.  T.)  and  FALCONER  (H.)  Fauna  Antiqua  Sivalensis.  Parts 
7,  8,  9.  fol.  London  1847-4'9. 

CERQUERO  (J.  S.)  Almanaque  Nautico  y Efemerides  Astronomicas  para 
los  Anos  de  184'5-1850,  calculadas  de  orden  de  S.  M.  Para  el  Observatorio 
de  Marina  de  la  Ciudad  de  S.  Fernando.  4to.  Madrid  1843-48. 

Periodico  Mensual  de  Cieneias  Matematicas  y Fisicas. 

Tomo  I.  No.  1 to  6.  4to.  Cadiz  1848. 

CHALLIS  (Rev.  James.)  Astronomical  Observations  made  at  the  Cambridge 
Observatory  for  1843.  Vol.  XV.  4to.  Cambridge  1848. 

CIVIALE  (Dr.)  De  I’Uretrotomie,  ou  de  quelques  Precedes  peu  usites  de 
trailer  les  Retrecissements  de  I’Uretre.  8vo.  Paris  1849. 

COLQUHOUN  (E.  P.)  An  Authentic  Interpretation  of  the  Guarantee  of 
England  and  France  with  reference  to  the  Duchy  of  Schleswig,  by  Dr.  Le- 
verkus,  translated  and  edited  with  prefatory  remarks.  8vo.  London  1848. 

CRAWFURD  (John.)  Vital  Statistics  of  a District  in  Java. 

DANA  (James  D.)  Review  of  Chambers’s  Ancient  Sea  Margins.  8vo.  New- 
Jiaven  1848. 

D’ARCHIAC  (A.)  Histoire  des  Progres  de  la  Geologic.  Tome  deuxieme. 
Premiere  Partie.  8vo.  Paris  1848. 

DAUSSY  (P.)  Table  des  Positions  G eographiques  des  Principaux  Lieux  du 
Globe.  8vo. 

DAVY  (John.)  Lectures  on  the  Study  of  Chemistry  in  connexion  with  the 
Atmosphere,  the  Earth,  and  the  Ocean.  8vo.  London  1849. 

DE  BEAUMONT  (Elie.)  Explication  de  la  Carte  Geologique  de  la  France, 
redigee,  &c.  Tome  II.  4to.  Paris  1848. 

DE  KONINCK  (L.)  Recherches  sur  les  Animaux  Fossiles.  4to.  Liege  1847. 

DE  LA  BECHE  (Sir  H.  T.)  Address  delivered  at  the  Anniversary  Meet- 
ing of  the  Geological  Society  of  London,  on  the  16th  of  February  1849. 
8vo.  London  1849. 

DE  LA  RIVE  (A.)  Researches  on  the  Voltaic  Arc,  from  the  Philosophical 
Transactions.  4to.  London  1847. 

DE  MORGAN  (A.)  On  the  Additions  made  to  the  second  edition  of  the 
Commercium  Epistolicum. 

Trigonometry  and  Double  Algebra.  8vo.  London  1849. 

DE  NOBREGA  (G.  J.)  On  tlie  Cultivation  of  Cochineal.  London 

DENT  (E.  J.)  A Treatise  on  the  Aneroid  Barometer.  8vo.  London  1849. 

DE  PERTHES  (Boucher).  Antiquites  Celtiques  et  Antediluviennes.  8vo. 
Paris  1847. 

DE  RIVAZ  (C.)  Description  des  Eaux  Minero-Thermales  et  des  Etuves,  de 
rile  dTschia.  8vo.  Naples  1846. 

Voyage  de  Naples  a Capri  et  a Paestum.  8vo.  Naples  1846. 

DILLWYN  (L.  W.)  Materials  for  a Fauna  and  Flora  of  Swansea  and  the 
Neighbourhood.  8vo.  Swansea  1848. 

DORAL  (Antonio).  Memoria  Descriptiva  del  Circulo  de  Marcar  y sus  Apli- 
caciones.  8vo.  Madrid  1848. 

DRACH  (S.  M.)  An  easy  Rule  for  Formulizing  all  Epicyclical  Curves  with 
one  moving  circle  by  the  Binomial  Theorem. 


Donors. 

The  Author. 

The  Marquis  of  Northamp- 
ton, V.P.R.S. 

The  Observatory  of  San 
Fernando. 


The  Observatory. 
The  Author. 

The  Editor. 


Lieut.-Col.  Sykes. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  French  Government. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 


The  Author. 

The  Author. 

The  Author,  by  Mr.  Roach 
Smith. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 


[ 9 ] 


Presents. 

DUFRENOY  and  DE  BEAUMONT  (E.)  Explication  de  la  Carte  Geolo- 
gique  redigee,  &c.  Tom.  II.  4to.  Paris  1848. 

DUMONT  (A.)  Memoire  sur  les  Terrains  Ardennais  et  Rhenan.  4to.  Brux- 
elles 1848. 

DU  POTET  (Le  Baron.)  Journal  du  Magnetisme.  Tom.  I.  to  V.  8vo.  Paris 
1845-47. 

DURAN  (J.  A.)  Code  des  Creations  Universelles  et  de  la  Vie  des  £itres. 
8 VO.  Bordeaux  1841. 

Nouveau  Systeme  de  Physique  generale  en  opposition  avec 

les  Principes  re^us.  8vo.  Paris  1843. 

ELLIOTSON  (J.)  Cure  of  a true  Cancer  of  the  Female  Breast  with  Mes- 
merism. 8 VO.  London  1848. 

ENCKE  (J.  F.)  Astronomische  Beobachtungen  auf  der  Kdniglichen  Stern- 
warte  zu  Berlin.  Dritter  Band.  4to.  Berlin  1848. 

Berliner  Astronomisches  Jahrbuch  fiir  1851.  8vo.  Berlin 

1848. 

ERMAN  (A.)  Reise  um  die  Erde  durch  Nord-Asien  und  die  beiden  Oceane 
in  den  Jahren  1828,  1829  und  1830.  3rd  Band  and  Atlas.  8vo.  Berlin 

1848. 

FALCONER  (H.)  and  CAUTLEY  (P.  T.)  Fauna  Antiqua  Sivalensis.  Parts 
7,  8,  9.  fol.  London  1 847-49. 

FORBES  (John.)  A Physician’s  Holiday.  8vo.  London  1849. 

FORSTER  (T.  J.  M.)  L’Age  d’Or,  ou  Pensees  Passageres  adressees  comme 
Discours  prHiminaire  a ceux  qui  suivent  la  science  dans  sa  marche  d’au- 
jourd’hui  vers  la  perfection  de  I’avenir.  8vo.  Bruges  1847. 

Memoire  sur  les  Etoiles  Filantes.  8vo.  Bruges  1846. 

FRODSHAM  (C.)  A few  Remarks  upon  the  construction  and  principles  of 
action  of  the  Aneroid  Barometer.  8vo.  London  1849. 

FROST  (James.)  Description  of  the  Causes  of  the  Explosion  of  Steam-Boilers. 
8vo.  New  York  1848. 

GIBBES  (R.  W.,  M.D.)  Monograph  of  the  Fossil  Squalidae  of  the  United 
States.  4to.  Philadelphia  1848. 

GILBART  (J.  W.)  A Record  of  the  proceedings  of  the  London  and  West- 
minster Bank.  4to.  London  1847. 

A Review  of  the  Practical  Working  of  the  Act  of  1844 

for  regulating  the  issue  of  Notes  by  the  Bank  of  England.  8vo.  London 

1849. 

GLAISHER  (J.)  Remarks  on  the  Weather  during  the  quarters  ending 
March  31,  June  30  and  September  30,  1848. 

GOULD  (J.)  An  Introduction  to  the  Birds  of  Australia.  8vo.  London  1848. 

The  Birds  of  Australia.  Parts  31  to  36. 

GRANTHAM  (R.  B.)  A Treatise  on  Public  Slaughter  Houses.  8vo.  London 
1848. 

GRAY  (J.  E.)  A Letter  to  the  Earl  of  Ellesmere  on  the  Management  of  the 
Library  of  Printed  Books  in  the  British  Museum.  8vo.  London  1849. 

GRIFFITH  (W.)  Journals  of  Travels  in  India.  8vo.  Calcutta  1847. 


Donors. 

The  French  Government. 
The  Author. 

Le  Baron  Du  Potet. 

The  Author. 


The  Author. 

The  Observatory. 


The  Author. 

The  Marquis  of  Northamp- 
ton, V.P.R.S. 

The  Author. 

The  Author. 


The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Marquis  of  Northamp- 
ton, V.P.R.S. 

The  Author. 

The  Author. 

The  Directors  of  the  East 
India  Company. 


MDCCCXLIX. 


h 


[ 10  ] 


Presents. 

GRIFFITH  (W.)  Development  of  Organs  in  Phanerogamous  Plants.  8vo. 
Calcutta 

Atlas  to  the  above,  ■ito.  Calcutta  1847. 

HALL  (Marshall.)  Essays  chiefly  on  the  Theory  of  Paroxysmal  Diseases  of  the 
Nervous  System. 

A Letter  addressed  to  the  Earl  of  Rosse,  President-Elect 

of  the  Royal  Society.  2nd  edit.  8vo.  London  1848. 

HERSCHEL  (Sir  J.  F.  W.,  Bart.)  Outlines  of  Astronomy.  8vo.  London  1849. 
HOMERSHAM  (S.  C.)  Supplement  to  the  Report  to  the  Directors  of  the 
Manchester,  Sheffield  and  Lincolnshire  Railway  Company,  on  the  Supply 
of  Surplus  Water  to  Manchester,  Salford  and  Stockport.  8vo.  London 

1848. 

HOWARD  (Luke.)  Barometrographia.  fol.  Zo/irfora  1 847. 

JERWOOD  (J.)  A Lecture  on  the  New  Planet  Neptune,  and  its  Discovery. 
8 VO.  London  1849. 

JOBERT  (A.  J.)  Traite  de  Chirurgie  Plastique.  2 vols.  and  Atlas.  S\o.  Paris 

1849. 

JOHNSON  (M.  J.)  Astronomical  Observations  made  at  the  Radcliffe  Ob- 
servatory, Oxford,  in  1846.  Vol.  VII.  8vo.  Oxford  1848. 

JOURNALS 

Astronomische  Nachrichten.  Nos.  628  to  665. 

Calcutta  .Journal  of  Natural  History.  No.  30.  8vo.  Calcutta  1847- 

Journal  of  the  Agricultural  and  Horticultural  Society  of  India.  Vol.  VI. 
Parts  2,  3.  8vo.  Calcutta  1847. 

Journal  of  the  Asiatic  Society  of  Bengal.  February  to  June  1848,  and  Nos. 
192  to  199.  8 VO.  Calcutta  1848-49. 

Journal  of  the  Indian  Archipelago.  Supplement  to  No.  6.  Vol.  I.  Nos.  3 to 
12.  Vol.  H.  Nos.  1,  2.  Vol.  III.  8vo.  Singapore  1848-49. 

Scheikundige  Onderzoekingen  Gedaan  in  het  Laboratorium  der  Utrechtsche 
Hoogeschool.  5*^®  Deel,  3 & 4 Stuken.  8vo.  Rotterdam  1849. 

The  American  Journal  of  Science  and  Arts.  Vols.  XL.  to  XLIX.  1841-45. 

Index  Volume  to  First  Series. 

Vols.  I.  to  VII.  Second  Series.  1846-49. 

The  Athenaeum.  January  to  June  1849. 

The  Boston  Journal  of  Natural  History.  Vols.  1.  11.  8vo.  Boston  1834-39. 
The  Builder.  Parts  1 to  5.  Vol.  VII.  1849. 

The  Literary  Gazette.  January  to  June  1849. 

JUPP  (E.  B.)  An  Historical  Account  of  the  Worshipful  Company  of  Car- 
penters. 8vo.  London  1848. 

KARSTEN  (H.)  Die  Vegetationsorgane  der  Palmen.  4to.  Berlin  1847. 
KING  (Capt.  P.  P.)  On  the  Specific  Gravity  of  Sea-Water. 

Selections  from  a Meteorological  Journal  kept  on  board 

H.M.S.  Adventure. 

KREIL  (K.)  Magnetische  und  Geographische  Ortsbestimmungen  im  Oster- 
reichischen  Kaiserstaate.  4to.  Brag  1848. 

Magnetische  und  Meteorologische  Beobachtungen  zu  Prag.  4to. 

Prag  1848. 


Donors. 

The  Directors  of  the  East 
India  Company. 

The  Author. 


The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Radcliffe  Trustees. 


Professor  Schumacher. 

The  Directors  of  the  Hon. 

East  India  Company. 

The  Society. 

The  Society. 

The  Editor. 

The  Utrecht  Society  of 
Sciences. 

Messrs.  Silliman. 


The  Editor. 

The  Editor. 

The  Editor. 

The  Editor. 

The  Carpenters’  Company. 

The  Author. 

The  Author. 


The  Author. 


[ 11  ] 


Presents. 

KUPFFER  (A.)  Annuaire  Magnetique  et  Meteorologique  de  Russie,  annee 
1845.  4to.  St.  Petershourg  1848. 

Resumes  des  Observations  Meteorologiques,  &c.  4to.  St.  Pe- 

tersbourg  1848. 

LAMONT  (J.)  Annalen  der  Kdniglichen  Sternwarte  bey  Miinchen.  8vo. 
Munchen  1848. 

LAPLACE  (P.  S.  de.)  Qiuvres: — Traite  de  Mecanique  Celeste,  5 vols. 
Exposition  du  Systeme  du  Monde,  1 vol.  Theorie  Analytique  des  Proba- 
bilites,  1 vol.  4to.  Paris  1843-47- 

LEE  (Robert.)  Memoirs  on  the  Ganglia  and  Nerves  of  the  Uterus.  4to.  Lon- 
don 1849. 

LEIDY  (Joseph.)  On  a new  Fossil  Genus  and  Species  of  Ruminantoid  Pachy- 
dermata,  Merycoidodon  Culbertsonii. 

On  a new  genus  and  species  of  Fossil  Ruminantia. 

On  some  bodies  in  the  Boa  Constrictor  resembling  the  Paci- 
nian Corpuscles. 

Researches  into  the  Comparative  Structure  of  the  Liver. 

LIBRI  (M.)  Reponse  de  M.  Libri  au  Rapport  de  M.  Boucly.  8vo.  London 
1848. 

LLOYD  (Rev.  H.)  An  Account  of  a Method  of  determining  the  Total  Inten- 
sity of  the  Earth’s  Magnetic  Force  in  Absolute  Measure. 

Circular  for  the  Information  of  the  Directors  of  the  Bri- 
tish Colonial  Magnetical  Observatories.  8vo. 

On  the  Corrections  required  in  the  Measurement  of  the 

Magnetic  Declination. 

On  the  Mean  Results  of  Observations.  4to.  Dublin  1849. 

Results  of  Observations  made  at  the  Magnetical  Observa- 
tory of  Dublin  during  the  years  1840-43.  4to.  Dublin  1849. 

LOUYET  (M.)  De  I’Ebullition  des  Liquides.  8vo.  Bruxelles. 

LOVELACE  (Earl  of.)  On  Climate  in  connection  with  Husbandry.  8vo. 
London  1848. 

On  Harbours  of  Refuge.  8vo.  London  1849. 

Review  of  the  work  of  Messrs.  Rubichon  and  Mou- 

nier,  and  of  the  Memoir  of  M.  Benoiton  de  Chateauneuf.  8vo.  London 
1848. 

Review  of  “Du  Systeme  Social”  by  A.  Quetelet. 

LOWE  (Edward.)  Prognostications  of  the  Weather,  or  Signs  of  Atmospheric 
Changes.  8vo.  London  1849. 

LUBBOCK  (J.  W.)  Appendix  to  a Treatise  “ On  the  Theory  of  the  Moon.” 

On  the  Theory  of  the  Moon,  &c.  Parts  6,  7.  8vo.  Lon- 
don 1848-49. 

MACKINNON  (W.  A..)  History  of  Civilization.  2 vols.  8vo.  London  1846. 

MADLER  (J.  H.)  Beobachtungen  der  Kaiserlichen  Universitats  Sternwarte, 
Dorpat.  Elfter  Band.  4to.  Dorpat  1845. 

MANTELL  (G.  A.)  A brief  Notice  of  the  Organic  Remains  recently  disco- 
vered in  the  Wealden  Formation.  8vo.  London  1849. 

— On  the  Fossil  Remains  of  Birds  collected  in  New  Zea- 
land by  Walter  Mantell,  Esq.  8vo.  London  1848. 

h 2 


Donors. 

The  Russian  Government. 


The  Observatory. 

The  French  Government. 

The  Author. 

The  Author. 


The  Author. 
The  Author. 
Col.  Sabine. 
The  Author. 


The  Author. 
The  Author. 


The  Author. 
The  Author. 


The  Author - 
The  Author. 

The  Author. 


[ 12  ] 


Presents. 

MAPS,  CHARTS,  &c.:— 

Admiralty  Charts  and  Sailing  Directions  published  during  1848. 

Eight  Cartes,  published  by  the  Depot  de  la  Marine,  1848. 

L’Afrique  d’apres  une  Carte  de  la  fin  du  IT^me  Siecle,  de  la  Bibliotheque  de 
M.  Beat  de  Berber,  1841. 

MARTIN  (George  A.)  The  Undercliff  of  the  Isle  of  Wight;  its  Climate, 
History  and  Natural  Productions.  8vo.  London  1849. 

MARTIN  (John.)  Documents  and  Drawings  relating  to  the  Thames  and  Me- 
tropolis Improvement.  London  1836-49. 

MARTINS  (C.)  Essai  sur  la  Vegetation  de  I’Archipel  des  Feroe.  8vo. 

MAYO  (Thomas.)  Sequel  to  Outlines  of  Medical  Proof.  8vo.  London  1849- 
MISCELLANEOUS 

A Lock  of  the  Hair  of  the  late  Sir  Flumphry  Davy,  Bart. 

Specimens  of  Tea  produced  in  the  District  of  Kumaon  in  the  N.W.  Provinces 
of  the  Bengal  Presidency. 

Two  Specimens  of  Meteoric  Iron. 

MOON  (Robert.)  Fresnel  and  his  Followers:  a Criticism.  8vo.  Cambridge 
1849. 

MORTILLARO  (Vincenzo.)  Illustrazione  di  un  Astrolabio  Arabo-Siculo. 
8vo.  Palermo  1848. 

MOUAT  (F.  J.)  The  Elements  of  Anatomy,  translated  into  Hindustani. 
8vo.  Calcutta  1848. 

NAPIER  (H.  E.)  Florentine  History,  from  the  earliest  authentic  records 
to  the  Accession  of  Ferdinand  the  Third.  6 vols.  8vo.  London  1846. 

NEWPORT  (George.)  On  the  Anatomy  and  affinities  of  Pteronarcys  regalis, 
Newm. ; with  a Postscript,  containing  descriptions  of  some  American  Per- 
lidm,  together  with  Notes  on  their  Habits.  4to. 

On  the  Natural  History,  Anatomy  and  Development 

of  the  Oil  Beetle,  Meloe,  more  especially  of  Meloe  cicatricosus.  4to. 

NEWTON  (Sir  Isaac.)  Thirteen  Letters  from  Sir  Isaac  Newton  to  John 
Covel,  D.D.,  from  original  Manuscripts  in  the  Library  of  Dawson  Turner, 
Esq.,  F.R.S.  8vo.  Norwich  1848. 

OERSTED  (H.  C.)  Precis  d’une  Serie  d’Experiences  sur  le  Diamagnetisme. 

OWEN  (R.)  On  Parthenogenesis.  8vo.  London. 

On  the  Nature  of  Limbs.  8vo.  London  1849. 

PASSOT  (F.)  Refutation  de  la  Solution  Synthetique  donnee  par  Newton  du 
probleme  des  Forces  centrales.  Sheet.  Paris  1849. 

PEIRCE  (Benjamin.)  The  Latitude  of  the  Cambridge  Observatory,  in  Mas- 
sachusetts, determined  by  W.  C.  Bond  and  others. 

PELL  ATT  (Apsley.)  Curiosities  of  Glass  Making,  &c.  4to.  London  1849. 

PERIGAL  (Henry.)  Transformations  of  a Kinematic  Curve.  A Sheet. 

PETTENKOFER  (D.  M.)  Die  Chemie  in  ihrem  Verhaltnisse  zur  Physiolo- 
gic und  Pathologic.  Festrede.  4to.  Milnchen  1848. 

PICKETT  (W.  V.)  The  Fine  Arts  Journal,  containing  the  Exposition  of  a 
New  System  of  Architecture.  4to.  London  1847. 

New  Forms  in  Architecture  for  Iron.  8vo.  London  1849. 

PILBROW  (James.)  A New  Method  of  Traction  for  Railways  and  Canals, 
called  the  Hydrodynamic  System  of  Propulsion.  8vo.  London  1848. 


Donors. 

The  Admiralty. 

Depot  de  la  Marine. 

M.  Beat  de  Berber. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

Lady  Davy. 

Hon.  East  India  Company. 

Prof.  Boguslawski. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 


D.  Turner,  Esq.,  F.R.S. 


The  Author. 
The  Author. 


The  Author. 

Major  Graham. 

The  Author. 

The  Author. 

The  Bavarian  Academy. 

The  Author. 


The  Author. 


[ 13  ] 


Presents. 

PLANA  (Jean.)  Recherches  AnaRtiques  sur  la  Decouverte  de  la  Loi  de  la 
Pesanteur  des  Planetes  vers  le  Soleil,  et  sur  la  Theorie  de  leur  mouvement 
elliptique.  4to.  Turin  1848. 

PORTRAITS 

Portrait  of  J.  J.  Selby,  Esq. 

Dr.  John  Lee,  F.R.S. 

William  Yarrell,  Esq. 

John  Gould,  Esq.,  F.R.S. 

J.  S.  Henslow,  Esq. 

N.  Wallich,  Esq.,  F.R.S. 

Sir  William  Jardine. 

Bishop  of  Norwich,  F.R.S.  (^Lithograph  by  T.  H.  Maguire.) 

Lieut.  Holman,  F.R.S.,  by  J.  R.  Jackson,  from  the  Picture  by 
J.  P.  Knight,  R.A.  Mezzotint. 

W.  R.  Grove,  Esq.,  from  a Daguerreotype  by  Mr.  Claudet. 

The  Marquis  of  Northampton,  P.R.S.,  by  the  late  Thomas  Phillips, 
Esq.,  R.A. 

Sir  Charles  Lyell,  F.R.S.,  lithography  from  a Daguerreotype  by 
J.  E.  Mayall. 

M.  Faraday,  Esq.,  F.R.S.,  from  a Daguerreotype  by  Mr.  Claudet. 
Lithograph. 

QUARANTA  (Bernardo.)  Illustrazione  di  una  Ostagra  dissotterrata  in  Pom- 
pei  e falsamente  chiamata  Forcipe  Ercolanese.  8vo. 

QUETELET  (A.)  Notice  sur  Le  Colonel  G.  P.  Dandelin.  8vo.  Bruxelles  1 848. 

Du  Systeme  Social  et  des  Lois  qui  le  r%issent.  8vo. 

Paris  1848. 

Observations  des  Phenomenes  Periodiques.  4to.  Brux- 
elles 1848. 

Sur  le  Climat  de  la  Belgique.  4to.  Bruxelles  1848. 

REGNAULT  (V.)  Cours  Elementaire  de  Chimie.  4to.  Paris  1848. 

ROGERS  (H.  D.)  An  Address  on  the  recent  progress  of  Geological  Research 
in  the  United  States,  delivered  at  the  Fifth  Annual  Meeting  of  the  Asso- 
ciation of  American  Geologists  and  Naturalists,  held  at  Washington  in 
May  1844.  8vo.  Philadelphia  1844. 

ROGERS  (W.  B.)  and  ROGERS  (R.  E.)  On  the  Absorption  of  Carbonic 
Acid  Gas  by  Liquids.  8vo.  Newhaven  1848. 

ROGERS  (H.  D.)  and  ROGERS  (W.  B.)  An  Account  of  Two  Remarkable 
Trains  of  Erratic  Blocks  in  Berkshire,  Massachusetts. 

ROSS  (Sir  John.)  A Short  Treatise  on  the  Deviation  of  the  Mariner’s  Com- 
pass. 8vo.  London  1849. 

ROTHMAN  (R.  W.)  Observations  on  the  Climate  of  Italy  and  other  Coun- 
tries in  Ancient  Times.  8vo.  London  1848. 

SAINT  GERMAIN  (Bertrand  de.)  Des  Manifestations  de  la  Vie  et  de  ITntel- 
ligence  a I’aide  de  I’Organisation.  8vo.  Paris  1848. 

SCHNEIDER  (W.  G.)  Ueber  das  Meteoreisen  von  Seelasgen  bei  Schwiebus. 

SCHUMACHER  (C.  H.)  Astronomische  Nachrichten.  Nos.  628  to  665.  4to. 

SHADWELL  (C.  F.)  Tables  for  determining  the  Latitude  by  the  Simulta- 
neous Altitudes  of  two  Stars.  8vo.  London  1849. 


Donors. 
The  Author. 


Mr.  George  Ransome. 


Lieut.  Holman,  F.R.S. 

Mr.  Claudet. 

The  Marquis  of  Northamp- 
ton. 

Mr.  J.  E.  Mayall. 

Mr.  Claudet. 

The  Author. 

The  Author. 


M.  Biot. 

The  Author. 


The  Authors. 

The  Authors. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 
The  Author. 
The  Author. 


[ 14  ] 


Presents. 

SIBSON  (Francis.)  Illustrations  of  Diseases  of  the  Chest.  8vo.  Worcester  1844. 

On  the  Movements  of  Respiration  in  Disease,  and  on  the 

use  of  a Chest-Measurer.  8vo.  1848. 

SIMPSON  (J.  Y.)  Obstetrical  Statistics,  &c. ; a second  letter  in  reply  to 
Dr.  Collins.  8vo.  Edinburgh  1848. 

SMEE  (Alfred.)  Elements  of  Electro-Biology.  8vo.  London  1849. 

SMYTH  (Capt.  W.  H.)  Description  of  an  Astrological  Clock  belonging  to 
the  Society  of  Antiquaries.  4to. 

SMYTH  (C.  P.)  On  the  Determination  of  the  True  Strength  and  Direction  of 
the  Wind  at  Sea.  4to.  Edinburgh  1848. 

Notice  of  the  Orbit  of  the  Binary  Star  a Centauri,  as  recently 

determined  by  Captain  Jacob.  4to.  Edinburgh  1848. 

SOLLY  (E.)  Syllabus  of  a Complete  Course  of  Lectures  on  Chemistry.  8vo. 
London  1849. 

SOMERVILLE  (Mary.)  Physical  Geography.  2 vols.  8vo.  London  1848. 

SPENCE  (William.)  Address  delivered  at  the  Anniversary  Meeting  of  the  En- 
tomological Society  of  London  on  the  22nd  Jan.  1849.  8vo.  London  1849. 

STANFORD  (J.  F.)  Systematic  Colonization;  a Series  of  Letters.  8vo.  Lon- 
don 1848. 

STRATFORD  (Lieut.)  The  Nautical  Almanac  for  the  year  1852.  8vo.  Lon- 
don 1848. 

SYKES  (Lieut.-Col.)  A Notice  respecting  some  Fossils  collected  in  Cutch, 
by  Captain  Walter  Smee. 

. — Mortality  in  the  Jails  of  the  twenty-four  Pergunnahs, 

Calcutta. 

Notes  on  the  Religious,  Moral,  and  Political  State  of 

India  before  the  Mahomedan  Invasion. 

On  the  Population  and  Mortality  of  Calcutta. 

Report  of  a Committee  of  the  Council  of  the  Statistical 

Society  of  London  to  investigate  the  State  of  the  Inhabitants  and  their 
Dwellings  in  Church  Lane,  St.  Giles’s. 

Statistics  of  Civil  Justice  in  Bengal. 

TAYLOR  (T.  G.)  Meteorological  Observations  made  at  the  Meteorological 
Bungalow  on  Dodabetta,  8640  feet  above  the  level  of  the  sea,  in  1847-48. 
4to.  3Iadras  1848. 

Astronomical  Observations  made  at  the  Observatory  at 

Madras  in  1843-47.  4to.  Madras  1848. 

Meteorological  Observations  made  at  the  Observatory  at 

Madras  in  1841-45.  4to.  Madras. 

TEMMINCK  (C.  J.)  Coup-d’ceil  general  sur  les  Possessions  Neerlandaises 
dans  rinde  Archipelagique. 

TURNER  (Dawson.)  Guide  to  the  Historian,  the  Biographer,  the  Antiquary, 
the  Man  of  Literary  Curiosity  and  the  Collector  of  Autographs,  towards 
the  Verification  of  Manuscripts  by  reference  to  Engraved  Fac-similes  of 
Handwriting.  8vo.  Yarmouth  1848. 

VERLANDER  (H.)  The  Vestal,  and  other  Poems.  8vo.  London  1837. 

WALDHEIM  (G.  F.  de.)  Notice  sur  quelques  Sauriens  Fossiles  du  Gou- 
vernement  de  Moscou. 


Donors. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Author. 

The  Authoress. 

The  Author. 

The  Author. 

Lieut.  Stratford,  F.R.S. 

The  Author. 


The  Directors  of  the  Hon. 
East  India  Company. 


J.  E.  Gray,  Esq.,  F.R.S, 
The  Author. 


The  Author. 
The  Author. 


[ 15  ] 


Presents. 

WALTERSHAUSEN  (Sartorius  v.)  Physisch-geographische  Skizze  von 
Island.  8vo.  Gottingen  1847. 

WARREN  (J.  C.)  Effects  of  Chloroform  and  of  Strong  Chloric  Ether,  as 
Narcotic  Agents.  8vo.  Boston,  U.S.  1849. 

The  Physiological  Effects  of  Alcoholic  Drinks,  with  Docu- 
ments and  Records  of  the  Massachusetts  Temperance  Society.  8vo.  Boston, 
U.S.  1848. 

WARTMANN  (E.)  Sur  divers  Phenomenes  Meteorologiques. 

Troisieme,  Cinquieme,  Sixieme  et  Septieme  Memoires  sur 

ITnduction.  8vo. 

WELD  (C.  R.)  The  Eleventh  Chapter  of  the  History  of  the  Royal  Society, 
with  a review  of  the  same  by  Professor  De  Morgan,  reprinted  by  Charles 
Babbage,  Esq.,  F.R.S.  8vo.  London  1848. 

WHICHCORD  (J.)  Observations  on  the  Sanitary  Condition  of  Maidstone. 
8 VO.  London  1849. 

WILLIAMS  (George.)  Historical  and  Descriptive  Memoir  on  the  Towm  and 
Environs  of  Jerusalem.  8vo.  London  1849. 

WILLICH  (C.  M.)  Annual  Supplement  to  the  Tithe  Commutation  Tables. 
8vo.  London  1849. 

WILLIS  (Rev.  Robert.)  The  Architectural  History  of  the  Holy  Sepulchre 
at  Jerusalem.  8vo.  London  1849. 

WINDUS  (Thomas.)  A New  Elucidation  of  the  Subjects  on  the  celebrated 
Portland  Vase.  fol.  London  1845. 

WEDGWOOD  (J.)  Reprint  of  a description  of  the  Portland  Vase,  by 
J.  Wedgwood,  F.R.S.,  with  the  addition  of  notes  by  Thomas  Windus,  F.S.A. 
fol.  London  1845. 


Donors. 
The  Author. 

The  Author. 


The  Author. 

C.  Babbage,  Esq.,  F.R.S. 

The  Author. 

The  Rev.  Robert  Willis. 
The  Author. 

The  Author. 

The  Author. 

Thomas  Windus,  Esq. 


r.v 


M ■ 

L 


i* 


kf^- 


.•=^.■^r^■^  ■ l i’  P'.v''  ■ 

■ -'  J ■ *:  ' V ■'■■  •'  .t>tu:‘l  i'  ' - ^ 

/■:t''s.;  " ■••i!”.'  bh'ildO  ■^iy‘T'i::'idyf:hittv)-%  ■'  ■t'ifl  ' (.!>" •C')  >133 U.'  •''  ' ■' 

;::.  ■ fWt^ I ' •:  .0.  .■'^*;  J-' ,•■  Jt .) ' J^  t .'•■ti'<  i!><>.')fA 'T,i'>  f^iT'^'U.^J.  f""? i ji<)fc </■  V'i't' I . — — » I- .i 

■ \t  i . • . ♦ 

: ;hb;:;'j:t4tC0u;  ' ;■  ,.,;)Jvf'<«jl  w’.' '.fr  . " 

■ ',.n:,;i>,:;  „ ■ ^:  ).Ki' ;3u1i{ AW 

■ - ■■v’'''r  :_:i.  , . ..  ■•■'  'V  ■ ,, 


'V‘  • - ‘'-’ttiWvi 


.i>- 


- ^.. 


':  ' ■!-','-:{?^r'.'  rJj-;.  . ! Xd  Wni'  //  ' 

,7;f  ,-t  .■)f!  •.^)ok^rt'F'r'  '-  • ..■/ii^'j^;:  ',r;fej.>-J  fl  if>W‘  ■ 

.'■■  ■■  ‘‘ >'f,,:/, 4 ■■  ' / ' ’ ’'li 

•;  i-  ■ ■■-  "--'X^^-^  ‘ 

..;>;i!i ,Vj'o;'o,U  .v^H' rtd'i*.  ■ ••■^:.;■K■>’' ^^■•^^^  : IN.  ■ ••  ‘i  t.'^'^>) '’’‘''^AJJvii'iV""'^ 

V.  - i;^'  '■  :- . ■;  , ■ ’ .-  : *.^;’-'U  "{•>  i-fT^i^rTCr  ' : 

<A  I ;'.■;}'  i'.tr,jt;iitii;r(}X  / •)«,,!;'  \ 0:  i/.i.'  ' * (.M'.*'))  ii  /f3..MV 

■;,■  , i ■■  , ■*  ■ .•,'■  ’ ■'  I';  , ■ ■:  .-• 

. V*  f’.'.-'i'W  ■’  •■•■>6'-'.»-'’-.)V‘«t’^i  1i' 


;4r 


r A- 


-t  'f  f'  ':  pi'^JyNn.iUii 


i./i'i'’ 


, "it, 


:;^VV 


.1(1 


!!;;(**  ijr  lV<..lr.-,'f.iT'.  '?  ^>V^^  .n:'v  a^''i«fjjcl  -nU  1">  •ft-.-f'-'.'l‘'it>;rt.l:yWi^,.^j~  < >.-  ,m,.  ^ iX-  ;'l>'l 

I'l'  .' I» k'/-’ 


iV'/' Jjijpv: '^’4',,  . VV  (* -^‘!?-p3.vF  (^^)«• 

►A.5?.,3  -'d  vjtnri '.'ti  iiiuSil'jPyil;  itlu'if  ;4:'r''3',}iOo:.^'l''*V.' 


•■  ■ { 

■ '3  ■ . 


. ‘ ' ’ ' .“  '“■’  ''  f/  ■'•*•*' 

* ‘ -"Vi,  ■ '•, 


'X 

X'X'/  '• 


■ Ai  .'.V;4.;i'  ;. 


,.yy,  • 


Xim- 


■V  ■ 


Vl' 


' vN  ••  •••  ■ -4  • 

':-i  ■-  ■ ■ 

.-V 


Safe 

•■  s; 


A y 


■ •.  7i^'  IrVTit:.  _ 

-T  ~:  -’ ' a’  , ' -RbS;,  '■.*  -, 


A 


:\:ai